The need-to-know information for Dextromethorphan


Pearls and Fun Nuggets

1. Medication for the Joker?ūüė¨ In 2010, the FDA approved the combination drug dextromethorphan/quinidine¬†for the treatment of¬†pseudobulbar affect¬†(uncontrollable laughing/crying).

2. If you take too much, you’ll see things ūüĎÄ At doses much higher than medically recommended, DXM and its major metabolite, dextrorphan, acts as an¬†NMDA receptor antagonist, which produces dissociative¬†hallucinogenic¬†states somewhat similar to¬†ketamine¬†and¬†phencyclidine.[46]

3. Be careful when taking it with grapefruit ūüćáCaution should be exercised when taking dextromethorphan when drinking grapefruit¬†juice or eating grapefruits, as¬†compounds in grapefruit affect a number of drugs, including dextromethorphan, through the inhibition of the cytochrome p450 system in the liver, and can lead to excessive accumulation and prolonged effects.¬†

4. It’s related to Morphine ūüíČ It is in the morphinan¬†class of medications with¬†sedative,¬†dissociative, and¬†stimulant¬†properties (at lower doses). In its pure form, dextromethorphan occurs as a white powder.[3]

Patient Perspectives

¬†“Delsym (dextromethorphan) has been remarkable for controlling a cough that has persisted since I got over bronchitis about a month ago. No side effects at all. I’m also making sure I’m staying hydrated and have stopped taking menthol cough drops (Ricola) since I read that menthol can make a cough worse. This has really helped.”


“I had a bad cough for about 3 weeks due to bronchitis. Delsym eased my cough a little and also made me so tired I fell asleep in spite of the throat irritation. My main complaint is that even though I took one recommended dose only at bedtime, I was half asleep all the next day. “


“I took Delsym for my allergies. It worked really good the first two days. But on the third day it made me feel like I was drunk or high, not really dizzy. I was disoriented and couldn‚Äôt focus and my mind was all over the place. I thought that maybe I had just not eaten enough that day or something, but after seeing the reviews I guess other people experienced this too.”

Brandon Simpson, PA-C
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