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Can you take Doxepin with Thioridazine?

1 drug interaction and 72 additional warnings found for the following 2 drugs:

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Drug interactions

Major drug interactions

Major:

doxepin thioridazine

Applies to: doxepin and thioridazine

Using doxepin together with thioridazine is not recommended. This can increase the effects of either medication.

Call your doctor if you have side effects such as:

  • extreme drowsiness
  • confusion
  • agitation
  • vomiting
  • blurred vision
  • feeling hot or cold
  • sweating
  • muscle stiffness
  • fainting
  • seizure (convulsions)
  • coma

Using these medications together can also cause:

  • uncontrollable movements of the mouth, tongue, cheeks, jaw, arms, or legs
  • fever
  • muscle rigidity
  • irregular pulse
  • fast or irregular heartbeats

If your doctor prescribes these medications together, you may need a dose adjustment or special tests to safely take both medications.

It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Food/lifestyle interactions

Moderate food/lifestyle interactions

Moderate:

doxepin Alcohol (Ethanol)

Applies to: doxepin

Ask your doctor before using doxepin together with ethanol (alcohol), this can alter the effects of doxepin and cause increased side effects.

Call the doctor if you experience:

  • uneven heartbeats
  • extreme drowsiness
  • confusion
  • agitation
  • vomiting
  • blurred vision
  • sweating
  • muscle stiffness
  • feeling light-headed
  • seizures

You should be warned not to exceed recommended dosages, to avoid alcohol, and to avoid activities requiring mental alertness.

If your doctor prescribes these medications together, you may need a dose adjustment to safely take this combination.

It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Moderate:

thioridazine Alcohol (Ethanol)

Applies to: thioridazine

Ask your doctor before using thioridazine together with ethanol (alcohol).

This can cause:

  • uncontrollable movements
  • agitation
  • seizures
  • severe dizziness or fainting
  • coma
  • very deep sleep
  • irregular heartbeats
  • high or low body temperature

Use caution when driving, operating machinery, or performing other hazardous activities, these medicaions may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities.

It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Disease interactions

70 potential interactions Applies to: 41 conditions, including High Blood Pressure, Depression, Bipolar Disorder, Heart Attack, and Seizures.

Abnormal Electrocardiogram

Major:

thioridazine

Thioridazine has a major potential interaction with Abnormal Electrocardiogram.

The use of thioridazine is contraindicated in patients with congenital or acquired QT interval prolongation syndromes or a history of cardiac arrhythmias. Thioridazine can prolong the QT interval of the electrocardiogram in a dose-related manner. The risk of torsade de pointes is progressively increased as the degree of prolongation becomes greater. In a crossover study of nine patients, a single 50 mg dose of thioridazine increased the QTc interval by a mean maximum of 23 msec compared to placebo. During postmarketing experience, torsade de pointes and sudden death have been reported, although a causal relationship has not been determined. The manufacturer states that thioridazine should not be administered in patients with a baseline QTc interval greater than 450 msec, and that it should be discontinued in patients with QTc measurements exceeding 500 msec during therapy. Electrolyte disturbances such as hypokalemia and hypomagnesemia may augment the prolongation effect of thioridazine on the QT interval and should be corrected prior to institution of therapy. Patients who experience frequent, severe, or prolonged diarrhea may be subject to electrolyte losses and should be followed closely and managed accordingly during therapy with thioridazine.

Acute Alcohol Intoxication

Major:

thioridazine

Thioridazine has a major potential interaction with Acute Alcohol Intoxication.

Phenothiazines are contraindicated in the presence of large amounts of central nervous system depressants such as alcohol. The risk of suicide and the danger of overdose may be increased in patients who use alcohol excessively. Phenothiazines should be used with caution in patients experiencing alcohol withdrawal.

Alcoholism

Major:

doxepin

Doxepin has a major potential interaction with Alcoholism.

Tricyclic antidepressants (TCAs), can lower the seizure threshold and trigger seizures. These drugs should be used with extreme caution in patients with a history of seizures, or other predisposing factors, such as head trauma, CNS abnormalities, and alcoholism. Daily dose restrictions might apply for specific antidepressants. Physicians are encouraged to get additional dosing recommendations on the manufacturer's prescribing information.

Major:

thioridazine

Thioridazine has a major potential interaction with Alcoholism.

Phenothiazines are contraindicated in the presence of large amounts of central nervous system depressants such as alcohol. The risk of suicide and the danger of overdose may be increased in patients who use alcohol excessively. Phenothiazines should be used with caution in patients experiencing alcohol withdrawal.

Moderate:

doxepin

Doxepin has a moderate potential interaction with Alcoholism.

Tricyclic antidepressants can enhance the response to alcohol. In patients who may use alcohol excessively, it should be borne in mind that the potentiation may increase the danger inherent in any suicide attempt or overdosage.

Altered Consciousness

Major:

thioridazine

Thioridazine has a major potential interaction with Altered Consciousness.

The use of phenothiazines is contraindicated in comatose patients and patients with severe central nervous system depression. Phenothiazines may potentiate the CNS and respiratory depression in these patients.

Arrhythmia

Major:

doxepin

Doxepin has a major potential interaction with Arrhythmia.

