What Is Stinging Nettle Rash?

Exploring the great outdoors can also lead to some less-than-pleasant skin irritations. One of those irritations is stinging nettle rash—a rash that comes from contact with a stinging nettle plant.

A stinging nettle rash consists of skin that becomes red, often with white bumps, and can feel like it's burning or stinging. Here's what you should know about stinging nettle rashes—including the most common symptoms and how best to treat the itch and irritation.

Symptoms

Stinging nettle rash closely resembles that of hives, or urticaria, Purvi Parikh, MD, a New York City-based allergist and immunologist at Rochester Regional Health, told Health. The rash can appear on your skin surface, followed by white bumps. It can also burn, itch, or tingle for several hours after coming into contact with the plant; however, the rash may resolve within 24 hours.

Causes

Stinging nettle rashes happen when a person comes into contact with a stinging nettle plant, technically known as Urtica dioica. These plants exist in North America, but some species can also be found in Europe.

The plants have two types of hairs on them—both ordinary and those that sting. The stinging hairs are longer, about 1 millimeter in length, and mainly stick out on the stems and leaves.

The hairs on the plant can cause a reaction. When you come into contact with one of the stinging hairs, a piece breaks off. The plant needles inject the following substances, causing a painful skin reaction—which is an irritant, not an allergic reaction—that feels similar to a bee sting:

• Acetylcholine, a type of neurotransmitter that helps with muscle movement
• Histamine
• Formic acid, a natural substance sometimes found in insect venom
• Serotonin

Treatment

If you do come across a stinging nettle plant and develop a rash, you'll want to avoid scratching, touching, or rubbing your skin. Scratching can irritate your skin more. You should also wear light clothing to prevent further itching.

Home Remedies

Dr. Parikh advised waiting 10 minutes before washing your skin where the plant touched it with soap and water to wash off the chemicals released by the stinging nettles. You can also use other remedies to reduce any itching, such as:

• Baking soda mixed with water
• Cool compresses or ice
• Cooling agents like menthol
  
• Oral antihistamines
• Topical anesthetics
• Topical hydrocortisone creams

When To Seek Medical Treatment

While a short-lived stinging nettle rash is more of an irritation than an allergy, there are rare situations in which someone may be allergic to stinging nettles. In that case, they can experience a severe and life-threatening allergic reaction known as anaphylaxis.

Symptoms of a severe allergic reaction that require immediate medical attention may include:

• Chest tightness
• Diarrhea
• Difficulty breathing or shortness of breath
• Facial, eye, or tongue swelling
• Heart palpitations
• Hives, itchiness, or skin redness
• Lightheadedness or dizziness
• Nasal congestion
• Slurred speech
• Stomach pain
• Unconsciousness

You'll also want to see a healthcare provider if you have a fever with the rash or if it starts to spread all over your body. Blistering, painful, or infected skin rashes are other reasons to seek medical care.

A Quick Review

Stinging nettle rashes can occur if you come into contact with a stinging nettle plant. You may experience a painful, burning, or itching sensation where your body made contact with the plant.

The symptoms should resolve within a day or so. However, be aware of any signs of an allergic reaction and see a healthcare provider for signs of severe allergic reactions or worsening rashes.