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Can you take Fenfluramine with Primatene?

1 drug interaction and 24 additional warnings found for the following 2 drugs:

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Drug interactions

Moderate drug interactions

Moderate:

ePHEDrine fenfluramine

Applies to: Primatene (ephedrine / guaifenesin) and fenfluramine

Both ePHEDrine and fenfluramine can increase blood pressure and heart rate, and combining them may enhance these effects.

Talk to your doctor before using these medications, especially if you have a history of high blood pressure or heart disease. You may need a dose adjustment or more frequent monitoring by your doctor to safely use both medications.

Contact your doctor if your condition changes or you experience increased side effects.

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:

fenfluramine Food/Lifestyle

Applies to: fenfluramine

Using fenfluramine with alcohol can increase the risk of cardiovascular side effects such as:

  • increased heart rate
  • chest pain
  • blood pressure changes

In addition, you may also be more likely to experience nervous system side effects such as:

  • dizziness
  • drowsiness
  • depression
  • difficulty concentrating

You should avoid or limit the use of alcohol while being treated with fenfluramine. Do not use more than the recommended dose of fenfluramine, and avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medication affects you.

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

Moderate:

ePHEDrine Caffeine

Applies to: Primatene (ephedrine / guaifenesin)

Both ePHEDrine and caffeine can increase blood pressure and heart rate, and combining them may enhance these effects.

Talk to your doctor before using these medications, especially if you have a history of high blood pressure or heart disease. You may need a dose adjustment or more frequent monitoring by your doctor to safely use both medications.

Contact your doctor if your condition changes or you experience increased side effects.

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

22 potential interactions Applies to: 19 conditions, including High Blood Pressure, Depression, Benign Prostatic Hyperplasia, Hyperthyroidism, and Pulmonary Arterial Hypertension.

Alcoholism

Moderate:

fenfluramine

Fenfluramine has a moderate potential interaction with Alcoholism.

Fenfluramine can cause somnolence, sedation, and lethargy. Central nervous system depressants, including alcohol, could potentiate these effects. Exercise caution when using this agent in alcoholic patients or those at risk of sedation. Close monitoring is advised. Advise patients not to drive or operate machinery until they know how this drug will affect them.

Benign Prostatic Hyperplasia

Moderate:

Primatene

The ePHEDrine in Primatene has a moderate potential interaction with Benign Prostatic Hyperplasia.

Sympathomimetic agents may cause or worsen urinary difficulty in patients with prostate enlargement due to smooth muscle contraction in the bladder neck via stimulation of alpha-1 adrenergic receptors. Therapy with sympathomimetic agents should be administered cautiously in patients with hypertrophy or neoplasm of the prostate.

Cardiovascular Conditions and Disorders

Major:

Primatene

The ePHEDrine in Primatene has a major potential interaction with Cardiovascular Conditions and Disorders.

Sympathomimetic agents may cause adverse cardiovascular effects, particularly when used in high dosages and/or in susceptible patients. In cardiac tissues, these agents may produce positive chronotropic and inotropic effects via stimulation of beta- 1 adrenergic receptors. Cardiac output, oxygen consumption, and the work of the heart may be increased. In the peripheral vasculature, vasoconstriction may occur via stimulation of alpha-1 adrenergic receptors. Palpitations, tachycardia, arrhythmia, hypertension, reflex bradycardia, coronary occlusion, cerebral vasculitis, myocardial infarction, cardiac arrest, and death have been reported. Some of these agents, particularly ephedra alkaloids (ephedrine, ma huang, phenylpropanolamine), may also predispose patients to hemorrhagic and ischemic stroke. Therapy with sympathomimetic agents should generally be avoided or administered cautiously in patients with sensitivity to sympathomimetic amines, hyperthyroidism, or underlying cardiovascular or cerebrovascular disorders. These agents should not be used in patients with severe coronary artery disease or severe/uncontrolled hypertension.

