Home Treatment

The rash (allergic contact dermatitis) from poison ivy, oak, or sumac typically is mild and can be treated at home. Home treatment for the rash usually helps relieve symptoms rather than speeding up the time it takes the rash to heal.

• If you know you had contact with one of the plants, immediately wash areas of the skin that may have touched the plant. Sometimes the rash can be completely avoided by washing the affected areas with plenty of water. Clothing and other items that may have oil on them should be thoroughly washed right away too.
• To relieve itching and help blisters dry out, apply wet compresses or soak the area in cool water. Antihistamine pills or calamine lotion may help relieve symptoms.
• To prevent infection, try not to scratch the rash. Also, cut your fingernails short to minimize the possibility of opening the skin and spreading bacteria.

Medications

Antihistamine pills are used to relieve the symptoms of the rash from poison ivy, oak, or sumac. Prescription medicines, 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), which is an over-the-counter medicine, and Vistaril (hydroxyzine), which you get by prescription.
• Corticosteroids may be used to treat a moderate or severe rash. Corticosteroids may be given as pills, products that are spread on the skin (creams, ointments, gels), or shots.
• 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 or Zanfel. These products are used to wash the oil off your skin or other objects. They may reduce the severity of a reaction or prevent one.

The most common complication of poison ivy, oak, or sumac rash is a secondary infection, usually caused by scratching. When this occurs, your doctor 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 pills or shots.

What To Think About

The following medicines 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 diphenhydramine (found in Benadryl cream, spray, or gel).
• Anesthetics applied to the skin containing benzocaine (such as Lanacane).
• Antibiotics containing neomycin (such as Neosporin or Poly-Pred).