Codeine (methylmorphine, morphine monomethyl ether) belongs to the opiod group. The main indication of codeine is as a cough suppressant.
Intravenous use in children.
General: arterial hypotension (intravenous route), pseudoscarlet fever.
Cutaneous: pruritus, urticaria, macular and maculopapular eruptions, angioedema, erythema multiforme, erythema nodosum, scarlatiniform rashes, fixed drug eruption (occupational dermatitis from codeine has been reported).
Skin patch-tests:codeine phosphate 0.1% aq. (fixed drug eruption).
codeine phosphate 0.001% to 0.033% aq. (urticarial rash).
Oral challenge tests (fixed drug eruption).
Non immunological histamine release (pruritus, urticaria).
Delayed-type hypersensitivity (urticaria, rash).
Vasomotor depression, ganglionar blockade and histamine release could explain hypotension.
Avoid intravenous use in children.
The risk of cross-sensitivity is higher with morphine congeners than with phenylpiperidine or methadone-type agents.