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Interactions between Fluphenazine and Ritalin

1 drug interaction and 45 additional warnings found for the following 2 drugs:

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Drug interactions

Moderate drug interactions

Moderate:

fluPHENAZine methylphenidate

Applies to: fluphenazine and Ritalin (methylphenidate)
Generally avoid

Phenothiazines may antagonize the pharmacologic effects of amphetamine, amphetamine derivatives, and other centrally-acting sympathomimetic agents (i.e., CNS stimulants). Conversely, these agents may diminish the neuroleptic efficacy of phenothiazines. The exact mechanism of interaction is unknown but may involve opposing effects on dopaminergic activity. Several clinical studies have demonstrated the reduction or lack of effect of amphetamines on weight loss in obese psychiatric patients treated with chlorpromazine and other neuroleptic agents. In one of these studies, dextroamphetamine also had no effect on sleep patterns. As for the reverse interaction, it is uncertain whether CNS stimulants actually antagonize the neuroleptic effect of phenothiazines, since CNS stimulants alone have been reported to cause or aggravate preexisting psychotic symptoms. Finally, it is conceivable that, because of their sympathomimetic effects, CNS stimulants may also potentiate the arrhythmogenicity of phenothiazines. A case of fatal ventricular arrhythmia was reported in a patient treated chronically with thioridazine who ingested a single capsule containing phenylpropanolamine 50 mg and chlorpheniramine 4 mg. However, a causal relationship was not established.

Management

Amphetamine, amphetamine derivatives, and other CNS stimulants should generally not be used, particularly for weight reduction, in patients treated with phenothiazines.

References (34)
  1. Reid AA (1964) "Pharmacological antagonism between chlorpromazine and phenmetrazine in mental hospital patients." Med J Aust, 1, p. 187-8
  2. Sletten IW, Ognjanov V, Menendez S, Sundland D, El-Toumi A (1967) "Weight reduction with chlorphentermine and phenmetrazine in obese psychiatric patients during chlorpromazine therapy." Curr Ther Res Clin Exp, 9, p. 570-5
  3. Chouinard G, Ghadirian AM, Jones BD (1978) "Death attributed to ventricular arrhythmia induced by thioridazine in combination with a single Contac*C capsule." Can Med Assoc J, 119, p. 729-31
  4. Casey JF, Hollister LE, Klett CJ, Lasky JJ, Caffey EM (1961) "Combined drug therapy of chronic schizophrenics." Am J Psychiatry, 177, p. 997
  5. Modell W, Hussar AE (1965) "Failure of dextroamphetamine sulfate to incluence eating and sleeping patterns in obese schizophrenic patients." JAMA, 193, p. 275-8
  6. Angrist B, Lee HK, Gershon S (1974) "The antagonism of amphetamine-induced symptomatology by a neuroleptic." Am J Psychiatry, 131, p. 817-9
  7. Cornelius JR, Soloff PH, Reynolds CF, 3d (1984) "Paranoia, homicidal behavior, and seizures associated with phenylpropanolamine." Am J Psychiatry, 141, p. 120-1
  8. Achor MB, Extein I (1981) "Diet aids, mania, and affective illness" Am J Psychiatry, 138, p. 392
  9. Schaffer CB, Pauli MW (1980) "Psychotic reaction caused by proprietary oral diet agents." Am J Psychiatry, 137, p. 1256-7
  10. Grieger TA, Clayton AH, Goyer PF (1990) "Affective disorder following use of phenylpropanolamine" Am J Psychiatry, 147, p. 367-8
  11. Dietz AJ, Jr (1981) "Amphetamine-like reactions to phenylpropanolamine." JAMA, 245, p. 601-2
  12. Norvenius G, Widerlov E, Lonnerholm G (1979) "Phenylpropanolamine and mental disturbances" Lancet, 2, p. 1367-8
  13. Mueller SM (1983) "Neurologic complications of phenylpropanolamine use." Neurology, 33, p. 650-2
  14. Lake CR, Tenglin R, Chernow B, Holloway HC (1983) "Psychomotor stimulant-induced mania in a genetically predisposed patient: a review of the literature and report of a case." J Clin Psychopharmacol, 3, p. 97-100
  15. Lake CR (1991) "Manic psychosis after coffee and phenylpropanolamine." Biol Psychiatry, 30, p. 401-4
  16. Lambert MT (1987) "Paranoid psychoses after abuse of proprietary cold remedies." Br J Psychiatry, 151:, p. 548-50
  17. Wharton BK (1970) "Nasal decongestants and paranoid psychosis." Br J Psychiatry, 117, p. 439-40
  18. Dewsnap P, Libby G (1992) "A case of affective psychosis after routine use of proprietary cold remedy containing phenylpropanolamine" Hum Exp Toxicol, 11, p. 295-6
  19. Finton CK, Barton M, Chernow B (1982) "Possible adverse effects of phenylpropanolamine (diet pills) on sympathetic nervous system function--caveat emptor!" Mil Med, 147, p. 1072
  20. Stroe AE, Hall J, Amin F (1995) "Psychotic episode related to phenylpropanolamine and amantadine in a healthy female." Gen Hosp Psychiatry, 17, p. 457-8
  21. Marshall RD, Douglas CJ (1994) "Phenylpropanolamine-induced psychosis: potential predisposing factors." Gen Hosp Psychiatry, 16, p. 358-60
  22. (2001) "Product Information. Fastin (phentermine)." SmithKline Beecham
  23. (2001) "Product Information. Cylert (pemoline)." Abbott Pharmaceutical
  24. (2001) "Product Information. Ritalin (methylphenidate)." Novartis Pharmaceuticals
  25. (2001) "Product Information. Desoxyn (methamphetamine)." Abbott Pharmaceutical
  26. (2001) "Product Information. Dexedrine (dextroamphetamine)." SmithKline Beecham
  27. (2001) "Product Information. Adderall (amphetamine-dextroamphetamine)." Shire Richwood Pharmaceutical Company Inc
  28. (2001) "Product Information. Didrex (benzphetamine)." Pharmacia and Upjohn
  29. (2001) "Product Information. Prelu-2 (phendimetrazine)." Boehringer-Ingelheim
  30. (2001) "Product Information. Tenuate (diethylpropion)." Aventis Pharmaceuticals
  31. (2001) "Product Information. Sanorex (mazindol)." Novartis Pharmaceuticals
  32. Markowitz JS, Patrick KS (2001) "Pharmacokinetic and pharmacodynamic drug interactions in the treatment of attention-deficit hyperactivity disorder." Clin Pharmacokinet, 40, p. 753-72
  33. (2001) "Product Information. Focalin (dexmethylphenidate)." Mikart Inc
  34. (2007) "Product Information. Vyvanse (lisdexamfetamine)." Shire US Inc

