Interactions between Myophen and Perphenazine

Perphenazine 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.

The acetaminophen in Myophen has a major potential interaction with Alcoholism.

Chronic alcohol abusers may be at increased risk of hepatotoxicity during treatment with acetaminophen (APAP). Severe liver injury, including cases of acute liver failure resulting in liver transplant and death, has been reported in patients using acetaminophen. Therapy with acetaminophen should be administered cautiously, if at all, in patients who consume three or more alcoholic drinks a day. In general, patients should avoid drinking alcohol while taking acetaminophen-containing medications. Patients should be warned not to exceed the maximum recommended total daily dosage of acetaminophen (4 g/day in adults and children 12 years of age or older), and to read all prescription and over-the-counter medication labels to ensure they are not taking multiple acetaminophen-containing products, or check with a healthcare professional if they are unsure. They should also be advised to seek medical attention if they experience signs and symptoms of liver injury such as fever, rash, anorexia, nausea, vomiting, fatigue, right upper quadrant pain, dark urine, and jaundice.

Perphenazine 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.

Perphenazine 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.

Perphenazine 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.

The phenyltoloxamine in Myophen has a moderate potential interaction with Asthma.

It has been suggested that the anticholinergic effect of antihistamines may reduce the volume and cause thickening of bronchial secretions, resulting in obstruction of respiratory tract. Some manufacturers and clinicians recommend that therapy with antihistamines be administered cautiously in patients with asthma or chronic obstructive pulmonary disease.

Perphenazine 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.

Perphenazine 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.

Perphenazine 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.

The phenyltoloxamine in Myophen has a moderate potential interaction with Cardiovascular Conditions and Disorders.

Antihistamines may infrequently cause cardiovascular adverse effects related to their anticholinergic and local anesthetic (quinidine-like) activities. Tachycardia, palpitation, ECG changes, arrhythmias, hypotension, and hypertension have been reported. Although these effects are uncommon and usually limited to overdosage situations, the manufacturers and some clinicians recommend that therapy with antihistamines be administered cautiously in patients with cardiovascular disease, hypertension, and/or hyperthyroidism.

Perphenazine 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.

Perphenazine 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.

The phenyltoloxamine in Myophen has a moderate potential interaction with COPD.

It has been suggested that the anticholinergic effect of antihistamines may reduce the volume and cause thickening of bronchial secretions, resulting in obstruction of respiratory tract. Some manufacturers and clinicians recommend that therapy with antihistamines be administered cautiously in patients with asthma or chronic obstructive pulmonary disease.

The acetaminophen in Myophen has a major potential interaction with Dehydration.

Acetaminophen is contraindicated in patients with severe hepatic impairment or severe active liver disease. Patients with hepatic impairment may be at increased risk of toxicity. Severe liver injury, including cases of acute liver failure and death, have been reported in patients using this drug. Clinical monitoring of hepatic function is recommended. Caution is advised if using acetaminophen in patients with chronic malnutrition or severe hypovolemia. Instruct patients to avoid drinking alcohol while taking acetaminophen-containing medications. Patients should be warned not to exceed the maximum recommended total daily dosage of acetaminophen (4 g/day in adults and children 12 years of age or older), and to read all prescription and over-the-counter medication labels to ensure they are not taking multiple acetaminophen-containing products, or check with a healthcare professional if they are unsure.

Perphenazine 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.

The phenyltoloxamine in Myophen has a moderate potential interaction with Gastrointestinal Obstruction.

Antihistamines often have anticholinergic activity, to which elderly patients are particularly sensitive. Therapy with antihistamines should be administered cautiously, if at all, 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. Conventional, first-generation antihistamines such as the ethanolamines (bromodiphenhydramine, carbinoxamine, clemastine, dimenhydrinate, diphenhydramine, doxylamine, phenyltoloxamine) tend to exhibit substantial anticholinergic effects. In contrast, the newer, relatively nonsedating antihistamines (e.g., cetirizine, fexofenadine, loratadine) reportedly have low to minimal anticholinergic activity at normally recommended dosages and may be appropriate alternatives.

The phenyltoloxamine in Myophen has a moderate potential interaction with Glaucoma/Intraocular Hypertension.

Antihistamines often have anticholinergic activity, to which elderly patients are particularly sensitive. Therapy with antihistamines should be administered cautiously, if at all, 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. Conventional, first-generation antihistamines such as the ethanolamines (bromodiphenhydramine, carbinoxamine, clemastine, dimenhydrinate, diphenhydramine, doxylamine, phenyltoloxamine) tend to exhibit substantial anticholinergic effects. In contrast, the newer, relatively nonsedating antihistamines (e.g., cetirizine, fexofenadine, loratadine) reportedly have low to minimal anticholinergic activity at normally recommended dosages and may be appropriate alternatives.

Perphenazine has a major potential interaction with Head Injury.

Perphenazine is contraindicated in patients with suspected or established subcortical brain damage, with or without hypothalamic involvement. Perphenazine can interfere with thermoregulatory mechanisms, and a hyperthermic reaction with temperatures in excess of 40C (104F) may occur in such patients, sometimes not until 14 to 16 hours after drug administration.

Perphenazine 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.

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

Perphenazine is contraindicated in patients with suspected or established subcortical brain damage, with or without hypothalamic involvement. Perphenazine can interfere with thermoregulatory mechanisms, and a hyperthermic reaction with temperatures in excess of 40C (104F) may occur in such patients, sometimes not until 14 to 16 hours after drug administration.

