Antihistamine pills are used to relieve the symptoms of the rash from poison ivy, oak, or sumac. Prescription medications, such as corticosteroids, may be used for severe rashes. Medicines are also used to make the rash less severe.

Medication Choices

• Antihistamine pills can help relieve itching and dry blisters. Examples include Benadryl (diphenhydramine hydrochloride), which is an over-the-counter medicine, and Vistaril (hydroxyzine hydrochloride), which you get by prescription.
• Corticosteroid pills may be used to treat a moderate or severe rash. These prescription medications help improve or clear up the rash more quickly. Prescription corticosteroid creams, ointments, shots, or gels may also be used, but pills or shots are usually more effective.
• Barrier creams and lotions help prevent the plant oil (urushiol) from coming in contact with the skin or reduce the severity of a reaction. These creams vary in their potency and are not always effective.

You may be able to use a product that dissolves urushiol, such as Tecnu Poison Oak-N-Ivy Cleanser, an organic solvent. These products may reduce the severity of your reaction.

The most common complication of poison ivy, oak, or sumac rash is a secondary infection, usually caused by scratching. When this occurs, your health professional will probably prescribe a type of topical antibiotic cream if the infection is in a small area. Otherwise, you may need systemic antibiotics, given as prescription pills or shots.³

What To Think About

The following medications should not be used for poison ivy, oak, or sumac rash, because they can cause allergy problems of their own:

• Antihistamines applied to the skin (such as Benadryl cream, spray, or gel; Dermamycin).
• Anesthetics applied to the skin containing benzocaine (such as Americaine, Anacaine, Lanacane, Bicozene).
• Antibiotics containing neomycin sulfate (such as Neosporin, Neo-Rx, Mycifradin, Poly-Pred).