Diphenoxylate

General information

Diphenoxylate is a synthetic compound designed to have the antidiarrheal effects of the opiates, but it also retains some less desirable opiate effects. It is generally combined with atropine, as co-phenotrope, which was originally added to the formulation in the hope of preventing misuse, although it can itself cause problems, especially if the combination is intentionally or accidentally used to excess.

In one instance keratoconjunctivitis occurred in a patient taking co-phenotrope, confirmed by rechallenge but not with diphenoxylate alone [ ]. Adverse reactions are rare during ordinary use in adults, but children can be particularly sensitive to the adverse effects of both components, and in cases of poisoning complex and prompt measures may be needed, particularly since respiratory depression can be delayed until a day after ingestion and can recur even after a good response to opioid antagonists.