D%252525252520cold

# Dextromethorphan (DM) ## Overview Dextromethorphan is a synthetic levorphanol derivative that acts as a centrally acting cough suppressant. It elevates the cough threshold in the medulla oblongata. It possesses no significant analgesic or addictive properties at therapeutic doses. ## Primary Indications Temporary relief of non-productive cough caused by minor throat and bronchial irritation (e.g., common cold, inhaled irritants). ## Adult Dosing * **Immediate-release:** 10–20 mg every 4 hours OR 30 mg every 6–8 hours. * **Extended-release:** 60 mg twice daily. * **Maximum Dosage:** 120 mg per 24 hours. ## Pediatric Dosing * **Children 6 to 12 years:** 5–10 mg every 4 hours OR 15 mg every 6–8 hours. Maximum: 60 mg/24 hours. * **Children 4 to 6 years:** 2.5–5 mg every 4 hours OR 7.5 mg every 6–8 hours. Maximum: 30 mg/24 hours. * **Under 4 years:** Generally not recommended due to lack of efficacy and safety concerns; use only under direct medical supervision per local pediatric protocol. ## Dose Adjustments * **Hepatic Impairment:** Reduce dose or increase dosing interval in severe hepatic impairment, as DM is extensively metabolized by CYP2D6. * **Renal Impairment:** No specific adjustment required, but use with caution. ## Contraindications * Hypersensitivity to dextromethorphan. * Concurrent use or within 14 days of Monoamine Oxidase Inhibitors (MAOIs). * Presence of chronic or persistent cough (e.g., caused by asthma, emphysema, or smoking). ## Adverse Effects * **Common:** Dizziness, lightheadedness, nausea, vomiting, stomach pain. * **Severe:** Serotonin syndrome (at high doses or with serotonergic drugs), euphoria, hallucinations, confusion, and respiratory depression (rare). ## Key Drug Interactions * **MAOIs:** Risk of hypertensive crisis, hyperpyrexia, and serotonin syndrome. * **SSRIs/SNRIs/TCAs:** Increased risk of serotonin syndrome due to synergistic serotonergic effects. * **CNS Depressants:** Alcohol, sedatives, or antihistamines may potentiate sedation. * **CYP2D6 Inhibitors:** (e.g., fluoxetine, paroxetine, quinidine) May significantly increase plasma concentrations of DM. ## Monitoring * Monitor for symptom improvement (cough reduction). * Assess for adverse CNS effects or misuse/abuse. * If cough persists for >7 days or is accompanied by high fever, rash, or persistent headache, discontinue and evaluate for secondary causes. ## Clinical Pearls * Dextromethorphan is frequently combined with other OTC agents (guaifenesin, antihistamines, acetaminophen); always review total patient intake to avoid accidental toxicity or overdose of combination products. * Avoid in patients with productive cough, as suppressing the cough reflex may lead to mucus accumulation and airway obstruction. *** *Disclaimer: This information is for educational purposes and does not replace professional medical judgment. Always verify current prescribing information, institutional protocols, and patient-specific factors before administration.*