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Can you take Ponesimod with Promethazine DM?

2 drug interactions and 47 additional warnings found for the following 2 drugs:

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Drug interactions

Major drug interactions

Major:

promethazine ponesimod

Applies to: Promethazine DM (dextromethorphan / promethazine) and ponesimod

Before starting ponesimod, let your doctor know if you are currently receiving treatment with promethazine. Using ponesimod in this situation can increase the risk of an irregular heart rhythm that may be serious and potentially life-threatening, although it is a relatively rare side effect.

You may also be more susceptible if you have:

  • a heart condition called congenital long QT syndrome
  • other cardiac diseases
  • conduction abnormalities
  • electrolyte disturbances (for example, magnesium or potassium loss due to severe or prolonged diarrhea or vomiting)

Talk to your doctor if you have any questions or concerns.

You should seek immediate medical attention if you develop sudden dizziness, lightheadedness, fainting, shortness of breath, or heart palpitations during treatment with these medications, whether together or alone.

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 drug interactions

Moderate:

dextromethorphan promethazine

Applies to: Promethazine DM (dextromethorphan / promethazine) and Promethazine DM (dextromethorphan / promethazine)

Using dextromethorphan together with promethazine may increase side effects such as:

  • dizziness
  • drowsiness
  • confusion
  • difficulty concentrating

Some people, especially the elderly, may also experience impairment in thinking, judgment, and motor coordination.

What to do: You should avoid or limit the use of alcohol while being treated with these medications. Also avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medications affect you.

Talk to your doctor if you have any questions or concerns. 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:

dextromethorphan Food/Lifestyle

Applies to: Promethazine DM (dextromethorphan / promethazine)

Alcohol can increase the nervous system side effects of dextromethorphan such as:

  • dizziness
  • drowsiness
  • difficulty concentrating

Some people may also experience impairment in thinking and judgment.

You should avoid or limit the use of alcohol while being treated with dextromethorphan.

Do not use more than the recommended dose of dextromethorphan, and avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medication affects you.

Talk to your doctor or pharmacist if you have any questions or concerns.

Moderate:

promethazine Alcohol (Ethanol)

Applies to: Promethazine DM (dextromethorphan / promethazine)

Ask your doctor before using promethazine 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

45 potential interactions Applies to: 38 conditions, including High Blood Pressure, Asthma, COPD, Seizures, and Arrhythmia.

Acute Alcohol Intoxication

Major:

Promethazine DM

The promethazine in Promethazine DM 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:

Promethazine DM

The promethazine in Promethazine DM 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.

Altered Consciousness

Major:

Promethazine DM

The promethazine in Promethazine DM 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:

Promethazine DM

The promethazine in Promethazine DM 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.

Moderate:

ponesimod

Ponesimod has a moderate potential interaction with Arrhythmia.

The use of ponesimod may result in a transient decrease in heart rate and atrioventricular (AV) conduction delays, especially during treatment initiation. This drug is not recommended in patients with a history of cardiac arrest, cerebrovascular disease (e.g., TIA, stroke occurring more than 6 months prior to treatment initiation), uncontrolled hypertension, or severe untreated sleep apnea, since significant bradycardia may be poorly tolerated in these patients. The use of this drug in patients with a history of recurrent syncope or symptomatic bradycardia should be based on an overall benefit-risk assessment. Obtain an ECG in all patients to determine whether preexisting conduction abnormalities are present and consult a cardiologist if appropriate. Monitor closely patients taking concurrent therapy with drugs that decrease heart rate (e.g., beta-blockers, non-dihydropyridine calcium channel blockers, and other drugs that may decrease heart rate).

Asthma

Moderate:

Promethazine DM

The promethazine in Promethazine DM 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.

Bone Marrow Depression/Low Blood Counts

Major:

Promethazine DM

The promethazine in Promethazine DM 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.

Breast Cancer

Moderate:

Promethazine DM

The promethazine in Promethazine DM 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:

Promethazine DM

The promethazine in Promethazine DM 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:

ponesimod

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

Rare cases of posterior reversible encephalopathy syndrome (PRES) have been reported in patients receiving a sphingosine 1-phosphate receptor modulator. It is recommended to promptly schedule a complete physical and neurological examination and should consider an MRI, if a patient develops any unexpected neurological or psychiatric symptoms/signs, any symptom/sign suggestive of an increase of intracranial pressure, or accelerated neurological deterioration. Delay in diagnosis and treatment may lead to permanent neurological sequelae. Exercise care when using this agent in patients with a history of ischemic stroke or cerebral hemorrhage. Treatment should be discontinued if PRES is suspected.

