How is the eruption produced in dermatitis medicamentosa?

In some instances it is probably due to the elimination of the drug through the cutaneous structures; in others, to the action of the drug upon the nervous system. The view that the drug acts as a toxin or generates some toxin or irritant material in the blood, to which the eruptive phenomena may be due, has also been advanced.

Dermatitis medicamentosa. Bullous dermatitis from iodide of potassium.

What is the character of the eruption in dermatitis medicamentosa?

It may be erythematous, papular, urticarial, vesicular, pustular or bullous, and, if the administration of the drug is continued, even gangrenous.

Name the more common drugs having such action.

Antipyrin, arsenic, atropia (or belladonna), bromides, chloral, copaiba, cubebs, digitalis, iodides, mercury, opium (or morphia), quinine, salicylic acid, stramonium, acetanilid, sulphonal, phenacetin, turpentine, many of the new coal-tar derivatives, etc.

State frequency and types of eruption due to the ingestion of antipyrin.