Chlorpheniramine Maleate is an antihistamine frequently found in OTC cough prevention medication. For non-discriminating DXM users it can cause serious problems if accidentally/retardedly taken in high doses. Typical dose instructions for adults limit the daily intake to 24 mgs. As with all things, some people have had serious allergic reactions to CPM and so should take caution with its use. It is known to potentiate DXM.
Coricidin Cough and Cold Controversy
In /dis/, feelings about the usage of CPM containing products seem split. There are the "ONLY DXM!!!" warriors and there are the "IT'S PERFECTLY FINE AS LONG AS YOU DON'T GO OVERBOARD." barbarians. Anecdotal evidence taken from users of CCC seems to suggest that taken in lower dosages CPM isn't harmful in the longterm. Coricidin Cough and Cold contains 30mgs DXM/4mgs CPM per pill. The typical recommendation from /dis/ if one chooses CCC is not to use more than one box/two sheets or 16 pills. This equates to 64 mgs of CPM. If additional DXM is required, it should be obtained from DXM only containing products.
If you like your body, liver, and your health, never take CPM at any dose over 40mg. They are commonly the reason for the death in the abuse of CCCs (CPM is never intended for the abuse of CCCs, while DXM is the pursued substance). It is unsure whether its a delirant at "do-able" doses, as it has never been tried to records i could find.