Those abbreviated fatal conditions are severe systemic drug reactions involving skin. They are mostly idiosyncratic - in other words, not really related to the

Those abbreviated fatal conditions are severe systemic drug reactions involving skin. They are mostly idiosyncratic - in other words, not really related to the total dose and not more likely with long term use. Some people are unlucky and get these reactions, presumably due to genetic/immunological factors. HIV infection and SLE are known to increase the risk of TEN and SJS. These reactions are rare, which makes it difficult to precisely quantify the risk. Other drugs which are known to cause these reactions are NSAIDs like ibuprofen, which you can buy from a supermarket, and antibiotics like amoxycillin or bactrim, which doctors prescribe without being particularly concerned about the risk of potentially fatal skin reactions.