Food/lifestyle interactions

Moderate food/lifestyle interactions

Moderate:

methylphenidate Food/Lifestyle

Applies to: Ritalin (methylphenidate)
Generally avoid

Alcohol may exacerbate the adverse central nervous system effects of psychoactive drugs, including methylphenidate.

Generally avoid

Consumption of alcohol while taking certain sustained-release formulations of methylphenidate may cause rapid release of the drug, resulting in increased systemic levels of methylphenidate. In vitro studies have been conducted using Metadate CD 60 mg and Ritalin LA 40 mg capsules, as well as Concerta 18 mg tablet. At an alcohol concentration of 40%, an increase in the release rate of methylphenidate was observed in the first hour for Metadate CD and Ritalin LA, resulting in 84% and 98% of the methylphenidate being released, respectively. In contrast, there was no increased release of methylphenidate in the first hour for Concerta. These results are considered to be representative of the other available strengths of the corresponding product.

Management

Patients treated with methylphenidate should be advised to avoid alcohol or medications that contain alcohol.

References (3)
  1. (2022) "Product Information. Metadate CD (methylphenidate)." Celltech Pharmaceuticals Inc
  2. (2002) "Product Information. Concerta (methylphenidate)." Alza
  3. (2013) "Product Information. Ritalin LA (methylphenidate)." Quality Care Products/Lake Erie Medical
Moderate:

fluPHENAZine Alcohol (Ethanol)

Applies to: fluphenazine
Generally avoid

Concurrent use of ethanol and phenothiazines may result in additive CNS depression and psychomotor impairment. Also, ethanol may precipitate dystonic reactions in patients who are taking phenothiazines. The two drugs probably act on different sites in the brain, although the exact mechanism of the interaction is not known.

Management

Patients should be advised to avoid alcohol during phenothiazine therapy.

