What do you understand by dermatitis medicamentosa?

Under this head are included all eruptions due to the ingestion or absorption of certain drugs.

In rare instances one dose will have such effect; commonly, however, it results only after several days' or weeks' continued administration. With some drugs such effect is the rule, with others it is exceptional, nor are all individuals equally susceptible.

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.

Not uncommon. Erythematous, morbilliform and erythemato-papular; itching is usually present and moderate desquamation may follow. Acetanilid, sulphonal, phenacetin, and other drugs of this class may provoke like eruptions.

Mention frequency and types of eruption due to the ingestion of arsenic.

Rare. Erythematous, erythemato-papular; exceptionally, herpetic, and pigmentary. Herpes zoster has been thought to follow its use. Keratosis of the palms and soles has also been occasionally observed, which, in rare instances, has developed into epithelioma.

Mention frequency and types of eruption due to the ingestion of atropia (or belladonna).

Not uncommon. Erythematous and scarlatinoid; usually no febrile disturbance, and desquamation seldom follows.

Give frequency and types of cutaneous disturbance following the administration of the bromides (bromine).

Common. Pustular, sometimes furuncular and carbuncular and superficially ulcerative. In exceptional instances papillomatous or vegetating lesions have been observed. Co-administration of arsenic or potassium bitartrate is thought to have a preventive influence in some cases.

State frequency and types of cutaneous disturbance due to the administration of chloral.

Occasional. Scarlatinoid and urticarial, and exceptionally purpuric; in rare instances, if drug is continued, eruption becomes vesicular, hemorrhagic, ulcerative and even gangrenous.

State frequency and types of eruption following the administration of copaiba.

Not uncommon. Urticarial, erythemato-papular and scarlatinoid.

Mention frequency and types of eruption resulting from the ingestion of cubebs.

Uncommon. Erythematous and small papular.

Fig. 14.

A somewhat rare form of eruption from the ingestion of iodine compounds.

(After J.C. McGuire.)

Mention frequency and types of eruption resulting from the administration of digitalis.

Exceptional. Scarlatinoid and papular.

State frequency and types of eruption resulting from the iodides (iodine).

Common. Pustular, but may be erythematous, papular, vesicular, bullous, tuberous, purpuric and hemorrhagic. Co-administration of arsenic or potassium bitartrate is thought to have a preventive influence in some cases.

Give the frequency and types of eruption observed to follow the administration of mercury.

Exceptional. Erythematous and erysipelatous.

Give the frequency and types of the cutaneous disturbance following the ingestion of opium (or morphia).

Not uncommon. Erythematous and scarlatinoid, and sometimes urticarial.

Mention the frequency and the types of eruption following the administration of quinine.

Not infrequent. Usually erythematous, but may be urticarial, erythemato-papular, and even purpuric. There is, in some instances, preceding or accompanying systemic disturbance. Furfuraceous or lamellar desquamation often follows.

State frequency and types of eruption resulting from the ingestion of salicylic acid.

Not common. Erythematous and urticarial; exceptionally, vesicular, pustular, bullous, and ecchymotic.

Give frequency and type of cutaneous disturbance due to the administration of stramonium.

Not common. Erythematous.

State frequency and types of eruption resulting from the administration of turpentine.

Not uncommon. Erythematous, and small-papular; exceptionally vesicular.