Related Questions

My two year old was treated with polymyxin b sulfate and trimethoprim. He developed hives all over within five hours. What caused this?

Many causes of hives. A 2 year old with hives 5 hours after taking polymyxin and trimethoprim. Hives most commonly occur in kids because of an underlying viral infection. If there is an allergy to a medication, the hives would usually occur within 30 min to an hour after ingestion. The hives could have been related to either medication. See pediatrician or allergist if not resolving with antihistamines. Read more...