Perphenazine 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.

Perphenazine 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.

The phenyltoloxamine in Myophen has a moderate potential interaction with Hyperthyroidism.

Antihistamines may infrequently cause cardiovascular adverse effects related to their anticholinergic and local anesthetic (quinidine-like) activities. Tachycardia, palpitation, ECG changes, arrhythmias, hypotension, and hypertension have been reported. Although these effects are uncommon and usually limited to overdosage situations, the manufacturers and some clinicians recommend that therapy with antihistamines be administered cautiously in patients with cardiovascular disease, hypertension, and/or hyperthyroidism.

Perphenazine 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.

The phenyltoloxamine in Myophen has a moderate potential interaction with Hypotension.

Antihistamines may infrequently cause cardiovascular adverse effects related to their anticholinergic and local anesthetic (quinidine-like) activities. Tachycardia, palpitation, ECG changes, arrhythmias, hypotension, and hypertension have been reported. Although these effects are uncommon and usually limited to overdosage situations, the manufacturers and some clinicians recommend that therapy with antihistamines be administered cautiously in patients with cardiovascular disease, hypertension, and/or hyperthyroidism.

The acetaminophen in Myophen has a major potential interaction with Liver Disease.

Acetaminophen is contraindicated in patients with severe hepatic impairment or severe active liver disease. Patients with hepatic impairment may be at increased risk of toxicity. Severe liver injury, including cases of acute liver failure and death, have been reported in patients using this drug. Clinical monitoring of hepatic function is recommended. Caution is advised if using acetaminophen in patients with chronic malnutrition or severe hypovolemia. Instruct patients to avoid drinking alcohol while taking acetaminophen-containing medications. Patients should be warned not to exceed the maximum recommended total daily dosage of acetaminophen (4 g/day in adults and children 12 years of age or older), and to read all prescription and over-the-counter medication labels to ensure they are not taking multiple acetaminophen-containing products, or check with a healthcare professional if they are unsure.

Perphenazine 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.

Perphenazine has a major potential interaction with Liver Disease.

The manufacturer considers the use of perphenazine to be contraindicated in patients with preexisting liver damage. Phenothiazines are extensively metabolized by the liver and may accumulate in patients with hepatic impairment.

The phenyltoloxamine in Myophen has a moderate potential interaction with Liver Disease.

Limited pharmacokinetic data are available for the older, first-generation antihistamines. Many appear to be primarily metabolized by the liver, and both parent drugs and metabolites are excreted in the urine. Patients with renal and/or liver disease may be at greater risk for adverse effects from antihistamines due to drug and metabolite accumulation. Therapy with antihistamines should be administered cautiously in such patients. Lower initial dosages may be appropriate.

The acetaminophen in Myophen has a major potential interaction with Malnourishment.

Acetaminophen is contraindicated in patients with severe hepatic impairment or severe active liver disease. Patients with hepatic impairment may be at increased risk of toxicity. Severe liver injury, including cases of acute liver failure and death, have been reported in patients using this drug. Clinical monitoring of hepatic function is recommended. Caution is advised if using acetaminophen in patients with chronic malnutrition or severe hypovolemia. Instruct patients to avoid drinking alcohol while taking acetaminophen-containing medications. Patients should be warned not to exceed the maximum recommended total daily dosage of acetaminophen (4 g/day in adults and children 12 years of age or older), and to read all prescription and over-the-counter medication labels to ensure they are not taking multiple acetaminophen-containing products, or check with a healthcare professional if they are unsure.

Perphenazine 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.

The acetaminophen in Myophen has a moderate potential interaction with Phenylketonuria.

Several oral acetaminophen and acetaminophen-combination products, particularly flavored chewable tablets, contain the artificial sweetener, aspartame (NutraSweet). Aspartame is converted to phenylalanine in the gastrointestinal tract following ingestion. Chewable and effervescent formulations of acetaminophen products may also contain phenylalanine. The aspartame/phenylalanine content should be considered when these products are used in patients who must restrict their intake of phenylalanine (i.e. phenylketonurics).

Perphenazine 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.

The phenyltoloxamine in Myophen has a moderate potential interaction with Renal Dysfunction.

Limited pharmacokinetic data are available for the older, first-generation antihistamines. Many appear to be primarily metabolized by the liver, and both parent drugs and metabolites are excreted in the urine. Patients with renal and/or liver disease may be at greater risk for adverse effects from antihistamines due to drug and metabolite accumulation. Therapy with antihistamines should be administered cautiously in such patients. Lower initial dosages may be appropriate.

Perphenazine 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.

Perphenazine 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.

Perphenazine 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.

The phenyltoloxamine in Myophen has a moderate potential interaction with Urinary Retention.

Antihistamines often have anticholinergic activity, to which elderly patients are particularly sensitive. Therapy with antihistamines should be administered cautiously, if at all, 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. Conventional, first-generation antihistamines such as the ethanolamines (bromodiphenhydramine, carbinoxamine, clemastine, dimenhydrinate, diphenhydramine, doxylamine, phenyltoloxamine) tend to exhibit substantial anticholinergic effects. In contrast, the newer, relatively nonsedating antihistamines (e.g., cetirizine, fexofenadine, loratadine) reportedly have low to minimal anticholinergic activity at normally recommended dosages and may be appropriate alternatives.

Perphenazine 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.