Are there official recommendations for treating erythema multiforme?

Evaluate cause. Ruling out possible immunologic causes, including autoimmune, infection, or allergic reactions is first step, before initiating therapy such as prednisone.
See a dermatologist. Most em is erythema multiforme minor due to herpes. Every time you get a recurrence of a cold sore or other herpes you take a dose of Acyclovir pills or valacyclovir. This will prevent em. Erythema major can be serious , is most often an allergy to sulfonamide (smz/tmp) but may have numerous other causes. Treatment can be difficult , especially regarding the eyes.
Try these. Find british guidelines here: http://bestpractice.Bmj.Com/best-practice/monograph/367.Html. I'm not certain that their official guidelines. Not aware of american guidelines for treating this self-limited disease.

Related Questions

How long does it take for erythema multiforme to clear up?

2-6 weeks. It depends on what caused it in the first place and whether or not it is mild or severe. Read more...
Erythema multiforme. It depends on the cause, and whether or not the cause is diagnosed and treated. If it's a drug side effect and the drug is stopped, it may start to clear up quickly, in a few days. If it's due to a chronic auto inflammatory condition, it could last a long time, or come and go with flares of the illness. Read more...

What symptoms of erythema multiforme are the most important?

Redness and swelling. Watch out for progressive and severe redness and swelling that may produce blistering which may lead on to secondary bacterial infections. Read more...