Cerebrovascular Insufficiency

Major:

Primatene

The ePHEDrine in Primatene has a major potential interaction with Cerebrovascular Insufficiency.

Sympathomimetic agents may cause adverse cardiovascular effects, particularly when used in high dosages and/or in susceptible patients. In cardiac tissues, these agents may produce positive chronotropic and inotropic effects via stimulation of beta- 1 adrenergic receptors. Cardiac output, oxygen consumption, and the work of the heart may be increased. In the peripheral vasculature, vasoconstriction may occur via stimulation of alpha-1 adrenergic receptors. Palpitations, tachycardia, arrhythmia, hypertension, reflex bradycardia, coronary occlusion, cerebral vasculitis, myocardial infarction, cardiac arrest, and death have been reported. Some of these agents, particularly ephedra alkaloids (ephedrine, ma huang, phenylpropanolamine), may also predispose patients to hemorrhagic and ischemic stroke. Therapy with sympathomimetic agents should generally be avoided or administered cautiously in patients with sensitivity to sympathomimetic amines, hyperthyroidism, or underlying cardiovascular or cerebrovascular disorders. These agents should not be used in patients with severe coronary artery disease or severe/uncontrolled hypertension.

Depression

Major:

fenfluramine

Fenfluramine 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.

Moderate:

fenfluramine

Fenfluramine has a moderate potential interaction with Depression.

Antiepileptic drugs (AEDs) have been associated with an increased risk of suicidal thoughts or behavior in patients taking these drugs for any indication. Pooled analyses of 199 placebo-controlled clinical studies involving the use of 11 different AEDs showed that patients receiving AEDs had approximately twice the risk of suicidal thinking or behavior compared to patients receiving placebo. AEDs should be administered cautiously in patients with depression or other psychiatric disorders; phentermine-topiramate should be avoided in patients with history of suicidal attempts or active suicidal ideation. The risk of suicidal thoughts and behavior should be carefully assessed against the risk of untreated illness, bearing in mind that epilepsy and many other conditions for which AEDs are prescribed are themselves associated with morbidity and mortality and an increased risk of suicidal thoughts and behavior. Patients, caregivers, and families should be alert to the emergence or worsening of signs and symptoms of depression, any unusual changes in mood or behavior, or the emergence of suicidal thoughts or behavior. If patients have symptoms of suicidal ideation or behavior, a dosage reduction or treatment discontinuation should be considered.

Diabetes Mellitus

Moderate:

Primatene

The ePHEDrine in Primatene has a moderate potential interaction with Diabetes Mellitus.

Sympathomimetic agents may cause increases in blood glucose concentrations. These effects are usually transient and slight but may be significant with dosages higher than those normally recommended. Therapy with sympathomimetic agents should be administered cautiously in patients with diabetes mellitus. Closer monitoring of blood glucose concentrations may be appropriate.

Moderate:

Primatene

The ePHEDrine in Primatene has a moderate potential interaction with Diabetes Mellitus.

Ephedrine may produce slight increases in blood glucose concentrations. Therapy with ephedrine should be administered cautiously in patients with diabetes mellitus. Closer monitoring of blood glucose concentrations may be appropriate. It is important that the recommended dosages of ephedrine are not exceeded.

Failure to Thrive

Moderate:

fenfluramine

Fenfluramine has a moderate potential interaction with Failure to Thrive.

Fenfluramine can cause decreases in appetite and weight. Exercise care when using this agent in patients at risk of decreased appetite or weight. It is recommended to monitor the growth of pediatric patients carefully. Weight should be monitored regularly during treatment, and dose modifications should be considered if a decrease in weight is observed.

High Blood Pressure

Moderate:

fenfluramine

Fenfluramine has a moderate potential interaction with High Blood Pressure.

Fenfluramine can cause an increase in blood pressure. Exercise care when using this agent in hypertensive patients. It is recommended to monitor blood pressure in patients treated with fenfluramine.

