About dextromethorphan hydrobromide + quinidine sulfate
Dextromethorphan and quinidine combination
Used for
- Treats pseudobulbar affect: sudden, uncontrollable laughing or crying unrelated to mood.
Usual adult dose
One capsule daily for 7 days, then one capsule every 12 hours.
Common side effects
- Diarrhea
- Dizziness
- Cough
- Vomiting
Important warnings
- Can cause abnormal heart rhythms; avoid with certain heart conditions or prolonged QT interval.
- May cause dizziness and falls, especially in older adults.
- Can cause serotonin syndrome, especially with antidepressants or other serotonergic medicines.
- Quinidine can cause serious allergic reactions or low platelets.
Pregnancy
Human pregnancy information is limited; use only when clearly needed after weighing potential risks.
Breastfeeding
Unknown whether these medicines enter breast milk; effects on a nursing infant are uncertain.
Interactions
- MAO inhibitors: combination is contraindicated.
- Medicines that prolong QT interval can increase abnormal heart rhythm risk.
- Serotonergic medicines can increase serotonin syndrome risk.
- Quinidine raises levels of some medicines, including digoxin and certain CYP2D6 substrates.
AI-generated from general medical knowledge, not from this product's official leaflet. It may be incomplete or out of date. Not medical advice — ask a pharmacist or doctor before making any decision.