Q. How long does it usually take for hives to disappear after a reaction to a drug? With the use of Benadryl?
A. With a drug reactions hives can persist for several days even with Benadryl. The severity and duration of drug reactions varies between individuals and the inciting drug. Sometimes prednisone is required to treat the reaction depending on the severity. It would be prudent for any individual experiencing a suspected drug reaction to see a qualified allergist for evaluation and acute and chronic treatment.
Q. Can someone with a sulfa drug allergy swim in sulphur hot springs?
A. Allergic reactions to sulfa (sulfonamide) medications are not uncommon. However, I know of no relationship between the sulfur mineral and sulfonamide medications or sulfites. Furthermore there is no knows relationship between having reactions to sulfites, frequently added to foods and beverages as a preservative, e.g. wine, and sulfonamide medication allergies. Thus I do not believe that soaking in the sulfur hot springs would have any adverse effect, although I have not been able to find any published articles on this topic.