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Drug interactions between codeine / dexbrompheniramine / pseudoephedrine and Theraflu Thin Strips Cough

Results for the following 2 drugs:
Theraflu Thin Strips Cough (dextromethorphan)

Interactions between your drugs


codeine dextromethorphan

Applies to: codeine / dexbrompheniramine / pseudoephedrine and Theraflu Thin Strips Cough (dextromethorphan)

Consumer information for this interaction is not currently available.

MONITOR: Opioids may potentiate the effects of serotonergic agents and increase the risk of serotonin syndrome. The interaction has primarily been reported with the phenylpiperidine opioids (e.g., meperidine, fentanyl) and tramadol, which are known to possess some serotonergic activity, although a few cases have involved other opioids such as oxycodone, methadone, morphine, hydromorphone, codeine, and buprenorphine. Serotonin syndrome is a rare but serious and potentially fatal condition thought to result from hyperstimulation of brainstem 5-HT1A and 2A receptors. Symptoms of the serotonin syndrome may include mental status changes such as irritability, altered consciousness, confusion, hallucinations, and coma; autonomic dysfunction such as tachycardia, hyperthermia, diaphoresis, shivering, blood pressure lability, and mydriasis; neuromuscular abnormalities such as hyperreflexia, myoclonus, tremor, rigidity, and ataxia; and gastrointestinal symptoms such as abdominal cramping, nausea, vomiting, and diarrhea. Since many serotonergic agents can also cause central nervous system depression, concomitant use with opioids may result in increased sedation and impairment of judgment, thinking, and psychomotor skills.

MANAGEMENT: Caution is advised when opioids are used concomitantly with serotonergic agents such as selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), monoamine oxidase inhibitors (MAOIs), tricyclic antidepressants (TCAs), other antidepressants/psychotropic agents (e.g., amoxapine, buspirone, lithium, maprotiline, mirtazepine, nefazodone, trazodone, vilazodone), 5-HT1 receptor agonists (triptans), 5-HT3 receptor antagonists, cyclobenzaprine, dextromethorphan, 5-hydroxytryptophan, and St. John's wort. Patients should be monitored for symptoms of the serotonin syndrome during treatment. Particular caution is advised when increasing the dosages of these agents. If serotonin syndrome develops or is suspected during the course of therapy, all serotonergic agents should be discontinued immediately and supportive care rendered as necessary. Moderately ill patients may also benefit from the administration of a serotonin antagonist (e.g., cyproheptadine, chlorpromazine). Severe cases should be managed under consultation with a toxicologist and may require sedation, neuromuscular paralysis, intubation, and mechanical ventilation in addition to the other measures. Patients should also be advised of potentially additive central nervous system effects from these agents and to avoid hazardous activities requiring complete mental alertness and motor coordination until they know how these agents affect them.


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dextromethorphan dexbrompheniramine

Applies to: Theraflu Thin Strips Cough (dextromethorphan) and codeine / dexbrompheniramine / pseudoephedrine

Using dextromethorphan together with dexbrompheniramine may increase side effects such as dizziness, drowsiness, confusion, and difficulty concentrating. Some people, especially the elderly, may also experience impairment in thinking, judgment, and motor coordination. 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.

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Drug and food interactions


dexbrompheniramine food

Applies to: codeine / dexbrompheniramine / pseudoephedrine

Alcohol can increase the nervous system side effects of dexbrompheniramine such as dizziness, drowsiness, and 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 dexbrompheniramine. Do not use more than the recommended dose of dexbrompheniramine, 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.

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Therapeutic duplication warnings

No warnings were found for your selected drugs.

Therapeutic duplication warnings are only returned when drugs within the same group exceed the recommended therapeutic duplication maximum.

Drug Interaction Classification

The classifications below are a guideline only. The relevance of a particular drug interaction to a specific patient is difficult to determine using this tool alone given the large number of variables that may apply.
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 information available.

Do not stop taking any medications without consulting your healthcare provider.

Further information

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