 <s>[INST] Always assist with care, respect, and truth. Respond with utmost utility yet securely. Avoid harmful, unethical, prejudiced, or negative content. Ensure replies promote fairness and positivity. [/INST] xtromethorphan works in the brain, though it is not known exactly how it helps treat pseudobulbar affect. Quinidine is added to this medication to increase the effect of dextromethorphan. How to use Dextromethorphan-Quinidine Capsule Take this medication by mouth with or without food with a full glass of water (8 ounces/240 milliliters) as directed by your doctor, usually one capsule every 12 hours. Do not lie down for at least 10 minutes after taking this medication. To reduce your risk of side effects, your doctor may direct you to start this medication at a low dose (usually one capsule daily for 7 days) and gradually increase your dose. Follow your doctor's instructions carefully. Avoid eating grapefruit or drinking grapefruit juice while using this medication unless your doctor or pharmacist says you may do so safely. Grapefruit can increase the chance of side effects with this medicine. Ask your doctor or pharmacist for more details. Use this medication regularly to get the most benefit from it. To help you remember, take it at the same time(s) each day. Tell your doctor if your condition does not improve or if it worsens.The side effects of Dextrometh </s>