References (2)
  1. Lutz EG (1976) "Neuroleptic-induced akathisia and dystonia triggered by alcohol." JAMA, 236, p. 2422-3
  2. Freed E (1981) "Alcohol-triggered-neuroleptic-induced tremor, rigidity and dystonia." Med J Aust, 2, p. 44-5

Disease interactions

43 potential interactions Applies to: 32 conditions, including High Blood Pressure, Depression, Anxiety and Stress, Seizures, and Arrhythmia.

Acute Alcohol Intoxication

Major:

fluphenazine

fluPHENAZine 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:

fluphenazine

fluPHENAZine 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.

Major:

Ritalin

The methylphenidate in Ritalin has a major potential interaction with Alcoholism.

CNS stimulants (especially amphetamines) have a high potential for abuse and misuse, which can lead to development of a substance use disorder, including addiction. Misuse and abuse of CNS stimulants can result in overdose and death; this risk is increased with higher doses or unapproved methods of administration (e.g., snorting, injection). Before prescribing a CNS stimulant, each patient's risk for abuse, misuse, and addiction should be assessed. Throughout therapy, it is recommended to reassess each patient's risk and frequently monitor for signs/symptoms of abuse, misuse, and addiction. Therapy with CNS stimulants should be administered cautiously, if at all, in patients with a history of alcohol or substance abuse. The use of some agents is contraindicated in patients with a history of drug abuse.

Altered Consciousness

Major:

fluphenazine

fluPHENAZine 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.

Anxiety and Stress

Major:

Ritalin

The methylphenidate in Ritalin has a major potential interaction with Anxiety and Stress.

Some CNS stimulants are contraindicated in patients with marked agitation and/or anxiety since these symptoms may be aggravated. CNS stimulants may also exacerbate symptoms of behavior disturbance and thought disorder in psychotic patients, particularly children. Therapy with CNS stimulants should be administered cautiously in patients with a history of psychosis or a predisposition to agitated states.

Arrhythmia

Major:

fluphenazine

fluPHENAZine 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.

Bone Marrow Depression/Low Blood Counts

Major:

fluphenazine

fluPHENAZine 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:

Ritalin

The methylphenidate in Ritalin has a moderate potential interaction with Bone Marrow Depression/Low Blood Counts.

Hematologic toxicity, including thrombocytopenia, easy bruisability, epistaxis, leukopenia, anemia and eosinophilia, has been reported rarely during use of methylphenidate. However, a causal relationship has not been established. Therapy with methylphenidate (racemic) or dexmethylphenidate (the more pharmacologically active d-enantiomer) should be administered cautiously in patients with preexisting blood dyscrasias or bone marrow suppression. Periodic hematologic monitoring may be appropriate in all patients during prolonged therapy.

Breast Cancer

Moderate:

fluphenazine

fluPHENAZine 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:

fluphenazine

fluPHENAZine 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

Moderate:

fluphenazine

fluPHENAZine 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:

fluphenazine

fluPHENAZine 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.

Dementia

Major:

fluphenazine

fluPHENAZine 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:

Ritalin

The methylphenidate in Ritalin has a major potential interaction with Depression.

The use of CNS stimulants can cause psychotic symptoms, suicidal ideation, and aggression, and can exacerbate symptoms of behavior disturbance and thought disorder; CNS stimulants may induce a manic or mixed episode in patients with bipolar disorder. Psychiatric symptoms have been reported in patients with and without history of psychiatric disorders. All patients (particularly those with psychotic or bipolar disorders) should be monitored closely, especially during treatment initiation and at times of dose changes. Extreme caution should be exercised when CNS stimulants are given to patients with a history of psychosis, depression, mania, or bipolar disorder. Prior to initiating therapy, all patients should be screened for risk factors for developing a manic episode (e.g., comorbid or history of depressive symptoms or family history of suicide, bipolar disease, or depression). If any psychiatric symptoms emerge or are exacerbated, treatment suspension should be considered. Some CNS stimulants are contraindicated in patients with marked agitation or anxiety.

Drug Dependence

Major:

Ritalin

The methylphenidate in Ritalin has a major potential interaction with Drug Dependence.

CNS stimulants (especially amphetamines) have a high potential for abuse and misuse, which can lead to development of a substance use disorder, including addiction. Misuse and abuse of CNS stimulants can result in overdose and death; this risk is increased with higher doses or unapproved methods of administration (e.g., snorting, injection). Before prescribing a CNS stimulant, each patient's risk for abuse, misuse, and addiction should be assessed. Throughout therapy, it is recommended to reassess each patient's risk and frequently monitor for signs/symptoms of abuse, misuse, and addiction. Therapy with CNS stimulants should be administered cautiously, if at all, in patients with a history of alcohol or substance abuse. The use of some agents is contraindicated in patients with a history of drug abuse.

