Fixed drug reaction

Fixed drug reactions, are common and so named because they recur at the same site with each exposure to a particular medication. Medications inducing fixed drug eruptions are usually those taken intermittently.
Signs and symptoms.
A painful and itchy reddish/purple patch of skin that occurs in the same location with repeated exposures to the culprit drug is the classic presentation of a fixed drug reaction. The lips, genitals, and hands are often involved.
Cause.
Medications that are commonly implicated as a cause of fixed drug eruptions include the following: