Ingredients in some vitamin supplements may cause hives or a skin rash. Treatments include antihistamines and topical corticosteroids.

Solar urticaria is a rare allergic reaction to sun exposure. The condition causes an itchy rash or hives that appear on any skin that has been exposed to the sun. The more skin that is exposed to ...

"Many homes are filled with irritants, and if there's a high enough count of an irritant, you'll react," says Christopher Randolph, MD, an allergy expert at /topics/Yale_University" ...

Skin rashes can have many different causes, one of which is medications. The symptoms of drug-induced skin reactions can range from a mild itchy rash to more serious reactions, such as widespread ...

Discovering a rash around your child’s mouth can trigger immediate concern for many parents. Though these unsettling red patches are frequently attributed to food allergies, the reality is much more ...

Penicillin is a substance produced by penicillium mold. About 80% of people with a penicillin allergy will lose the allergy after about 10 years. Clouds Hill Imaging Ltd./Corbis Documentary via Getty ...

For all the good things it does for us, the sun can also be a menace: It can burn your skin, mess with your eyes, and even damage your vehicle. It might also be responsible for that rash you’ve been ...

Dr. Tiffany Wong, co-lead of a penicillin de-labelling project, has developed a tool for health-care professionals to assess ...

Chlorine is an inorganic chemical that’s used to prevent the growth of microorganisms in the water in swimming pools and hot tubs. It’s usually added at extremely low concentrations to kill the ...

Imagine this: You're at your doctor's office with a sore throat. The nurse asks, "Any allergies?" And without hesitation you reply, "Penicillin." It's something you've said for years – maybe since ...