Gastrointestinal Obstruction

Moderate:

Ritalin

The methylphenidate in Ritalin has a moderate potential interaction with Gastrointestinal Obstruction.

The extended-release formulation of methylphenidate (Concerta) contains a non-deformable material. There have been rare reports of obstructive symptoms in patients with known strictures following the ingestion of similar sustained-release products. The extended-release formulation of methylphenidate should ordinarily not be administered in patients with preexisting severe gastrointestinal narrowing or obstruction, whether pathologic or iatrogenic (e.g., small bowel inflammatory disease, "short gut" syndrome due to adhesions or decreased transit time, past history of peritonitis, cystic fibrosis, chronic intestinal pseudo-obstruction, or Meckel's diverticulum). The medication should only be used in patients who are able to swallow the tablet whole.

Glaucoma/Intraocular Hypertension

Major:

Ritalin

The methylphenidate in Ritalin has a major potential interaction with Glaucoma/Intraocular Hypertension.

The use of most CNS stimulants is contraindicated in patients with glaucoma, as these agents exhibit sympathomimetic activity and may induce mydriasis provoking an increase in intraocular pressure.

Heart Disease

Major:

Ritalin

The methylphenidate in Ritalin has a major potential interaction with Heart Disease.

Many CNS stimulants are contraindicated in patients with significant cardiovascular impairment such as uncompensated heart failure, severe coronary disease, severe hypertension (including that associated with hyperthyroidism or pheochromocytoma), cardiac structural abnormalities, serious arrhythmias, etc. Sudden death has been reported in patients with structural cardiac abnormalities or other serious cardiac disease who are treated with CNS stimulants at the recommended dosages for attention deficit hyperactivity disorder; use of these agents should be avoided in patients with known structural cardiac abnormalities, cardiomyopathy, serious cardiac arrhythmia, coronary artery disease, or other serious cardiac disease. Additionally, stroke, myocardial infarction, chest pain, syncope, arrhythmias, and other symptoms have been reported in adults under treatment. A careful assessment of the cardiovascular status should be done in patients being considered for treatment. This includes family history, physical exam, and further cardiac evaluation (EKG and echocardiogram). Patients who develop symptoms should have a detailed cardiac evaluation and if needed, treatment should be suspended.

High Blood Pressure

Major:

fluphenazine

fluPHENAZine 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.

Major:

Ritalin

The methylphenidate in Ritalin has a major potential interaction with High Blood Pressure.

CNS stimulants increase blood pressure and heart rate; the use of some agents may be contraindicated in patients with severe/uncontrolled hypertension. Caution should be used when administering to patients with preexisting high blood pressure (even mild hypertension) and other cardiovascular conditions. All patients under treatment should be regularly monitored for potential tachycardia and hypertension.

Major:

Ritalin

The methylphenidate in Ritalin has a major potential interaction with High Blood Pressure.

Many CNS stimulants are contraindicated in patients with significant cardiovascular impairment such as uncompensated heart failure, severe coronary disease, severe hypertension (including that associated with hyperthyroidism or pheochromocytoma), cardiac structural abnormalities, serious arrhythmias, etc. Sudden death has been reported in patients with structural cardiac abnormalities or other serious cardiac disease who are treated with CNS stimulants at the recommended dosages for attention deficit hyperactivity disorder; use of these agents should be avoided in patients with known structural cardiac abnormalities, cardiomyopathy, serious cardiac arrhythmia, coronary artery disease, or other serious cardiac disease. Additionally, stroke, myocardial infarction, chest pain, syncope, arrhythmias, and other symptoms have been reported in adults under treatment. A careful assessment of the cardiovascular status should be done in patients being considered for treatment. This includes family history, physical exam, and further cardiac evaluation (EKG and echocardiogram). Patients who develop symptoms should have a detailed cardiac evaluation and if needed, treatment should be suspended.

Major:

Ritalin

The methylphenidate in Ritalin has a major potential interaction with High Blood Pressure.

Methylphenidate (racemic) and dexmethylphenidate (the more pharmacologically active d-enantiomer) exhibit sympathomimetic activity and may elevate blood pressure and pulse rate. Therapy with these agents should be administered cautiously in patients with hypertension. Blood pressure should be monitored periodically during therapy.