Moderate:

Promethazine DM

The promethazine in Promethazine DM 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:

Promethazine DM

The promethazine in Promethazine DM 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.

COPD

Moderate:

Promethazine DM

The promethazine in Promethazine DM 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.

Dehydration

Major:

Promethazine DM

The promethazine in Promethazine DM has a major potential interaction with Dehydration.

Promethazine has weak central antidopaminergic activity. While its use is rarely associated with adverse effects secondary to dopaminergic blockade, large doses have produced extrapyramidal reactions. During chronic administration and/or high-dose therapy, the usual contraindications, warnings and precautions applicable to phenothiazines should be observed with promethazine.

Diabetes Mellitus

Moderate:

ponesimod

Ponesimod has a moderate potential interaction with Diabetes Mellitus.

Macular edema has been reported with the use of sphingosine 1-phosphate (S1P) receptor modulators. Care should be exercised when using these drugs in patients with a history of uveitis and patients with diabetes mellitus as these patients are at increased risk for macular edema. Before starting treatment with these agents, an ophthalmic evaluation of the fundus, including the macula, is recommended in all patients and at any time if vision change is reported during treatment. Patients with a history of uveitis and patients with diabetes mellitus should have regular follow-up examinations of the fundus, including the macula during treatment. Continuation of therapy in patients with macular edema has not been evaluated, therefore, a decision on whether or not to discontinue treatment needs to take into account the potential benefits and risks for the individual patients.

Gastrointestinal Obstruction

Moderate:

Promethazine DM

The promethazine in Promethazine DM 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.

Glaucoma/Intraocular Hypertension

Moderate:

Promethazine DM

The promethazine in Promethazine DM 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.

Heart Disease

Moderate:

ponesimod

Ponesimod has a moderate potential interaction with Heart Disease.

The use of ponesimod may result in a transient decrease in heart rate and atrioventricular (AV) conduction delays, especially during treatment initiation. This drug is not recommended in patients with a history of cardiac arrest, cerebrovascular disease (e.g., TIA, stroke occurring more than 6 months prior to treatment initiation), uncontrolled hypertension, or severe untreated sleep apnea, since significant bradycardia may be poorly tolerated in these patients. The use of this drug in patients with a history of recurrent syncope or symptomatic bradycardia should be based on an overall benefit-risk assessment. Obtain an ECG in all patients to determine whether preexisting conduction abnormalities are present and consult a cardiologist if appropriate. Monitor closely patients taking concurrent therapy with drugs that decrease heart rate (e.g., beta-blockers, non-dihydropyridine calcium channel blockers, and other drugs that may decrease heart rate).

High Blood Pressure

Major:

Promethazine DM

The promethazine in Promethazine DM 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.

Moderate:

ponesimod

Ponesimod has a moderate potential interaction with High Blood Pressure.

The use of ponesimod may result in a transient decrease in heart rate and atrioventricular (AV) conduction delays, especially during treatment initiation. This drug is not recommended in patients with a history of cardiac arrest, cerebrovascular disease (e.g., TIA, stroke occurring more than 6 months prior to treatment initiation), uncontrolled hypertension, or severe untreated sleep apnea, since significant bradycardia may be poorly tolerated in these patients. The use of this drug in patients with a history of recurrent syncope or symptomatic bradycardia should be based on an overall benefit-risk assessment. Obtain an ECG in all patients to determine whether preexisting conduction abnormalities are present and consult a cardiologist if appropriate. Monitor closely patients taking concurrent therapy with drugs that decrease heart rate (e.g., beta-blockers, non-dihydropyridine calcium channel blockers, and other drugs that may decrease heart rate).

Moderate:

ponesimod

Ponesimod has a moderate potential interaction with High Blood Pressure.

The use of ponesimod may result in increased blood pressure. Care should be exercised when using this drug in hypertensive patients and those at risk for hypertension. It is recommended to monitor blood pressure during treatment and manage it according to clinical practices.

History - Cerebrovascular Disease

Major:

Promethazine DM

The promethazine in Promethazine DM 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:

Promethazine DM

The promethazine in Promethazine DM 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.

Hypocalcemia

Major:

Promethazine DM

The promethazine in Promethazine DM has a major potential interaction with Hypocalcemia.

Promethazine has weak central antidopaminergic activity. While its use is rarely associated with adverse effects secondary to dopaminergic blockade, large doses have produced extrapyramidal reactions. During chronic administration and/or high-dose therapy, the usual contraindications, warnings and precautions applicable to phenothiazines should be observed with promethazine.

