Nettles are plants with sharp hairs on their leaves. If you touch them, these hairs inject irritants into the skin, making it itchy, red and swollen.
Stinging nettle is a common weed. It’s found in gardens, waste areas, near where animals live, and around moist areas such as creeks.
In New Zealand there are 3 species: the native ongaonga (giant tree nettle), and 2 introduced varieties.
Small exposures to nettles can cause local symptoms such as burning, itching, redness, swelling (occasionally small blisters will form) and local numbness. Symptoms are usually self-limiting and resolve within a few days.
In cases where a large area of the body has been exposed to the nettles, or you have been exposed to the nettles for a longer period of time it is possible further symptoms such as inco-ordination, tremor, muscle weakness and faintness may occur.
Self-care for nettle stings
- Wash the area with soap and water as soon as possible to relieve the sting and remove the nettle hairs. If no water is available, clean the area with a cloth or other available material
- Local symptoms of pain and itching can be relieved by applying a moistened cloth and/or ice pack to the area. It is also important to refrain from scratching or rubbing the itchy areas
- Antihistamines may be effective in relieving local itching and swelling, while creams such as hydrocortisone containing creams can help reduce inflammation. These are available at your local pharmacy
- Use cool, light, bedding and clothing as this will also help relieve itching
- Avoid extreme heat- have lukewarm baths and showers.
The National Poisons Centre is available 24 hours a day on 0800 764 766 for advice on first aid and treatment of stings.
- Do not give aspirin (acetylsalicylic acid) or aspirin-containing products to anyone 18 years or younger because of the risk of a serious illness called Reye’s syndrome.
- Take non-steroidal anti-inflammatory drugs (NSAIDs) with food or milk to prevent stomach irritation. Do not give NSAIDs to anyone with:
- NSAID-induced asthma
- increased risk of bleeding, such as ulcer disease, a bleeding disorder, if taking blood thinners (anticoagulants), or following surgery, significant trauma or major dental work
- an allergy to NSAIDs.
When to see a doctor
While most nettle stings require no further treatment, seek immediate medical attention if you develop:
- Loss of co-ordination
- Muscle weakness
- Breathing problems
- Swelling under the skin
- Abdominal pain
You should also seek medical attention if there is significant skin itching or rash that is not resolving with self care.