History - Cerebrovascular Disease

Major:

fluphenazine

fluPHENAZine 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:

fluphenazine

fluPHENAZine 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:

Ritalin

The methylphenidate in Ritalin has a major potential interaction with Hyperthyroidism.

Many CNS stimulants are contraindicated in patients with significant cardiovascular impairment such as uncompensated heart failure, severe coronary disease, severe hypertension (including that associated with hyperthyroidism or pheochromocytoma), cardiac structural abnormalities, serious arrhythmias, etc. Sudden death has been reported in patients with structural cardiac abnormalities or other serious cardiac disease who are treated with CNS stimulants at the recommended dosages for attention deficit hyperactivity disorder; use of these agents should be avoided in patients with known structural cardiac abnormalities, cardiomyopathy, serious cardiac arrhythmia, coronary artery disease, or other serious cardiac disease. Additionally, stroke, myocardial infarction, chest pain, syncope, arrhythmias, and other symptoms have been reported in adults under treatment. A careful assessment of the cardiovascular status should be done in patients being considered for treatment. This includes family history, physical exam, and further cardiac evaluation (EKG and echocardiogram). Patients who develop symptoms should have a detailed cardiac evaluation and if needed, treatment should be suspended.

Hypotension

Major:

fluphenazine

fluPHENAZine 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:

fluphenazine

fluPHENAZine 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:

Ritalin

The methylphenidate in Ritalin has a moderate potential interaction with Liver Disease.

In general, CNS stimulants 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 CNS stimulants should be administered cautiously in patients with moderate to severe liver disease, and the dosage should be adjusted accordingly in certain agents. Additionally, postmarketing reports have shown that atomoxetine can cause severe liver injury; laboratory testing should be done at the first sign/symptom of liver dysfunction (jaundice, dark urine, upper quadrant tenderness) and treatment should be discontinued in patients with evidence of liver injury.

Neuroleptic Malignant Syndrome

Moderate:

fluphenazine

fluPHENAZine 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.

Neurosis

Major:

Ritalin

The methylphenidate in Ritalin has a major potential interaction with Neurosis.

Some CNS stimulants are contraindicated in patients with marked agitation and/or anxiety since these symptoms may be aggravated. CNS stimulants may also exacerbate symptoms of behavior disturbance and thought disorder in psychotic patients, particularly children. Therapy with CNS stimulants should be administered cautiously in patients with a history of psychosis or a predisposition to agitated states.

Peripheral Arterial Disease

Major:

Ritalin

The methylphenidate in Ritalin has a major potential interaction with Peripheral Arterial Disease.

Many CNS stimulants are contraindicated in patients with significant cardiovascular impairment such as uncompensated heart failure, severe coronary disease, severe hypertension (including that associated with hyperthyroidism or pheochromocytoma), cardiac structural abnormalities, serious arrhythmias, etc. Sudden death has been reported in patients with structural cardiac abnormalities or other serious cardiac disease who are treated with CNS stimulants at the recommended dosages for attention deficit hyperactivity disorder; use of these agents should be avoided in patients with known structural cardiac abnormalities, cardiomyopathy, serious cardiac arrhythmia, coronary artery disease, or other serious cardiac disease. Additionally, stroke, myocardial infarction, chest pain, syncope, arrhythmias, and other symptoms have been reported in adults under treatment. A careful assessment of the cardiovascular status should be done in patients being considered for treatment. This includes family history, physical exam, and further cardiac evaluation (EKG and echocardiogram). Patients who develop symptoms should have a detailed cardiac evaluation and if needed, treatment should be suspended.

Pheochromocytoma

Major:

fluphenazine

fluPHENAZine 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.

Major:

Ritalin

The methylphenidate in Ritalin has a major potential interaction with Pheochromocytoma.

Many CNS stimulants are contraindicated in patients with significant cardiovascular impairment such as uncompensated heart failure, severe coronary disease, severe hypertension (including that associated with hyperthyroidism or pheochromocytoma), cardiac structural abnormalities, serious arrhythmias, etc. Sudden death has been reported in patients with structural cardiac abnormalities or other serious cardiac disease who are treated with CNS stimulants at the recommended dosages for attention deficit hyperactivity disorder; use of these agents should be avoided in patients with known structural cardiac abnormalities, cardiomyopathy, serious cardiac arrhythmia, coronary artery disease, or other serious cardiac disease. Additionally, stroke, myocardial infarction, chest pain, syncope, arrhythmias, and other symptoms have been reported in adults under treatment. A careful assessment of the cardiovascular status should be done in patients being considered for treatment. This includes family history, physical exam, and further cardiac evaluation (EKG and echocardiogram). Patients who develop symptoms should have a detailed cardiac evaluation and if needed, treatment should be suspended.