Hyperthyroidism

Major:

Primatene

The ePHEDrine in Primatene has a major potential interaction with Hyperthyroidism.

Sympathomimetic agents may cause adverse cardiovascular effects, particularly when used in high dosages and/or in susceptible patients. In cardiac tissues, these agents may produce positive chronotropic and inotropic effects via stimulation of beta- 1 adrenergic receptors. Cardiac output, oxygen consumption, and the work of the heart may be increased. In the peripheral vasculature, vasoconstriction may occur via stimulation of alpha-1 adrenergic receptors. Palpitations, tachycardia, arrhythmia, hypertension, reflex bradycardia, coronary occlusion, cerebral vasculitis, myocardial infarction, cardiac arrest, and death have been reported. Some of these agents, particularly ephedra alkaloids (ephedrine, ma huang, phenylpropanolamine), may also predispose patients to hemorrhagic and ischemic stroke. Therapy with sympathomimetic agents should generally be avoided or administered cautiously in patients with sensitivity to sympathomimetic amines, hyperthyroidism, or underlying cardiovascular or cerebrovascular disorders. These agents should not be used in patients with severe coronary artery disease or severe/uncontrolled hypertension.

Liver Disease

Moderate:

fenfluramine

Fenfluramine has a moderate potential interaction with Liver Disease.

Fenfluramine is primarily metabolized to norfenfluramine in the liver. The maximum daily dosage of 20 mg per day should not be exceeded in patients with mild and moderate liver dysfunction. Patients with severe liver dysfunction should not exceed 17 mg per day. The manufacturer prescribing information should be consulted for dose adjustment information of fenfluramine with other concomitant antiepileptic drugs.

Malnourishment

Moderate:

fenfluramine

Fenfluramine has a moderate potential interaction with Malnourishment.

Fenfluramine can cause decreases in appetite and weight. Exercise care when using this agent in patients at risk of decreased appetite or weight. It is recommended to monitor the growth of pediatric patients carefully. Weight should be monitored regularly during treatment, and dose modifications should be considered if a decrease in weight is observed.

Pheochromocytoma

Major:

Primatene

The ePHEDrine in Primatene has a major potential interaction with Pheochromocytoma.

Sympathomimetic agents may cause adverse cardiovascular effects, particularly when used in high dosages and/or in susceptible patients. In cardiac tissues, these agents may produce positive chronotropic and inotropic effects via stimulation of beta- 1 adrenergic receptors. Cardiac output, oxygen consumption, and the work of the heart may be increased. In the peripheral vasculature, vasoconstriction may occur via stimulation of alpha-1 adrenergic receptors. Palpitations, tachycardia, arrhythmia, hypertension, reflex bradycardia, coronary occlusion, cerebral vasculitis, myocardial infarction, cardiac arrest, and death have been reported. Some of these agents, particularly ephedra alkaloids (ephedrine, ma huang, phenylpropanolamine), may also predispose patients to hemorrhagic and ischemic stroke. Therapy with sympathomimetic agents should generally be avoided or administered cautiously in patients with sensitivity to sympathomimetic amines, hyperthyroidism, or underlying cardiovascular or cerebrovascular disorders. These agents should not be used in patients with severe coronary artery disease or severe/uncontrolled hypertension.

Prostate Tumor, Benign

Moderate:

Primatene

The ePHEDrine in Primatene has a moderate potential interaction with Prostate Tumor, Benign.

Sympathomimetic agents may cause or worsen urinary difficulty in patients with prostate enlargement due to smooth muscle contraction in the bladder neck via stimulation of alpha-1 adrenergic receptors. Therapy with sympathomimetic agents should be administered cautiously in patients with hypertrophy or neoplasm of the prostate.

Psychosis

Major:

fenfluramine

Fenfluramine 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.

Moderate:

fenfluramine

Fenfluramine has a moderate potential interaction with Psychosis.

