A poison ivy rash is caused by an allergic reaction to poison ivy, a three-leaf plant common in the United States.

The rash is caused by urushiol, a sticky oil found in poison ivy sap. This substance is odorless and colorless. If your skin is exposed to urushiol, you may develop a rash called allergic contact dermatitis.

This can happen if you touch live or dead poison ivy plants. It can also happen if you touch animals, clothes, tools, or camping gear that have come into contact with urushiol. The rash may show up immediately or within 72 hours.

In the United States, a poison ivy rash is the most common allergic reaction. About 25 to 40 million cases of this kind of rash are reported yearly. The rash itself isn’t contagious, but the oil can spread to other people.

Symptoms of poison ivy exposure include:

Topical calamine lotion or hydrocortisone cream can reduce itching. You can also take an oral antihistamine.

Some people use apple cider vinegar for poison ivy rash. As an acid, this popular home remedy is thought to dry up urushiol, which reportedly relieves itching and speeds up healing.

There isn’t a lot of recent scientific research on the benefits of treating a poison ivy rash with apple cider vinegar. However, it does have a long history of being used in this capacity.

If you think you’ve been exposed to poison ivy, the first thing to do is wash your skin immediately. Use soap and cool or lukewarm water. Avoid hot water, which may worsen irritation.

Try to wash your skin within five minutes of exposure. During this time, the oil can be removed.

Before you go a step further and decide to use apple cider vinegar to treat a rash from poison ivy, it’s important to note that the National Poison Control center does not recommend using vinegar to treat wounds.

The acidity of apple cider vinegar may also cause chemical burns and irritation if used directly on the skin.

Additionally, apple cider vinegar may only provide temporary relief.

While it may be tempting to reach for this quick home remedy to treat poison ivy, the lack of real scientific evidence, and a plethora of other proven treatments, may — and possibly should — deter you from trying.

There are many home remedies for poison ivy rash. These treatments are thought to soothe itching, dry up the rash, and reduce the risk of infection.

Other natural treatments for poison ivy rash include:

The Food and Drug Administration (FDA) only mentions a cool water compress, colloidal oatmeal bath, and baking soda as home remedies that may actually help. This is because the colloidal oatmeal bath and baking soda may help relieve minor itching and irritation.

After gently washing your poison ivy rash, there are a few common treatments that are almost universally recommended. A few ways to ease the itch of mild cases of poison ivy include:

  • applying calamine lotion
  • taking an oatmeal bath
  • using hydrocortisone cream

Antihistamine pills, like Benadryl, may also help relieve the itch.

More severe cases of poison ivy rash may be treated with corticosteroids or immune suppressants as prescribed by a doctor.

Typically, a poison ivy rash will go away on its own within 1 to 3 weeks. After the first week, it should begin to dry up and fade.

Visit a doctor if your symptoms get worse or don’t go away. You should also seek medical attention if you experience the following symptoms:

These symptoms may indicate a severe allergic reaction or skin infection. Additionally, rashes on your face, genitals, and large areas of your body might need prescription medication.

Poison ivy rashes are the most common allergic reactions in the United States. Classic symptoms include redness, itching, blisters, and swelling. Generally, the rash goes away after one to three weeks.

Apple cider vinegar is often touted as a natural home remedy for reducing the symptoms of poison ivy rash. It’s said to provide relief by drying up the rash. However, the relief will most likely be temporary, and apple cider vinegar may cause skin irritation.

There are many other simple, inexpensive, and medically sound treatments for the itch caused by poison ivy rash, including calamine lotion, oatmeal baths, and antihistamines like Benadryl.