Hypotension

Major:

Promethazine DM

The promethazine in Promethazine DM 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.

Infection

Moderate:

ponesimod

Ponesimod has a moderate potential interaction with Infection.

The use of ponesimod may increase the risk of infections, and some serious infections with opportunistic pathogens including viruses have been reported. Prior to treatment, a recent CBC (i.e., within 6 months or after discontinuation of prior therapy) should be available. It is recommended to delay treatment initiation in patients with an active infection until complete resolution. Consider withholding treatment if a patient develops a serious infection, and reassess the benefits and risks prior to reinitiating therapy.

Liver Disease

Major:

Promethazine DM

The promethazine in Promethazine DM 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:

ponesimod

Ponesimod has a moderate potential interaction with Liver Disease.

The use of this drug may increase liver transaminases. Ponesimod is not recommended in patients with moderate or severe hepatic impairment (Child-Pugh class B and C). No dosage adjustment is necessary for patients with mild hepatic impairment (Child-Pugh class A). Patients should have liver enzymes checked if they develop symptoms suggestive of hepatic dysfunction, such as unexplained nausea, vomiting, abdominal pain, fatigue, anorexia, a rash with eosinophilia, or jaundice and/or dark urine during treatment. Obtain transaminase and bilirubin levels, if not recently available (i.e., within the last 6 months) before treatment initiation. Treatment should be discontinued if significant liver injury is confirmed.

Macular Edema

Moderate:

ponesimod

Ponesimod has a moderate potential interaction with Macular Edema.

Macular edema has been reported with the use of sphingosine 1-phosphate (S1P) receptor modulators. Care should be exercised when using these drugs in patients with a history of uveitis and patients with diabetes mellitus as these patients are at increased risk for macular edema. Before starting treatment with these agents, an ophthalmic evaluation of the fundus, including the macula, is recommended in all patients and at any time if vision change is reported during treatment. Patients with a history of uveitis and patients with diabetes mellitus should have regular follow-up examinations of the fundus, including the macula during treatment. Continuation of therapy in patients with macular edema has not been evaluated, therefore, a decision on whether or not to discontinue treatment needs to take into account the potential benefits and risks for the individual patients.

Multiple Sclerosis

Moderate:

ponesimod

Ponesimod has a moderate potential interaction with Multiple Sclerosis.

Rare cases of severe exacerbation of multiple sclerosis (MS), including disease rebound, have been reported after discontinuation of sphingosine 1-phosphate receptor modulator in MS treated patients. The possibility of severe exacerbation of disease should be considered after stopping treatment with these agents. Patients should be observed for a severe increase in disability upon discontinuation and appropriate treatment should be instituted, as required.

Neuroleptic Malignant Syndrome

Major:

Promethazine DM

The promethazine in Promethazine DM has a major potential interaction with Neuroleptic Malignant Syndrome.

Promethazine has weak central antidopaminergic activity. While its use is rarely associated with adverse effects secondary to dopaminergic blockade, large doses have produced extrapyramidal reactions. During chronic administration and/or high-dose therapy, the usual contraindications, warnings and precautions applicable to phenothiazines should be observed with promethazine.

Moderate:

Promethazine DM

The promethazine in Promethazine DM 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.

Parkinsonism

Moderate:

Promethazine DM

The promethazine in Promethazine DM has a moderate potential interaction with Parkinsonism.

Promethazine has weak central antidopaminergic activity. While its use is rarely associated with adverse effects secondary to dopaminergic blockade, large doses have produced extrapyramidal reactions. During chronic administration and/or high-dose therapy, the usual contraindications, warnings and precautions applicable to phenothiazines should be observed with promethazine.

Pheochromocytoma

Major:

Promethazine DM

The promethazine in Promethazine DM 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.

Pulmonary Impairment

Major:

Promethazine DM

The promethazine in Promethazine DM has a major potential interaction with Pulmonary Impairment.

Promethazine is contraindicated for use in the treatment of lower respiratory tract symptoms including asthma. Furthermore, promethazine tablets may lead to potentially fatal respiratory depression, and its use should be avoided in patients with compromised respiratory function such as patients with COPD, and sleep apnea.

Moderate:

ponesimod

Ponesimod has a moderate potential interaction with Pulmonary Impairment.

Dyspnea has been reported with the use of ponesimod. Dose-dependent reductions in forced expiratory volume over 1 second (FEV1) and reductions in diffusion lung capacity for carbon monoxide have been observed in patients mostly occurring in the first month after treatment initiation. Use with caution in patients with severe respiratory disease such as pulmonary fibrosis, asthma, and chronic obstructive pulmonary disease. Spirometric evaluation of respiratory function should be performed during therapy if clinically indicated.