Tricyclic and tetracyclic antidepressants (TCAs) may cause orthostatic hypotension, reflex tachycardia, syncope, and dizziness, particularly during initiation of therapy or rapid escalation of dosage. Imipramine appears to have the greatest propensity to induce these effects, while secondary amines such as nortriptyline may do so less frequently. Tolerance to the hypotensive effects often develops after a few doses to a few weeks. Rarely, collapse and sudden death have occurred secondary to severe hypotension. Other reported adverse cardiovascular effects include tachycardia, arrhythmias, heart block, hypertension, thrombosis, thrombophlebitis, myocardial infarction, strokes, congestive heart failure, and ECG abnormalities such as PR and QT interval prolongation. Therapy with TCAs should be avoided during the acute recovery phase following myocardial infarction, and should be administered only with extreme caution in patients with hyperthyroidism, a history of cardiovascular or cerebrovascular disease, or a predisposition to hypotension. Close monitoring of cardiovascular status, including ECG changes, is recommended at all dosages. Many of the newer antidepressants, including bupropion and the selective serotonin reuptake inhibitors (SSRIs), are considerably less or minimally cardiotoxic and may be appropriate alternatives.

Major:

thioridazine

Thioridazine has a major potential interaction with Arrhythmia.

The use of thioridazine is contraindicated in patients with congenital or acquired QT interval prolongation syndromes or a history of cardiac arrhythmias. Thioridazine can prolong the QT interval of the electrocardiogram in a dose-related manner. The risk of torsade de pointes is progressively increased as the degree of prolongation becomes greater. In a crossover study of nine patients, a single 50 mg dose of thioridazine increased the QTc interval by a mean maximum of 23 msec compared to placebo. During postmarketing experience, torsade de pointes and sudden death have been reported, although a causal relationship has not been determined. The manufacturer states that thioridazine should not be administered in patients with a baseline QTc interval greater than 450 msec, and that it should be discontinued in patients with QTc measurements exceeding 500 msec during therapy. Electrolyte disturbances such as hypokalemia and hypomagnesemia may augment the prolongation effect of thioridazine on the QT interval and should be corrected prior to institution of therapy. Patients who experience frequent, severe, or prolonged diarrhea may be subject to electrolyte losses and should be followed closely and managed accordingly during therapy with thioridazine.

Major:

thioridazine

Thioridazine has a major potential interaction with Arrhythmia.

Phenothiazines may cause hypotension. Patients with pheochromocytoma, cerebral vascular or renal insufficiency, cardiovascular disease, or a severe cardiac reserve deficiency (e.g., mitral insufficiency) may be more prone to hypotensive reactions. Close monitoring is recommended during treatment if used in at-risk patients; some products may be contraindicated (e.g., thioridazine). Large doses and parenteral administration should be used cautiously, or avoided, in patients with impaired cardiovascular systems.

Bipolar Disorder

Moderate:

doxepin

Doxepin has a moderate potential interaction with Bipolar Disorder.

A major depressive episode can be the initial presentation of bipolar disorder. Patients with depressive symptoms should be adequately screened to determine if they are at risk for bipolar disorder prior to initiating treatment with doxepin. This screening should include a detailed psychiatric history, including a family history of suicide, bipolar disorder, and depression. It should be noted that doxepin is not approved for use in treating bipolar depression.

Moderate:

doxepin

Doxepin has a moderate potential interaction with Bipolar Disorder.

Tricyclic antidepressants (TCAs) may aggravate symptoms of psychosis in schizophrenic patients, particularly those with paranoid symptomatology. Depressed patients, usually those with bipolar disorder, may experience a switch from depression to mania or hypomania. These occurrences have also been reported rarely with the tetracyclic antidepressant, maprotiline. Therapy with these agents should be administered cautiously in patients with schizophrenia, bipolar disorder, or a history of mania.

Moderate:

doxepin

Doxepin has a moderate potential interaction with Bipolar Disorder.

A major depressive episode can be the initial presentation of bipolar disorder. Patients with depressive symptoms should be adequately screened to determine if they are at risk for bipolar disorder prior to initiating treatment with a tricyclic antidepressant. This screening should include a detailed psychiatric history, including a family history of suicide, bipolar disorder, and depression. It should be noted that tricyclic antidepressants are not approved for use in treating bipolar depression.

Bone Marrow Depression/Low Blood Counts

Major:

thioridazine

Thioridazine has a major potential interaction with Bone Marrow Depression/Low Blood Counts.

Phenothiazines may cause hematologic toxicity. In patients with preexisting blood dyscrasias, bone marrow suppression, or a history of drug-induced leukopenia or neutropenia, phenothiazines should not be used or are contraindicated. Complete blood counts should be regularly monitored in patients with risk factors for blood dyscrasias. If white blood cell counts indicate cellular depression, discontinue treatment and institute appropriate therapy.

Moderate:

doxepin

Doxepin has a moderate potential interaction with Bone Marrow Depression/Low Blood Counts.

The use of tricyclic and tetracyclic antidepressants (TCAs) has rarely been associated with bone marrow suppression. Leukopenia, agranulocytosis, thrombocytopenia, anemia, eosinophilia, purpura, and pancytopenia have been reported with some TCAs. Patients with preexisting bone marrow suppression or blood dyscrasias receiving TCAs should be monitored closely during therapy for further decreases in blood counts.

Breast Cancer

Moderate:

thioridazine

Thioridazine has a moderate potential interaction with Breast Cancer.

The chronic use of phenothiazines is associated with persistent elevations in prolactin levels. The clinical significance in patients with a history of breast cancer is unknown and should be considered prior to therapy; approximately one-third of human breast cancers are thought to be prolactin-dependent. Chronic administration of neuroleptic drugs has been associated with mammary tumorigenesis in animal studies; however, evidence is inconclusive in humans.

Cardiovascular Conditions and Disorders

Major:

doxepin

Doxepin has a major potential interaction with Cardiovascular Conditions and Disorders.

