Coricidin

Coricidin, Coricidin 'D' (decongestant), or CoricidinHBP (for high blood pressure), is the name of a drug marketed by Schering-Plough that contains dextromethorphan (a cough suppressant) and chlorpheniramine maleate (an antihistamine). Varieties of Coricidin may also contain acetaminophen (an analgesic/antipyretic) and guaifenesin (an expectorant).

Coricidin is used to alleviate coughs and includes chlorpheniramine for people with high blood pressure. Other versions of Coricidin are used to reduce fever or as an expectorant. Side effects include diarrhea and hallucination, and long-term use can result in psychosis and erectile dysfunction.

Coricidin is sometimes used in high doses as a recreational drug because it contains the dissociative dextromethorphan. In this context, Coricidin is referred to as C's, Red Devils (Red D's), Skittles, Trips, or Triple C's.

Chlorpheniramine is an anticholinergic that can cause very serious reactions in high doses. This may be compounded by the fact that dextromethorphan and chlorpheniramine are both metabolized by CYP2D6 isozyme of Cytochrome P450. This could increase the plasma concentration of both drugs by inhibiting metabolism and increasing blood serum concentrations. Another danger is chlorpheniramine's notably long half life (about a whole day), which may result in high levels of it building up in one's body if Coricidin is abused frequently. Fatalities have resulted from overdoses of chlorpheniramine.

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