Respiratory Arrest

Major:

Promethazine DM

The promethazine in Promethazine DM 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

Moderate:

Promethazine DM

The promethazine in Promethazine DM 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.

Sleep Apnea

Moderate:

ponesimod

Ponesimod has a moderate potential interaction with Sleep Apnea.

The use of ponesimod may result in a transient decrease in heart rate and atrioventricular (AV) conduction delays, especially during treatment initiation. This drug is not recommended in patients with a history of cardiac arrest, cerebrovascular disease (e.g., TIA, stroke occurring more than 6 months prior to treatment initiation), uncontrolled hypertension, or severe untreated sleep apnea, since significant bradycardia may be poorly tolerated in these patients. The use of this drug in patients with a history of recurrent syncope or symptomatic bradycardia should be based on an overall benefit-risk assessment. Obtain an ECG in all patients to determine whether preexisting conduction abnormalities are present and consult a cardiologist if appropriate. Monitor closely patients taking concurrent therapy with drugs that decrease heart rate (e.g., beta-blockers, non-dihydropyridine calcium channel blockers, and other drugs that may decrease heart rate).

Syncope

Moderate:

ponesimod

Ponesimod has a moderate potential interaction with Syncope.

The use of ponesimod may result in a transient decrease in heart rate and atrioventricular (AV) conduction delays, especially during treatment initiation. This drug is not recommended in patients with a history of cardiac arrest, cerebrovascular disease (e.g., TIA, stroke occurring more than 6 months prior to treatment initiation), uncontrolled hypertension, or severe untreated sleep apnea, since significant bradycardia may be poorly tolerated in these patients. The use of this drug in patients with a history of recurrent syncope or symptomatic bradycardia should be based on an overall benefit-risk assessment. Obtain an ECG in all patients to determine whether preexisting conduction abnormalities are present and consult a cardiologist if appropriate. Monitor closely patients taking concurrent therapy with drugs that decrease heart rate (e.g., beta-blockers, non-dihydropyridine calcium channel blockers, and other drugs that may decrease heart rate).

Tardive Dyskinesia

Major:

Promethazine DM

The promethazine in Promethazine DM has a major potential interaction with Tardive Dyskinesia.

Promethazine has weak central antidopaminergic activity. While its use is rarely associated with adverse effects secondary to dopaminergic blockade, large doses have produced extrapyramidal reactions. During chronic administration and/or high-dose therapy, the usual contraindications, warnings and precautions applicable to phenothiazines should be observed with promethazine.

Urinary Retention

Moderate:

Promethazine DM

The promethazine in Promethazine DM 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.

Uveitis

Moderate:

ponesimod

Ponesimod has a moderate potential interaction with Uveitis.

Macular edema has been reported with the use of sphingosine 1-phosphate (S1P) receptor modulators. Care should be exercised when using these drugs in patients with a history of uveitis and patients with diabetes mellitus as these patients are at increased risk for macular edema. Before starting treatment with these agents, an ophthalmic evaluation of the fundus, including the macula, is recommended in all patients and at any time if vision change is reported during treatment. Patients with a history of uveitis and patients with diabetes mellitus should have regular follow-up examinations of the fundus, including the macula during treatment. Continuation of therapy in patients with macular edema has not been evaluated, therefore, a decision on whether or not to discontinue treatment needs to take into account the potential benefits and risks for the individual patients.

Vaccination

Moderate:

ponesimod

Ponesimod has a moderate potential interaction with Vaccination.

The use of live attenuated vaccines should be avoided while patients are taking ponesimod and for 1 to 2 weeks after stopping treatment. Patients without a healthcare professional documented history of chickenpox or documentation of a full course of vaccination against varicella zoster virus (VZV) should be tested for antibodies to VZV before the start of treatment. A full course of vaccination for antibody-negative patients with varicella vaccine is recommended prior to treatment initiation. Vaccinations may be less effective if administered during treatment and for up to 1 to 2 weeks after treatment discontinuation. It is recommended to postpone treatment with ponesimod for 4 weeks to allow the full effect of vaccination to occur. If live attenuated vaccine immunizations are required, administer at least 1 month prior to initiation of treatment.

Valvular Heart Disease

Major:

Promethazine DM

The promethazine in Promethazine DM 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

ponesimod

A total of 725 drugs are known to interact with ponesimod.

Promethazine DM

A total of 773 drugs are known to interact with Promethazine DM.

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.