Tricyclic and tetracyclic antidepressants (TCAs) may cause orthostatic hypotension, reflex tachycardia, syncope, and dizziness, particularly during initiation of therapy or rapid escalation of dosage. Imipramine appears to have the greatest propensity to induce these effects, while secondary amines such as nortriptyline may do so less frequently. Tolerance to the hypotensive effects often develops after a few doses to a few weeks. Rarely, collapse and sudden death have occurred secondary to severe hypotension. Other reported adverse cardiovascular effects include tachycardia, arrhythmias, heart block, hypertension, thrombosis, thrombophlebitis, myocardial infarction, strokes, congestive heart failure, and ECG abnormalities such as PR and QT interval prolongation. Therapy with TCAs should be avoided during the acute recovery phase following myocardial infarction, and should be administered only with extreme caution in patients with hyperthyroidism, a history of cardiovascular or cerebrovascular disease, or a predisposition to hypotension. Close monitoring of cardiovascular status, including ECG changes, is recommended at all dosages. Many of the newer antidepressants, including bupropion and the selective serotonin reuptake inhibitors (SSRIs), are considerably less or minimally cardiotoxic and may be appropriate alternatives.

Major:

doxepin

Doxepin has a major potential interaction with Cardiovascular Conditions and Disorders.

Tricyclic antidepressants should be used with extreme caution in patients with evidence of cardiovascular disease because of the possibility of fluctuations in the blood pressure, arrhythmias, conduction defects, tachycardia, myocardial infarction and stroke. This also applies to patients who have family history of sudden death, cardiac dysrhythmias, or conduction disturbances. In some cases a gradual dose titration is recommended.

Major:

thioridazine

Thioridazine has a major potential interaction with Cardiovascular Conditions and Disorders.

Phenothiazines may cause hypotension. Patients with pheochromocytoma, cerebral vascular or renal insufficiency, cardiovascular disease, or a severe cardiac reserve deficiency (e.g., mitral insufficiency) may be more prone to hypotensive reactions. Close monitoring is recommended during treatment if used in at-risk patients; some products may be contraindicated (e.g., thioridazine). Large doses and parenteral administration should be used cautiously, or avoided, in patients with impaired cardiovascular systems.

Central Nervous System Disorders

Major:

doxepin

Doxepin has a major potential interaction with Central Nervous System Disorders.

Tricyclic antidepressants (TCAs), can lower the seizure threshold and trigger seizures. These drugs should be used with extreme caution in patients with a history of seizures, or other predisposing factors, such as head trauma, CNS abnormalities, and alcoholism. Daily dose restrictions might apply for specific antidepressants. Physicians are encouraged to get additional dosing recommendations on the manufacturer's prescribing information.

Moderate:

thioridazine

Thioridazine has a moderate potential interaction with Central Nervous System Disorders.

Phenothiazines can lower the seizure threshold. Caution is recommended during administration in patients with a history of convulsive disorders or EEG abnormalities. Anticonvulsant therapy should be maintained or adequately adjusted during phenothiazine treatment.

Cerebrovascular Insufficiency

Major:

doxepin

Doxepin has a major potential interaction with Cerebrovascular Insufficiency.

Tricyclic and tetracyclic antidepressants (TCAs) may cause orthostatic hypotension, reflex tachycardia, syncope, and dizziness, particularly during initiation of therapy or rapid escalation of dosage. Imipramine appears to have the greatest propensity to induce these effects, while secondary amines such as nortriptyline may do so less frequently. Tolerance to the hypotensive effects often develops after a few doses to a few weeks. Rarely, collapse and sudden death have occurred secondary to severe hypotension. Other reported adverse cardiovascular effects include tachycardia, arrhythmias, heart block, hypertension, thrombosis, thrombophlebitis, myocardial infarction, strokes, congestive heart failure, and ECG abnormalities such as PR and QT interval prolongation. Therapy with TCAs should be avoided during the acute recovery phase following myocardial infarction, and should be administered only with extreme caution in patients with hyperthyroidism, a history of cardiovascular or cerebrovascular disease, or a predisposition to hypotension. Close monitoring of cardiovascular status, including ECG changes, is recommended at all dosages. Many of the newer antidepressants, including bupropion and the selective serotonin reuptake inhibitors (SSRIs), are considerably less or minimally cardiotoxic and may be appropriate alternatives.

Major:

thioridazine

Thioridazine has a major potential interaction with Cerebrovascular Insufficiency.

Phenothiazines may cause hypotension. Patients with pheochromocytoma, cerebral vascular or renal insufficiency, cardiovascular disease, or a severe cardiac reserve deficiency (e.g., mitral insufficiency) may be more prone to hypotensive reactions. Close monitoring is recommended during treatment if used in at-risk patients; some products may be contraindicated (e.g., thioridazine). Large doses and parenteral administration should be used cautiously, or avoided, in patients with impaired cardiovascular systems.

Dehydration

Major:

doxepin

Doxepin has a major potential interaction with Dehydration.

Tricyclic and tetracyclic antidepressants (TCAs) may cause orthostatic hypotension, reflex tachycardia, syncope, and dizziness, particularly during initiation of therapy or rapid escalation of dosage. Imipramine appears to have the greatest propensity to induce these effects, while secondary amines such as nortriptyline may do so less frequently. Tolerance to the hypotensive effects often develops after a few doses to a few weeks. Rarely, collapse and sudden death have occurred secondary to severe hypotension. Other reported adverse cardiovascular effects include tachycardia, arrhythmias, heart block, hypertension, thrombosis, thrombophlebitis, myocardial infarction, strokes, congestive heart failure, and ECG abnormalities such as PR and QT interval prolongation. Therapy with TCAs should be avoided during the acute recovery phase following myocardial infarction, and should be administered only with extreme caution in patients with hyperthyroidism, a history of cardiovascular or cerebrovascular disease, or a predisposition to hypotension. Close monitoring of cardiovascular status, including ECG changes, is recommended at all dosages. Many of the newer antidepressants, including bupropion and the selective serotonin reuptake inhibitors (SSRIs), are considerably less or minimally cardiotoxic and may be appropriate alternatives.