Psychosis

Major:

Ritalin

The methylphenidate in Ritalin has a major potential interaction with Psychosis.

Some CNS stimulants are contraindicated in patients with marked agitation and/or anxiety since these symptoms may be aggravated. CNS stimulants may also exacerbate symptoms of behavior disturbance and thought disorder in psychotic patients, particularly children. Therapy with CNS stimulants should be administered cautiously in patients with a history of psychosis or a predisposition to agitated states.

Major:

Ritalin

The methylphenidate in Ritalin has a major potential interaction with Psychosis.

The use of CNS stimulants can cause psychotic symptoms, suicidal ideation, and aggression, and can exacerbate symptoms of behavior disturbance and thought disorder; CNS stimulants may induce a manic or mixed episode in patients with bipolar disorder. Psychiatric symptoms have been reported in patients with and without history of psychiatric disorders. All patients (particularly those with psychotic or bipolar disorders) should be monitored closely, especially during treatment initiation and at times of dose changes. Extreme caution should be exercised when CNS stimulants are given to patients with a history of psychosis, depression, mania, or bipolar disorder. Prior to initiating therapy, all patients should be screened for risk factors for developing a manic episode (e.g., comorbid or history of depressive symptoms or family history of suicide, bipolar disease, or depression). If any psychiatric symptoms emerge or are exacerbated, treatment suspension should be considered. Some CNS stimulants are contraindicated in patients with marked agitation or anxiety.

Renal Dysfunction

Moderate:

fluphenazine

fluPHENAZine has a moderate potential interaction with Renal Dysfunction.

Phenothiazines should be used with caution in patients with renal dysfunction. Patients with renal insufficiency may be more prone to hypotension. Periodic renal function tests are recommended for all patients during prolonged therapy.

Moderate:

Ritalin

The methylphenidate in Ritalin has a moderate potential interaction with Renal Dysfunction.

Overall CNS stimulants should be administered with caution in patients with significantly impaired renal function as the reduction in the rate of elimination may alter the therapeutic response. The dosage should be adjusted accordingly in certain agents.

Respiratory Arrest

Major:

fluphenazine

fluPHENAZine 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.

Seizures

Major:

Ritalin

The methylphenidate in Ritalin has a major potential interaction with Seizures.

There is some clinical evidence that methylphenidate may lower the seizure threshold, occasionally even in patients without a history of seizures or prior EEG abnormalities. Therapy with methylphenidate (racemic) or dexmethylphenidate (the more pharmacologically active d-enantiomer) should be administered cautiously in patients with or predisposed to seizures. The medication should be discontinued if seizures occur during its use.

Moderate:

fluphenazine

fluPHENAZine 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.

Moderate:

Ritalin

The methylphenidate in Ritalin has a moderate potential interaction with Seizures.

Due to general central nervous system stimulation, therapy with CNS stimulant drugs may cause seizures. These drugs may lower the convulsive threshold in patients with history of seizures, with prior electroencephalogram (EEG) abnormalities without seizures, and very rarely, without history of seizures and no prior EEG evidence of seizures. Therapy with CNS stimulants should be used with caution in patients with or predisposed to seizures. If seizures occur, therapy should be discontinued.

Tic Disorder

Major:

Ritalin

The methylphenidate in Ritalin has a major potential interaction with Tic Disorder.

CNS stimulants have been reported to worsen Tourette's syndrome and exacerbate motor and verbal tics. Before initiating therapy, it is recommended to assess family history and clinically evaluate patients for tics or Tourette's syndrome. Therapy with CNS stimulants, if necessary, should be administered cautiously in patients with tic disorders or family history of Tourette's syndrome. The manufacturers of the CNS stimulants, methylphenidate (racemic) and dexmethylphenidate (the more pharmacologically active d-enantiomer), consider their use to be contraindicated in such patients.

Valvular Heart Disease

Major:

fluphenazine

fluPHENAZine 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

fluphenazine

A total of 790 drugs are known to interact with fluphenazine.

Ritalin

A total of 216 drugs are known to interact with Ritalin.

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.