Antiepileptic drugs (AEDs) have been associated with an increased risk of suicidal thoughts or behavior in patients taking these drugs for any indication. Pooled analyses of 199 placebo-controlled clinical studies involving the use of 11 different AEDs showed that patients receiving AEDs had approximately twice the risk of suicidal thinking or behavior compared to patients receiving placebo. AEDs should be administered cautiously in patients with depression or other psychiatric disorders; phentermine-topiramate should be avoided in patients with history of suicidal attempts or active suicidal ideation. The risk of suicidal thoughts and behavior should be carefully assessed against the risk of untreated illness, bearing in mind that epilepsy and many other conditions for which AEDs are prescribed are themselves associated with morbidity and mortality and an increased risk of suicidal thoughts and behavior. Patients, caregivers, and families should be alert to the emergence or worsening of signs and symptoms of depression, any unusual changes in mood or behavior, or the emergence of suicidal thoughts or behavior. If patients have symptoms of suicidal ideation or behavior, a dosage reduction or treatment discontinuation should be considered.

Pulmonary Arterial Hypertension

Major:

fenfluramine

Fenfluramine has a major potential interaction with Pulmonary Arterial Hypertension.

Serotonergic drugs with 5-HT2B receptor agonist activity, including fenfluramine, have been associated with pulmonary arterial hypertension. Exercise care when using this agent in patients with pulmonary disease. Cardiac monitoring is required before starting, during, and after treatment. Cardiac monitoring via echocardiogram can identify evidence of pulmonary arterial hypertension. If pulmonary arterial hypertension is observed on an echocardiogram, the prescriber must consider the benefits versus the risks of initiating or continuing treatment. Echocardiograms should be repeated every six months, and once 3-6 months posttreatment.

Renal Dysfunction

Moderate:

fenfluramine

Fenfluramine has a moderate potential interaction with Renal Dysfunction.

Fenfluramine has not been studied in patients with end-stage renal disease (eGFR less than 15 mL/min/1.73 m2). In patients with severe renal dysfunction (eGFR 15 to 29 mL/min/1.73 m2) the maximum daily dosage of 20 mg per day should not be exceeded (17 mg per day if concomitant stiripentol is used). No dose adjustments are required for patients with mild and moderate renal dysfunction.

Urinary Tract Obstruction

Moderate:

Primatene

The ePHEDrine in Primatene has a moderate potential interaction with Urinary Tract Obstruction.

Sympathomimetic agents such as ephedrine have the potential for producing clinically significant systemic effects, particularly during prolonged or indiscriminate use. In patients with prostate enlargement, urinary difficulty may develop or worsen due to smooth muscle contraction in the bladder neck via stimulation of alpha-1 adrenergic receptors. Therapy with ephedrine should be administered cautiously in patients with difficulty for urination due to hypertrophy or neoplasm of the prostate. It is important that the recommended dosages are not exceeded.

Valvular Heart Disease

Major:

fenfluramine

Fenfluramine has a major potential interaction with Valvular Heart Disease.

Serotonergic drugs with 5-HT2B receptor agonist activity, including fenfluramine have been associated with valvular heart disease. Exercise care when using this agent in patients with cardiac disease. Cardiac monitoring is required prior to starting, during, and after treatment. If valvular heart disease is observed on an echocardiogram, the prescriber must consider the benefits versus the risks of initiating or continuing treatment. Echocardiograms should be repeated every six months, and once 3-6 months posttreatment.

Visual Defect/Disturbance

Moderate:

fenfluramine

Fenfluramine has a moderate potential interaction with Visual Defect/Disturbance.

Fenfluramine can cause mydriasis and can precipitate angle-closure glaucoma. Exercise care when using this agent in patients with visual disturbances. Consider discontinuing treatment in patients with acute decrease in visual acuity or ocular pain.

More resources

fenfluramine

A total of 850 drugs are known to interact with fenfluramine.

Primatene

A total of 243 drugs are known to interact with Primatene.

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.