Dementia

Major:

thioridazine

Thioridazine has a major potential interaction with Dementia.

Antipsychotic drugs are not approved for the treatment of patients with dementia-related psychosis. Older patients with dementia-related psychosis treated with antipsychotic drugs are at an increased risk of death; although the causes were varied, most of the deaths appeared to be either cardiovascular (e.g., heart failure, sudden death) or infectious (e.g., pneumonia) in nature. A causal relationship with antipsychotic use has not been established. In controlled trials in older patients with dementia-related psychosis, patients randomized to risperidone, aripiprazole, and olanzapine had higher incidence of cerebrovascular adverse events (e.g., stroke, transient ischemic attack), including fatalities, compared to patients treated with placebo.

Depression

Major:

doxepin

Doxepin has a major potential interaction with Depression.

A variety of abnormal thinking and behavior changes have been reported to occur in association with the use of most anxiolytics, sedatives and hypnotics. Some of these changes include decreased inhibition, aggressiveness, agitation, and hallucinations. These drugs can cause or exacerbate mental depression and cause suicidal behavior and ideation. Therapy with these drugs should be administered cautiously in patients with a history of depression or other psychiatric disorders. Patients should be monitored for any changes in mood or behavior. It may be prudent to refrain from dispensing large quantities of medication to these patients.

Diabetes Mellitus

Moderate:

doxepin

Doxepin has a moderate potential interaction with Diabetes Mellitus.

There have been reports of both elevation and lowering of blood sugar levels in patients receiving tricyclic antidepressants. These drugs should be used with caution in patients with hypoglycemia, hyperglycemia or diabetes. Monitoring sugar levels is recommended.

Moderate:

doxepin

Doxepin has a moderate potential interaction with Diabetes Mellitus.

Both elevation and lowering of blood sugar levels have been reported with the use of some tricyclic antidepressants (TCAs). Rarely, these effects have also occurred with maprotiline, a tetracyclic antidepressant. Patients with diabetes should be monitored for worsening control of blood glucose when treated with these agents, particularly during dosage escalation or whenever dosage has been altered.

Diarrhea

Major:

thioridazine

Thioridazine has a major potential interaction with Diarrhea.

The use of thioridazine is contraindicated in patients with congenital or acquired QT interval prolongation syndromes or a history of cardiac arrhythmias. Thioridazine can prolong the QT interval of the electrocardiogram in a dose-related manner. The risk of torsade de pointes is progressively increased as the degree of prolongation becomes greater. In a crossover study of nine patients, a single 50 mg dose of thioridazine increased the QTc interval by a mean maximum of 23 msec compared to placebo. During postmarketing experience, torsade de pointes and sudden death have been reported, although a causal relationship has not been determined. The manufacturer states that thioridazine should not be administered in patients with a baseline QTc interval greater than 450 msec, and that it should be discontinued in patients with QTc measurements exceeding 500 msec during therapy. Electrolyte disturbances such as hypokalemia and hypomagnesemia may augment the prolongation effect of thioridazine on the QT interval and should be corrected prior to institution of therapy. Patients who experience frequent, severe, or prolonged diarrhea may be subject to electrolyte losses and should be followed closely and managed accordingly during therapy with thioridazine.

Electrolyte Abnormalities

Major:

thioridazine

Thioridazine has a major potential interaction with Electrolyte Abnormalities.

The use of thioridazine is contraindicated in patients with congenital or acquired QT interval prolongation syndromes or a history of cardiac arrhythmias. Thioridazine can prolong the QT interval of the electrocardiogram in a dose-related manner. The risk of torsade de pointes is progressively increased as the degree of prolongation becomes greater. In a crossover study of nine patients, a single 50 mg dose of thioridazine increased the QTc interval by a mean maximum of 23 msec compared to placebo. During postmarketing experience, torsade de pointes and sudden death have been reported, although a causal relationship has not been determined. The manufacturer states that thioridazine should not be administered in patients with a baseline QTc interval greater than 450 msec, and that it should be discontinued in patients with QTc measurements exceeding 500 msec during therapy. Electrolyte disturbances such as hypokalemia and hypomagnesemia may augment the prolongation effect of thioridazine on the QT interval and should be corrected prior to institution of therapy. Patients who experience frequent, severe, or prolonged diarrhea may be subject to electrolyte losses and should be followed closely and managed accordingly during therapy with thioridazine.

Gastrointestinal Obstruction

Major:

doxepin

Doxepin has a major potential interaction with Gastrointestinal Obstruction.

Tricyclic and tetracyclic antidepressants (TCAs) have anticholinergic activity, to which elderly patients are particularly sensitive. Tertiary amines such as amitriptyline and trimipramine tend to exhibit greater anticholinergic effects than other agents in the class. Therapy with TCAs should be administered cautiously in patients with preexisting conditions that are likely to be exacerbated by anticholinergic activity, such as urinary retention or obstruction; angle-closure glaucoma, untreated intraocular hypertension, or uncontrolled primary open-angle glaucoma; and gastrointestinal obstructive disorders. In patients with angle-closure glaucoma, even average doses can precipitate an attack. Glaucoma should be treated and under control prior to initiation of therapy with TCAs, and intraocular pressure monitored during therapy.

Glaucoma, Narrow Angle

Moderate:

doxepin

Doxepin has a moderate potential interaction with Glaucoma, Narrow Angle.

Tricyclic antidepressants as other type of antidepressants have an effect on pupil size causing dilation. This effect can potentially narrow the eye angle resulting in increased intraocular pressure and angle closure glaucoma, especially in predisposed patients. These drugs should be used with caution in patients with anatomically narrow angle or history of glaucoma. Doxepin hydrochloride capsules are contraindicated in patients with glaucoma.

