You have a rash and itching. This is a delayed reaction to the oils of a poisonous plant. It was likely poison ivy or poison oak. An oil called urushiol is found in both poison ivy and poison oak. It's what causes the rash. Health care providers can't always tell which plant caused the rash unless you know for sure which plant you came into contact with.
You likely came in contact with poison ivy or poison oak during the 3 days before your symptoms started. You are more likely to have the rash if you had this rash before. It may take 2 to 3 weeks before the rash appears if you have never had a rash from either plant before.
Your skin will become red and itchy. Small blisters may appear. These can break and leak a clear yellow fluid. This fluid can't cause a rash in others who touch it. The reaction usually starts to go away after 1 to 2 weeks. But it may take 4 to 6 weeks to fully go away.
Home care
Follow these guidelines when caring for yourself at home:
-
The plant oils still on your skin or clothes can be spread to other places on your body. They can also be passed to other people and cause a similar reaction. That’s why it’s important to wash all of the plant oils off your skin and under fingernails. Wash all clothes that you were wearing. Use hot water with regular laundry detergent. Dogs and cats that get into poison ivy may not get a rash, but the plant oils may be on their fur. Be sure to wash your pets too. Wear rubber gloves (such as dishwashing gloves) while rounding up and bathing your pet.
-
Don't use over-the-counter antibiotic creams on the rash. Examples are neomycin and bacitracin. These may make the rash worse.
-
Stay away from anything that heats up your skin. This includes hot showers, hot baths, and direct sunlight. These can make itching worse.
-
Don’t scratch the blisters. Bacteria from under your fingernails can get into them and cause an infection.
-
Put a cold compress on areas that are leaking (weeping) and on blistered areas. Do this for 30 minutes, 3 times a day. To make a compress, dip a washcloth in a mixture of 1 pint of cold water and 1 packet of astringent (aluminum acetate) or oatmeal bath powder (colloidal oatmeal, sold in pharmacies). Keep the solution in the refrigerator for future use.
-
You may take a lukewarm bath if large areas of your skin are affected. Add colloidal oatmeal to the water. Or you can add 1 cup of baking soda to the water. Both baking soda and colloidal oatmeal relieve minor irritation and itching. Aluminum acetate is an astringent that relieves rash.
-
Use hydrocortisone cream for redness and irritation for a rash in a smaller area. But don’t use this if another medicine was prescribed. For severe itching, put an ice pack on the area. To make an ice pack, put ice cubes in a plastic bag that seals at the top. Wrap the bag in a clean, thin towel or cloth. Never put ice or an ice pack directly on the skin. Over-the-counter lotions that have calamine may also be helpful. Skin protectants, such as zinc acetate, zinc carbonate, zinc oxide, and calamine, can dry the oozing and weeping of poison ivy, poison oak, and poison sumac.
-
You can also use an oral antihistamine medicine with diphenhydramine for itching, unless another medicine was prescribed. This medicine may make you sleepy. So be cautious when using this medicine during the daytime and while driving or doing work involving heavy machinery. Don’t use medicine that has diphenhydramine if you have glaucoma. Also don't use it if you are a man with trouble urinating because of an enlarged prostate. Antihistamines with loratadine may cause less drowsiness. They may be a good choice for daytime use.
-
For severe cases, your provider may prescribe oral steroids, such as prednisone. Always take these exactly as prescribed.
Follow-up care
Follow up with your health care provider, or as advised. Call your provider if your rash gets worse or you are not starting to get better after 1 week of treatment.
Call 911
Call
-
Trouble breathing or swallowing.
-
Severe swelling in your face, eyelids, mouth, throat, or tongue.
When to get medical advice
Contact your health care provider or get medical care right away if you have:
-
A rash that spreads to the groin and causes swelling of the penis, scrotum, or vaginal area.
-
Trouble urinating because of swelling in the genital area.
-
Itching that gets worse or keeps you awake at night.
Also call your provider right away if you have signs of infection in the areas of broken blisters, such as:
-
Spreading redness.
-
Pus or fluid draining from the blisters.
-
Yellow-brown crusts forming over the open blisters.
-
A fever of 100.4°F (38ºC) or higher, or as directed by your health care provider.
