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Can you take Lasmiditan with Promethazine DM?

3 drug interactions and 37 additional warnings found for the following 2 drugs:

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Drug interactions

Major drug interactions

Major:

dextromethorphan lasmiditan

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

Using dextromethorphan together with lasmiditan can increase the risk of a rare but serious condition called serotonin syndrome, which may include symptoms such as:

  • confusion
  • hallucination
  • seizure
  • extreme changes in blood pressure
  • increased heart rate
  • fever
  • excessive sweating
  • shivering or shaking
  • blurred vision
  • muscle spasm or stiffness
  • tremor
  • incoordination
  • stomach cramp
  • nausea
  • vomiting
  • diarrhea

Severe cases may result in coma and even death.

You should seek immediate medical attention if you experience these symptoms while taking the medications.

Talk to your doctor if you have any questions or concerns. Your doctor may already be aware of the risks but has determined that this is the best course of treatment for you and has taken appropriate precautions and is monitoring you closely for any potential complications.

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.

Moderate:

promethazine lasmiditan

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

Lasmiditan may cause sedation, dizziness, and impaired driving ability. The risk and/or severity may be increased when combined with alcohol or other medications that can also cause sedation.

Let your doctor know prior to receiving lasmiditan if you are currently using alcohol or receiving treatment with promethazine, as you may be more likely to experience sedation-related side effects.

Tell your healthcare provider right away if you feel like you cannot stay awake during the time you are normally awake or if you feel like you are going to pass out. Your healthcare provider may lower your dose or stop the medication until your symptoms go away.

Do not drive, operate machinery, or engage in potentially hazardous activities requiring mental alertness and motor coordination until the sedative effects have gone away and you know how these medications affect you.

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

35 potential interactions Applies to: 30 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.

Moderate:

lasmiditan

Lasmiditan has a moderate potential interaction with Alcoholism.

The use of lasmiditan may cause central nervous system (CNS) depression, including dizziness and sedation. Because of the potential for lasmiditan to cause sedation, other cognitive or neuropsychiatric adverse reactions, and driving impairment, this agent should be used with caution if used in combination with alcohol or other CNS depressants. It is recommended to evaluate patients for risk of CNS depression and patients should be warned against engaging in potentially hazardous activities requiring complete mental alertness, such as driving a motor vehicle or operating machinery, for at least 8 hours after lasmiditan is taken. Patients who cannot follow this recommendation should not take lasmiditan.

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.

Moderate:

lasmiditan

Lasmiditan has a moderate potential interaction with Altered Consciousness.

The use of lasmiditan may cause central nervous system (CNS) depression, including dizziness and sedation. Because of the potential for lasmiditan to cause sedation, other cognitive or neuropsychiatric adverse reactions, and driving impairment, this agent should be used with caution if used in combination with alcohol or other CNS depressants. It is recommended to evaluate patients for risk of CNS depression and patients should be warned against engaging in potentially hazardous activities requiring complete mental alertness, such as driving a motor vehicle or operating machinery, for at least 8 hours after lasmiditan is taken. Patients who cannot follow this recommendation should not take lasmiditan.

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.

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:

lasmiditan

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

The use of lasmiditan has been associated with reactions consistent with serotonin syndrome. Serotonin syndrome may also occur with lasmiditan during coadministration with serotonergic drugs. The onset of symptoms usually occurs within minutes to hours of receiving a new or a greater dose of a serotonergic medication. It is recommended to discontinue therapy if serotonin syndrome 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.

Drug Dependence

Moderate:

lasmiditan

Lasmiditan has a moderate potential interaction with Drug Dependence.

The use of lasmiditan has the potential to cause abuse. It is recommended to evaluate patients for risk of drug abuse and observe them for signs of lasmiditan misuse or abuse. Drug dependence was not observed in healthy subjects following abrupt cessation after 7 daily doses of lasmiditan 200 mg or 400 mg.

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.

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.

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.

Liver Disease

Major:

lasmiditan

Lasmiditan has a major potential interaction with Liver Disease.

The use of lasmiditan is not recommended in patients with severe hepatic impairment. No dosage adjustment is needed for patients with mild or moderate hepatic impairment.

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.

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.

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.

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.

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

lasmiditan

A total of 463 drugs are known to interact with lasmiditan.

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.