Glaucoma/Intraocular Hypertension

Major:

doxepin

Doxepin has a major potential interaction with Glaucoma/Intraocular Hypertension.

Tricyclic and tetracyclic antidepressants (TCAs) have anticholinergic activity, to which elderly patients are particularly sensitive. Tertiary amines such as amitriptyline and trimipramine tend to exhibit greater anticholinergic effects than other agents in the class. Therapy with TCAs should be administered cautiously in patients with preexisting conditions that are likely to be exacerbated by anticholinergic activity, such as urinary retention or obstruction; angle-closure glaucoma, untreated intraocular hypertension, or uncontrolled primary open-angle glaucoma; and gastrointestinal obstructive disorders. In patients with angle-closure glaucoma, even average doses can precipitate an attack. Glaucoma should be treated and under control prior to initiation of therapy with TCAs, and intraocular pressure monitored during therapy.

Major:

doxepin

Doxepin has a major potential interaction with Glaucoma/Intraocular Hypertension.

The use of doxepin is contraindicated in patients with glaucoma, or a tendency to urinary retention. These disorders should be ruled out before starting treatment, especially in elderly patients.

Moderate:

doxepin

Doxepin has a moderate potential interaction with Glaucoma/Intraocular Hypertension.

Some hypnotic drugs can have an anticholinergic effect and should be used with caution in patients with glaucoma, and trouble urinating due to retention or enlarged prostate.

Heart Attack

Major:

doxepin

Doxepin has a major potential interaction with Heart Attack.

The use of most tricyclic antidepressants is contraindicated in patients that are going through the acute recovery period after a myocardial infarction.

High Blood Pressure

Major:

thioridazine

Thioridazine has a major potential interaction with High Blood Pressure.

Phenothiazines may cause hypotension. Patients with pheochromocytoma, cerebral vascular or renal insufficiency, cardiovascular disease, or a severe cardiac reserve deficiency (e.g., mitral insufficiency) may be more prone to hypotensive reactions. Close monitoring is recommended during treatment if used in at-risk patients; some products may be contraindicated (e.g., thioridazine). Large doses and parenteral administration should be used cautiously, or avoided, in patients with impaired cardiovascular systems.

History - Cerebrovascular Disease

Major:

doxepin

Doxepin has a major potential interaction with History - Cerebrovascular Disease.

Tricyclic and tetracyclic antidepressants (TCAs) may cause orthostatic hypotension, reflex tachycardia, syncope, and dizziness, particularly during initiation of therapy or rapid escalation of dosage. Imipramine appears to have the greatest propensity to induce these effects, while secondary amines such as nortriptyline may do so less frequently. Tolerance to the hypotensive effects often develops after a few doses to a few weeks. Rarely, collapse and sudden death have occurred secondary to severe hypotension. Other reported adverse cardiovascular effects include tachycardia, arrhythmias, heart block, hypertension, thrombosis, thrombophlebitis, myocardial infarction, strokes, congestive heart failure, and ECG abnormalities such as PR and QT interval prolongation. Therapy with TCAs should be avoided during the acute recovery phase following myocardial infarction, and should be administered only with extreme caution in patients with hyperthyroidism, a history of cardiovascular or cerebrovascular disease, or a predisposition to hypotension. Close monitoring of cardiovascular status, including ECG changes, is recommended at all dosages. Many of the newer antidepressants, including bupropion and the selective serotonin reuptake inhibitors (SSRIs), are considerably less or minimally cardiotoxic and may be appropriate alternatives.

Major:

thioridazine

Thioridazine has a major potential interaction with History - Cerebrovascular Disease.

Phenothiazines may cause hypotension. Patients with pheochromocytoma, cerebral vascular or renal insufficiency, cardiovascular disease, or a severe cardiac reserve deficiency (e.g., mitral insufficiency) may be more prone to hypotensive reactions. Close monitoring is recommended during treatment if used in at-risk patients; some products may be contraindicated (e.g., thioridazine). Large doses and parenteral administration should be used cautiously, or avoided, in patients with impaired cardiovascular systems.

History - Myocardial Infarction

Major:

doxepin

Doxepin has a major potential interaction with History - Myocardial Infarction.

Tricyclic and tetracyclic antidepressants (TCAs) may cause orthostatic hypotension, reflex tachycardia, syncope, and dizziness, particularly during initiation of therapy or rapid escalation of dosage. Imipramine appears to have the greatest propensity to induce these effects, while secondary amines such as nortriptyline may do so less frequently. Tolerance to the hypotensive effects often develops after a few doses to a few weeks. Rarely, collapse and sudden death have occurred secondary to severe hypotension. Other reported adverse cardiovascular effects include tachycardia, arrhythmias, heart block, hypertension, thrombosis, thrombophlebitis, myocardial infarction, strokes, congestive heart failure, and ECG abnormalities such as PR and QT interval prolongation. Therapy with TCAs should be avoided during the acute recovery phase following myocardial infarction, and should be administered only with extreme caution in patients with hyperthyroidism, a history of cardiovascular or cerebrovascular disease, or a predisposition to hypotension. Close monitoring of cardiovascular status, including ECG changes, is recommended at all dosages. Many of the newer antidepressants, including bupropion and the selective serotonin reuptake inhibitors (SSRIs), are considerably less or minimally cardiotoxic and may be appropriate alternatives.

Major:

thioridazine

Thioridazine has a major potential interaction with History - Myocardial Infarction.

Phenothiazines may cause hypotension. Patients with pheochromocytoma, cerebral vascular or renal insufficiency, cardiovascular disease, or a severe cardiac reserve deficiency (e.g., mitral insufficiency) may be more prone to hypotensive reactions. Close monitoring is recommended during treatment if used in at-risk patients; some products may be contraindicated (e.g., thioridazine). Large doses and parenteral administration should be used cautiously, or avoided, in patients with impaired cardiovascular systems.

