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Drug Interaction Report

2 drug interactions and 28 additional warnings found for the following 2 drugs:

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Drug interactions

Moderate drug interactions

Moderate:

cimetidine dextromethorphan

Applies to: cimetidine, Tussar DM (chlorpheniramine / dextromethorphan / phenylephrine)

Cimetidine may increase the blood levels and effects of dextromethorphan.

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 such as:

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:

chlorpheniramine dextromethorphan

Applies to: Tussar DM (chlorpheniramine / dextromethorphan / phenylephrine), Tussar DM (chlorpheniramine / dextromethorphan / phenylephrine)

Using chlorpheniramine together with dextromethorphan 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:

Caffeine phenylephrine

Applies to: Tussar DM (chlorpheniramine / dextromethorphan / phenylephrine)

Both phenylephrine 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.

Moderate:

Food/Lifestyle chlorpheniramine

Applies to: Tussar DM (chlorpheniramine / dextromethorphan / phenylephrine)

Alcohol can increase the nervous system side effects of chlorpheniramine 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 chlorpheniramine.

Do not use more than the recommended dose of chlorpheniramine, 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:

Food/Lifestyle dextromethorphan

Applies to: Tussar DM (chlorpheniramine / dextromethorphan / phenylephrine)

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.

Minor food/lifestyle interactions

Minor:

Alcohol (Ethanol) cimetidine

Applies to: cimetidine

Information for this minor interaction is available on the professional version.

Minor:

Caffeine cimetidine

Applies to: cimetidine

Information for this minor interaction is available on the professional version.

Minor:

Nicotine cimetidine

Applies to: cimetidine

Information for this minor interaction is available on the professional version.

Disease interactions

22 potential interactionsApplies to: 17 conditions, including Asthma, Benign Prostatic Hyperplasia, COPD, Hypotension, and Hyperthyroidism.

Asthma

Moderate:

Tussar DM

The chlorpheniramine in Tussar 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.

Benign Prostatic Hyperplasia

Moderate:

Tussar DM

The phenylephrine in Tussar DM 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:

Tussar DM

The phenylephrine in Tussar DM 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.

Moderate:

Tussar DM

The chlorpheniramine in Tussar DM 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.

Cerebrovascular Insufficiency

Major:

Tussar DM

The phenylephrine in Tussar DM 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.

COPD

Moderate:

Tussar DM

The chlorpheniramine in Tussar 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.

Diabetes Mellitus

Moderate:

Tussar DM

The phenylephrine in Tussar DM 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.

Gastrointestinal Hemorrhage

Major:

cimetidine

Cimetidine has a major potential interaction with Gastrointestinal Hemorrhage.

Histamine H2 receptor antagonists should not be used in the presence of vomit with blood, or bloody or black stools. These might be serious conditions and the diagnosis needs to be ruled out.

Gastrointestinal Obstruction

Moderate:

Tussar DM

The chlorpheniramine in Tussar 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:

Tussar DM

The phenylephrine in Tussar DM has a moderate potential interaction with Glaucoma/Intraocular Hypertension.

Sympathomimetic agents can induce transient mydriasis via stimulation of alpha-1 adrenergic receptors. In patients with anatomically narrow angles or narrow-angle glaucoma, pupillary dilation can provoke an acute attack. In patients with other forms of glaucoma, mydriasis may occasionally increase intraocular pressure. Therapy with sympathomimetic agents should be administered cautiously in patients with or predisposed to glaucoma, particularly narrow-angle glaucoma.

Moderate:

Tussar DM

The chlorpheniramine in Tussar 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.

Hemodialysis

Moderate:

cimetidine

Cimetidine has a moderate potential interaction with Hemodialysis.

Cimetidine is partially removed by hemodialysis and should be administered after dialysis.

Hyperthyroidism

Major:

Tussar DM

The phenylephrine in Tussar DM 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.

Moderate:

Tussar DM

The chlorpheniramine in Tussar DM 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.

Hypotension

Moderate:

Tussar DM

The chlorpheniramine in Tussar DM 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.

Liver Disease

Major:

cimetidine

Cimetidine has a major potential interaction with Liver Disease.

Cimetidine is partially metabolized by the liver, and to a greater extent when administered orally than when given intravenously. Although dosage reductions are generally not necessary, therapy with cimetidine should be administered cautiously in patients with liver disease. Hepatotoxicity has been associated with cimetidine use. In addition, liver disease appears to be a risk factor for cimetidine-related central nervous system toxicity, which may include mental confusion, agitation, psychosis, depression, anxiety, hallucinations, and disorientation. These effects are usually reversible within 3 to 4 days after discontinuation of therapy.

Moderate:

Tussar DM

The chlorpheniramine in Tussar DM 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.

Pheochromocytoma

Major:

Tussar DM

The phenylephrine in Tussar DM 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:

Tussar DM

The phenylephrine in Tussar DM 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.

Renal Dysfunction

Moderate:

cimetidine

Cimetidine has a moderate potential interaction with Renal Dysfunction.

Cimetidine and its metabolites are primarily eliminated by the kidney. The daily dosage should initially be reduced in patients with moderate to severe renal impairment (CrCl < 50 mL/min). If necessary, the daily dosage may be increased with caution. Renal dysfunction also appears to be a risk factor for cimetidine-related central nervous system toxicity, which may include mental confusion, agitation, psychosis, depression, anxiety, hallucinations, and disorientation. These effects are generally reversible within 3 to 4 days after discontinuation of therapy.

Moderate:

Tussar DM

The chlorpheniramine in Tussar DM 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.

Urinary Retention

Moderate:

Tussar DM

The chlorpheniramine in Tussar 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.

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.

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Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.