Why Mosquito Bites Itch and How to Stop Them

Medically reviewed by Debra Sullivan, PhD, MSN, CNE, COI on March 7, 2017Written by Kathleen Pointer on March 7, 2017

Why do mosquito bites itch?

Many people get bitten by mosquitos each year, but bites can affect people differently. When mosquitoes bite, they draw out blood while injecting some of their saliva. Their saliva contains an anticoagulant and proteins.

The proteins are foreign substances that trigger the body’s immune system. To fight them the body’s immune system releases histamine, a compound that helps white blood cells get to the affected area. Histamine is what causes the itchiness, inflammation, and swelling.

Sometimes if a person is bitten for the first time they won’t have a response. This is because their body hasn’t formulated a response to the foreign invader. And some people may not notice bites at all. Others may build up a tolerance over time.

When an irritating bite does appear, it’s good to know what remedies work to ease the itchiness.

Scratching mosquito bites


Why do mosquito bites itch more after you scratch them?


When you scratch a mosquito bite, this causes the skin to become even more inflamed. Since inflammation causes your skin to itch, you can get into a cycle where scratching will cause even more of an itchy sensation. In addition, by continuing to scratch you run the risk of breaking the skin and causing an infection, leading to even more of an itch.

Debra Sullivan, PhD, MSN, CNE, COIAnswers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.

Immediate relief for mosquito bites

It may take a little experimentation to see what works best for you and your bite. Most of these remedies can be used as many times as needed to soothe the area. For medications, follow the instructions on the bottle.

1. Clean the area with rubbing alcohol

If you catch the bite soon after the mosquito bites you, quickly wipe the bite with rubbing alcohol. Rubbing alcohol has a cooling effect when it dries, which may relieve itching. Avoid using too much alcohol as it can irritate the skin.

2. Apply honey on the bite

Honey is an antiseptic and antibacterial ingredient that also has wound healing properties. It’s to reduce inflammation and can also help prevent infection. Don’t wear it outside, though, because the honey’s sugar can attract more mosquitoes.

Read more: Honey for allergies »

3. Take an oatmeal bath

Oatmeal has active properties that help soothe insect bites and allergic reactions, chicken pox, and dry skin. You can add oatmeal to a bath or apply it as a mask on your bug bite. Make a paste by adding a little water to colloidal oatmeal and apply to the affected area. Wash it off with warm water after 15 minutes. You can also add honey to your paste for extra benefits. Moisturize with a cream after.

4. Use a cold tea bag

Green and black tea’s antiswelling effects may not just be useful for swollen eyes. Tea’s anti-inflammatory effects may help with the swelling. Soak a bag of green or black tea and pop it in the fridge to cool it down. Apply the cold tea bag over the bite to ease the itchiness.

5. Make a basil rub

Basil has chemical compounds that can relieve itchy skin. You can apply basil oil like a lotion or make your own at home. To make your own rub, boil 2 cups of water and 1/2 an ounce of dried basil leaves. After the mixture cools, dip a washcloth into the pot and apply it on the affected area. For a more immediate treatment, chop up fresh basil leaves and rub them on your skin.

6. Take over-the-counter antihistamines

Antihistamines help lower the histamine count in your body and reduce inflammation. These are available over the counter and help with itchiness and swelling. You can take them orally (Benadryl or Claritin) or apply topically (calamine lotion) over the affected area.

7. Use ointments containing lidocaine or benzocaine

Lidocaine and benzocaine are numbing agents in over-the-counter creams. They offer temporary relief from itchiness and pain. For extra benefits, look for creams that contain menthol or peppermint.

8. Apply aloe vera

Aloe vera gel is shown to have anti-inflammatory properties for wound healing and calming infections. The cool feeling of the gel may also soothe any itchiness. Keep an aloe vera plant around the house. You can cut the leaves and apply the gel directly.

9. Mild corticosteroid cream

Doctors recommend corticosteroid creams for itching. These creams are known to help with inflammation for skin irritations, but avoid using them on open wounds or on your face. Long-term use can also cause side effects like thinning or worsening of skin, excessive hair growth, and acne.

10. Dilute minced garlic

Some creams use garlic extract due to its wound healing and anti-viral properties. But don’t rub garlic directly on your skin. Raw garlic can increase skin irritation and inflammation. Instead, dilute minced garlic with coconut oil and apply that to the affected area for a few minutes.

Avoid these home remedies for bug bites

The following treatments have little scientific evidence to back up their effectiveness. They may increase skin irritation or cause unwanted side effects such as acne, burning, dry skin, and more.

  • baking soda
  • lemon or lime juice
  • toothpaste
  • vinegar

See a doctor for your bite if …

If your bite causes anaphylaxis seek medical attention. Anaphylactic shock is a life-threatening condition. You can tell if someone is having this reaction if they:

  • break out in hives
  • start wheezing
  • have difficulty breathing
  • feel as if their throat is closing up

Someone in anaphylactic shock will need an EpiPen injection. But anaphylactic shock for a mosquito bite is rare and more commonly caused by other stinging insects.

Read more: First aid for bites and stings »

For other people, mosquito bites can cause more serious symptoms, such as:

  • blisters,
  • lesions
  • hives
  • high fever
  • swelling in the joints

See a doctor if you experience any of these symptoms along with your mosquito bite. An antihistamine like cetirizine, fexofenadine or loratadine, are all available over the counter. These medications may help curb these bodily responses.

If you’ll be traveling to certain countries, it’s a good idea to see a doctor. Seeing a doctor is also important if you’ve been living or traveling in certain areas of the world where bloodborne diseases like Zika and malaria are common. Mosquitos can spread these diseases from person to person. There are vaccines available for some of these diseases.

How long does a mosquito bite last?

A mosquito bite can last for hours to a few days. The length of a mosquito bite and its symptoms vary depending on the size of the bite and the person’s immune system. Itching or scratching the bite can increase the length of time it lasts.

Sometimes mosquito bites leave small dark marks long after the itching and bite itself have faded. People with sensitive skin tend to have these lingering marks, but they don’t have to be permanent. To avoid hyperpigmentation, look for creams with vitamin C, E, or niacinamide. Don’t forget to apply SPF 30 sunscreen on areas exposed to the sun.

Prevention is key

The best way to avoid mosquito bites is preparation and prevention. Use insect repellant if you are going to places where mosquitos are. Natural insect repellants are effective, but you may want to use commercial ones if you are traveling to another country.

Limiting or avoiding exposure to certain things may help minimize your risk for mosquito bites. Below is a list of things known to attract mosquitos:

  • sweat and body odor
  • light
  • heat
  • lactic acid
  • carbon dioxide

Alcohol intake is also shown to be associated with a higher probability of being bitten. You may want to avoid drinking the night before you’ll be in an area with mosquitos. It may also be a good idea to keep some travel-size aloe vera and alcohol wipes handy.

Keep reading: 10 natural ingredients that double as mosquito repellants »

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