Hyperthyroidism

Major:

doxepin

Doxepin has a major potential interaction with Hyperthyroidism.

Tricyclic and tetracyclic antidepressants (TCAs) may cause orthostatic hypotension, reflex tachycardia, syncope, and dizziness, particularly during initiation of therapy or rapid escalation of dosage. Imipramine appears to have the greatest propensity to induce these effects, while secondary amines such as nortriptyline may do so less frequently. Tolerance to the hypotensive effects often develops after a few doses to a few weeks. Rarely, collapse and sudden death have occurred secondary to severe hypotension. Other reported adverse cardiovascular effects include tachycardia, arrhythmias, heart block, hypertension, thrombosis, thrombophlebitis, myocardial infarction, strokes, congestive heart failure, and ECG abnormalities such as PR and QT interval prolongation. Therapy with TCAs should be avoided during the acute recovery phase following myocardial infarction, and should be administered only with extreme caution in patients with hyperthyroidism, a history of cardiovascular or cerebrovascular disease, or a predisposition to hypotension. Close monitoring of cardiovascular status, including ECG changes, is recommended at all dosages. Many of the newer antidepressants, including bupropion and the selective serotonin reuptake inhibitors (SSRIs), are considerably less or minimally cardiotoxic and may be appropriate alternatives.

Moderate:

doxepin

Doxepin has a moderate potential interaction with Hyperthyroidism.

Most tricyclic antidepressants should be administered with caution in hyperthyroid patients or those receiving thyroid medication as they may develop arrhythmias when these drugs are given.

Hypoglycemia

Moderate:

doxepin

Doxepin has a moderate potential interaction with Hypoglycemia.

There have been reports of both elevation and lowering of blood sugar levels in patients receiving tricyclic antidepressants. These drugs should be used with caution in patients with hypoglycemia, hyperglycemia or diabetes. Monitoring sugar levels is recommended.

Hypokalemia

Major:

thioridazine

Thioridazine has a major potential interaction with Hypokalemia.

The use of thioridazine is contraindicated in patients with congenital or acquired QT interval prolongation syndromes or a history of cardiac arrhythmias. Thioridazine can prolong the QT interval of the electrocardiogram in a dose-related manner. The risk of torsade de pointes is progressively increased as the degree of prolongation becomes greater. In a crossover study of nine patients, a single 50 mg dose of thioridazine increased the QTc interval by a mean maximum of 23 msec compared to placebo. During postmarketing experience, torsade de pointes and sudden death have been reported, although a causal relationship has not been determined. The manufacturer states that thioridazine should not be administered in patients with a baseline QTc interval greater than 450 msec, and that it should be discontinued in patients with QTc measurements exceeding 500 msec during therapy. Electrolyte disturbances such as hypokalemia and hypomagnesemia may augment the prolongation effect of thioridazine on the QT interval and should be corrected prior to institution of therapy. Patients who experience frequent, severe, or prolonged diarrhea may be subject to electrolyte losses and should be followed closely and managed accordingly during therapy with thioridazine.

Hypotension

Major:

doxepin

Doxepin has a major potential interaction with Hypotension.

Tricyclic and tetracyclic antidepressants (TCAs) may cause orthostatic hypotension, reflex tachycardia, syncope, and dizziness, particularly during initiation of therapy or rapid escalation of dosage. Imipramine appears to have the greatest propensity to induce these effects, while secondary amines such as nortriptyline may do so less frequently. Tolerance to the hypotensive effects often develops after a few doses to a few weeks. Rarely, collapse and sudden death have occurred secondary to severe hypotension. Other reported adverse cardiovascular effects include tachycardia, arrhythmias, heart block, hypertension, thrombosis, thrombophlebitis, myocardial infarction, strokes, congestive heart failure, and ECG abnormalities such as PR and QT interval prolongation. Therapy with TCAs should be avoided during the acute recovery phase following myocardial infarction, and should be administered only with extreme caution in patients with hyperthyroidism, a history of cardiovascular or cerebrovascular disease, or a predisposition to hypotension. Close monitoring of cardiovascular status, including ECG changes, is recommended at all dosages. Many of the newer antidepressants, including bupropion and the selective serotonin reuptake inhibitors (SSRIs), are considerably less or minimally cardiotoxic and may be appropriate alternatives.

Major:

thioridazine

Thioridazine has a major potential interaction with Hypotension.

Phenothiazines may cause hypotension. Patients with pheochromocytoma, cerebral vascular or renal insufficiency, cardiovascular disease, or a severe cardiac reserve deficiency (e.g., mitral insufficiency) may be more prone to hypotensive reactions. Close monitoring is recommended during treatment if used in at-risk patients; some products may be contraindicated (e.g., thioridazine). Large doses and parenteral administration should be used cautiously, or avoided, in patients with impaired cardiovascular systems.

Liver Disease

Major:

thioridazine

Thioridazine has a major potential interaction with Liver Disease.

Therapy with phenothiazines should be administered cautiously or are contraindicated in patients with preexisting liver disease or with a history of jaundice due to phenothiazine hypersensitivity. Patients with a history of hepatic encephalopathy due to cirrhosis may have increased sensitivity to the central nervous system effects of some phenothiazines (e.g., chlorpromazine). Treatment should be discontinued if jaundice occurs.

Moderate:

doxepin

Doxepin has a moderate potential interaction with Liver Disease.

Tricyclic and tetracyclic antidepressants (TCAs) are known to undergo metabolism in the liver. Some of the metabolites, such as those of imipramine, clomipramine and desipramine, may be pharmacologically active. Many of the metabolites are also excreted by the kidney. There are very limited data concerning the use of TCAs in patients with renal and/or liver disease. Therapy with TCAs should be administered cautiously in patients with significantly impaired renal or hepatic function. Dosage adjustments may be necessary.

