This is what I was able to dig up.

SJA is a rare and potentially dangerous disease that is usually caused by an allergic reaction to medication. There is also a more acute variant of the disease called Toxic Epidermal Necrolysis (TEN). If untreated, SJS can develop into TEN. Both diseases cause the death of epidermal cells, leaving the patient highly susceptible to infection.

Symptoms of SJS

Initial symptoms are similar to those associated with common diseases: fever, a sore throat, and fatigue. Because it is an unusual disease the initial diagnosis is often wrong, with symptoms being interpreted as indicative of an infection or perhaps bronchitis. As the disease progresses the patient develops blisters and ulcers in the mucus membranes, most often in the mouth and on the lips; these conditions may also extend to the anus and genital areas. Additional ulcers develop on the upper body, arms, legs, and soles of the feet. The lesions in the mouth can make eating and drinking difficult. Eventually the disease causes the death of epidermal cells; at that point the body begins to shed the outer layer of skin.

Causes of SJS

While the exact cause of SJS remains unclear, antibiotics are believed to be a likely trigger for the disease along with antibacterial sulfa drugs. An allergic reaction to many other drugs may cause Stevens-Johnson Syndrome; included in that list are Depakote, Levaquin, Dilantin, Accutane, Aloprim, carbamazepine, penicillin, barbiturates, some antifungal drugs, and medication prescribed for gout. There is also evidence that adults can develop SJS with an allergic reaction to a nonsteroidal anti-inflammatory drug (NSAID) such as ibupropin and aspirin.

Treatment of SJS

Once it is diagnosed physicians are likely to treat SJS as a serious medical problem requiring immediate attention. As the body sheds skin it becomes much more susceptible to infection. The first step is discontinuation of all medications that have been recently prescribed. Fluids may be provided to the patient intravenously and if necessary, nutrition may be provided through a gastric tube.

Sources:
Steven Johnson Disease
SJS @ Wikipedia