Moderate:

doxepin

Doxepin has a moderate potential interaction with Liver Disease.

In general, anxiolytics, sedatives and hypnotics are extensively metabolized by the liver. Their plasma clearance may be decreased and their half-life prolonged in patients with impaired hepatic function. Therapy with these drugs should be administered cautiously in patients with liver disease (some are not recommended in severe liver impairment), and the dosage should be adjusted accordingly. Laboratory testing is recommended prior and during treatment.

Moderate:

doxepin

Doxepin has a moderate potential interaction with Liver Disease.

Some anxiolytics, sedatives and hypnotics are extensively metabolized by the liver, and excreted in the urine. Patients with impaired renal and/or hepatic function may be at greater risk for adverse effects, including central nervous system and respiratory depression, due to drug and metabolite accumulation. Therapy with these drugs should be administered cautiously in such patients, with careful dose selection usually starting at the low end of the dosing range.

Moderate:

doxepin

Doxepin has a moderate potential interaction with Liver Disease.

In general, tricyclic antidepressants should be used with caution in patients with liver or renal disease, as these drugs are metabolized and excreted through the liver and kidneys. Dose selection, especially in the elderly patients that might have liver or renal dysfunction, should usually be limited to the smallest effective total daily dose. Some tricyclic antidepressants such as clomipramine and nortriptyline have occasionally been associated with elevations in SGOT (AST) and SGPT (ALT), and other hepatic adverse events such as jaundice. Although serious liver injury has only been reported rarely, therapy with these drugs should be administered cautiously in patients with preexisting liver disease and periodic monitoring of liver enzyme levels is recommended.

Magnesium Imbalance

Major:

thioridazine

Thioridazine has a major potential interaction with Magnesium Imbalance.

The use of thioridazine is contraindicated in patients with congenital or acquired QT interval prolongation syndromes or a history of cardiac arrhythmias. Thioridazine can prolong the QT interval of the electrocardiogram in a dose-related manner. The risk of torsade de pointes is progressively increased as the degree of prolongation becomes greater. In a crossover study of nine patients, a single 50 mg dose of thioridazine increased the QTc interval by a mean maximum of 23 msec compared to placebo. During postmarketing experience, torsade de pointes and sudden death have been reported, although a causal relationship has not been determined. The manufacturer states that thioridazine should not be administered in patients with a baseline QTc interval greater than 450 msec, and that it should be discontinued in patients with QTc measurements exceeding 500 msec during therapy. Electrolyte disturbances such as hypokalemia and hypomagnesemia may augment the prolongation effect of thioridazine on the QT interval and should be corrected prior to institution of therapy. Patients who experience frequent, severe, or prolonged diarrhea may be subject to electrolyte losses and should be followed closely and managed accordingly during therapy with thioridazine.

Mania

Moderate:

doxepin

Doxepin has a moderate potential interaction with Mania.

Tricyclic antidepressants (TCAs) may aggravate symptoms of psychosis in schizophrenic patients, particularly those with paranoid symptomatology. Depressed patients, usually those with bipolar disorder, may experience a switch from depression to mania or hypomania. These occurrences have also been reported rarely with the tetracyclic antidepressant, maprotiline. Therapy with these agents should be administered cautiously in patients with schizophrenia, bipolar disorder, or a history of mania.

Neuroleptic Malignant Syndrome

Moderate:

thioridazine

Thioridazine has a moderate potential interaction with Neuroleptic Malignant Syndrome.

Therapy with phenothiazines may precipitate or aggravate a potentially fatal symptom complex known as neuroleptic malignant syndrome (NMS). Treatment should not be initiated in patients with active NMS, and should be immediately discontinued if currently administered in such patients. In patients with a history of NMS, introduction or reintroduction of phenothiazines should be carefully considered, since NMS may recur.

Neutropenia

Moderate:

doxepin

Doxepin has a moderate potential interaction with Neutropenia.

The use of some tricyclic antidepressants has been associated with neutropenia (ANC < 500/mm3) and agranulocytosis (ANC < 500/mm3). Leukocyte and differential blood counts should be performed in patients that develop fever and sore throat during treatment. Therapy should be discontinued if there is evidence of pathologic neutrophil depression.

Pheochromocytoma

Major:

doxepin

Doxepin has a major potential interaction with Pheochromocytoma.

Tricyclic and tetracyclic antidepressants (TCAs) may potentiate the effects of circulating catecholamines. Enhanced sympathetic activity can provoke hypertensive crises in patients with pheochromocytoma or other tumors of the adrenal medulla, such as some neuroblastomas. Therapy with TCAs should be administered cautiously in patients with these tumors.

Major:

thioridazine

Thioridazine has a major potential interaction with Pheochromocytoma.

Phenothiazines may cause hypotension. Patients with pheochromocytoma, cerebral vascular or renal insufficiency, cardiovascular disease, or a severe cardiac reserve deficiency (e.g., mitral insufficiency) may be more prone to hypotensive reactions. Close monitoring is recommended during treatment if used in at-risk patients; some products may be contraindicated (e.g., thioridazine). Large doses and parenteral administration should be used cautiously, or avoided, in patients with impaired cardiovascular systems.

Renal Dysfunction

Moderate:

doxepin

Doxepin has a moderate potential interaction with Renal Dysfunction.

Some anxiolytics, sedatives and hypnotics are extensively metabolized by the liver, and excreted in the urine. Patients with impaired renal and/or hepatic function may be at greater risk for adverse effects, including central nervous system and respiratory depression, due to drug and metabolite accumulation. Therapy with these drugs should be administered cautiously in such patients, with careful dose selection usually starting at the low end of the dosing range.

Moderate:

doxepin

Doxepin has a moderate potential interaction with Renal Dysfunction.

In general, tricyclic antidepressants should be used with caution in patients with liver or renal disease, as these drugs are metabolized and excreted through the liver and kidneys. Dose selection, especially in the elderly patients that might have liver or renal dysfunction, should usually be limited to the smallest effective total daily dose. Some tricyclic antidepressants such as clomipramine and nortriptyline have occasionally been associated with elevations in SGOT (AST) and SGPT (ALT), and other hepatic adverse events such as jaundice. Although serious liver injury has only been reported rarely, therapy with these drugs should be administered cautiously in patients with preexisting liver disease and periodic monitoring of liver enzyme levels is recommended.

Moderate:

doxepin

Doxepin has a moderate potential interaction with Renal Dysfunction.

Tricyclic and tetracyclic antidepressants (TCAs) are known to undergo metabolism in the liver. Some of the metabolites, such as those of imipramine, clomipramine and desipramine, may be pharmacologically active. Many of the metabolites are also excreted by the kidney. There are very limited data concerning the use of TCAs in patients with renal and/or liver disease. Therapy with TCAs should be administered cautiously in patients with significantly impaired renal or hepatic function. Dosage adjustments may be necessary.

Respiratory Arrest

Major:

thioridazine

Thioridazine has a major potential interaction with Respiratory Arrest.

The use of phenothiazines is contraindicated in comatose patients and patients with severe central nervous system depression. Phenothiazines may potentiate the CNS and respiratory depression in these patients.

Schizophrenia

Moderate:

doxepin

Doxepin has a moderate potential interaction with Schizophrenia.

Some tricyclic antidepressants have shown to cause activation or exacerbation of psychosis in schizophrenic patients. A dosage reduction might be required.

Moderate:

doxepin

Doxepin has a moderate potential interaction with Schizophrenia.

Tricyclic antidepressants (TCAs) may aggravate symptoms of psychosis in schizophrenic patients, particularly those with paranoid symptomatology. Depressed patients, usually those with bipolar disorder, may experience a switch from depression to mania or hypomania. These occurrences have also been reported rarely with the tetracyclic antidepressant, maprotiline. Therapy with these agents should be administered cautiously in patients with schizophrenia, bipolar disorder, or a history of mania.

Seizures

Moderate:

thioridazine

Thioridazine has a moderate potential interaction with Seizures.

Phenothiazines can lower the seizure threshold. Caution is recommended during administration in patients with a history of convulsive disorders or EEG abnormalities. Anticonvulsant therapy should be maintained or adequately adjusted during phenothiazine treatment.

Tardive Dyskinesia

Moderate:

doxepin

Doxepin has a moderate potential interaction with Tardive Dyskinesia.

Tricyclic and tetracyclic antidepressants (TCAs) have anticholinergic activity, to which elderly patients are particularly sensitive. Tertiary amines such as amitriptyline and trimipramine tend to exhibit greater anticholinergic effects than other agents in the class. As with other drugs that possess anticholinergic activity, TCAs may aggravate tardive dyskinesia or induce previously suppressed symptoms. Patients with tardive dyskinesia requiring therapy with TCAs should be monitored for exacerbation of the condition.

Urinary Retention

Major:

doxepin

Doxepin has a major potential interaction with Urinary Retention.

Tricyclic and tetracyclic antidepressants (TCAs) have anticholinergic activity, to which elderly patients are particularly sensitive. Tertiary amines such as amitriptyline and trimipramine tend to exhibit greater anticholinergic effects than other agents in the class. Therapy with TCAs should be administered cautiously in patients with preexisting conditions that are likely to be exacerbated by anticholinergic activity, such as urinary retention or obstruction; angle-closure glaucoma, untreated intraocular hypertension, or uncontrolled primary open-angle glaucoma; and gastrointestinal obstructive disorders. In patients with angle-closure glaucoma, even average doses can precipitate an attack. Glaucoma should be treated and under control prior to initiation of therapy with TCAs, and intraocular pressure monitored during therapy.

Major:

doxepin

Doxepin has a major potential interaction with Urinary Retention.

The use of doxepin is contraindicated in patients with glaucoma, or a tendency to urinary retention. These disorders should be ruled out before starting treatment, especially in elderly patients.

Moderate:

doxepin

Doxepin has a moderate potential interaction with Urinary Retention.

Some hypnotic drugs can have an anticholinergic effect and should be used with caution in patients with glaucoma, and trouble urinating due to retention or enlarged prostate.

Moderate:

doxepin

Doxepin has a moderate potential interaction with Urinary Retention.

Due to their anticholinergic properties, tricyclic antidepressants should be administered with caution in patients with history of urinary retention. Particularly doxepin hydrochloride capsules are contraindicated in patients with tendency to urinary retention.

Valvular Heart Disease

Major:

thioridazine

Thioridazine has a major potential interaction with Valvular Heart Disease.

Phenothiazines may cause hypotension. Patients with pheochromocytoma, cerebral vascular or renal insufficiency, cardiovascular disease, or a severe cardiac reserve deficiency (e.g., mitral insufficiency) may be more prone to hypotensive reactions. Close monitoring is recommended during treatment if used in at-risk patients; some products may be contraindicated (e.g., thioridazine). Large doses and parenteral administration should be used cautiously, or avoided, in patients with impaired cardiovascular systems.

More resources

doxepin

A total of 735 drugs are known to interact with doxepin.

thioridazine

A total of 778 drugs are known to interact with thioridazine.

Drug Interaction Classification

These classifications are only a guideline. The relevance of a particular drug interaction to a specific individual is difficult to determine. Always consult your healthcare provider before starting or stopping any medication.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.
Unknown No interaction information available.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.