Why Do Bug Bites Itch?

Bug bites can range from unpleasant to painful. But most of the time when you’re dealing with an itchy bug bite, you’re dealing with a mosquito bite. When a mosquito bites you, it doesn’t just suck out some of your blood—it actually releases some of its saliva into your skin. (Fleas and ticks do the same. Spiders inject a combination of saliva and venom into your skin when they bite you.) This mosquito saliva is a foreign substance, and your immune system knows that, so it releases histamine—a chemical that makes your capillaries more permeable. This makes it easier for your white blood cells (your immune system cells) to make their way to the site of the bug bite, so they can “fight off” the saliva or venom. Unfortunately, this triggers an inflammatory response—causing the location of your bite to swell and itch. But why do they remain swollen, red, and itchy for days? Simply put: “The histamine released by the white blood cells in our body takes time to clear up,” says Sunitha Posina, MD, a New York City-based board-certified internist. In other words, it takes a few days for your body to recover from the bug bite—and from fighting off the foreign substance. And since scratching can cause the area to become more inflamed, it may take even longer for your bug bites to clear up if you’re touching the area a lot.

How to Stop Bug Bites From Itching

Knowing all that, what can you do to make the reaction less intense once you get a bug bite? Thankfully, there are a few steps you can take to cut down on inflammation—and make your bug bites a little less itchy. And rubbing alcohol may be useful for another reason, too. “It creates a cooling sensation as it evaporates that distracts from the sensation of itch,” says Dina Strachan, MD, a New York City–based dermatologist. So even if you catch a bug bite way after a bug has bitten you, rubbing alcohol may still offer your skin some relief. RELATED: Itchy Skin? Watch Out for These 7 Surprising Culprits That Make Eczema Worse RELATED: 8 Plants That Repel Bugs and Mosquitoes “Hydrocortisone is a type of corticosteroid that mimics [cortisol], the natural steroid in our body,” Dr. Posina says. “It fights by preventing the infection-fighting white blood cells—thus decreasing the inflammatory response and calming the inflammation down.” The nice thing about hydrocortisone is that it’s actually available at most drugstores. So it shouldn’t be too hard to get hold of an over-the-counter (OTC) cream with hydrocortisone in it. Remember that your body also releases histamine when you get a bug bite—and that’s the chemical that causes your skin to swell, itch, and turn red. Because antihistamines block the effects of histamines, they can cut down on some of these familiar bug-bite-related symptoms. “Treat bug bites as you might treat any other allergy,” Dr. Strachan says. “If you know you’ll get bitten, take an antihistamine to reduce the reaction.” Dr. Strachan adds that antihistamines are better at preventing inflammation than they are at treating the itchiness and swelling after the damage is already done. With antihistamines, your goal should be to take one as early as possible once you know you’ve been bitten (if not even before then, for example, if you’re going on a long hike in a buggy locale). OTC antihistamines are widely available at your local drugstore. Note: Always talk to your doctor before taking any OTC antihistamine. These drugs may cause negative side effects when paired with certain medications or cause drowsiness. Call your primary care provider and get the go-ahead before taking one. RELATED: Medicine Cabinet Essentials to Have in Case of Illness or Injury The only downside is that OTC anti-inflammatories might be better at treating pain than they are at treating itching, says Susan Bard, MD, a Brooklyn-based dermatologist at Vive Dermatology. Still, they may be worth a try—especially if you already have one in your cabinet. Note: Some OTC anti-inflammatories don’t pair well with other medications—and definitely don’t pair well with alcohol. Talk to your doctor before taking one. Or—at the very least—read and follow the directions on the bottle. “Icing or cooling numbs the skin,” Dr. Posina says. “That temporarily gives relief for itching and discomfort.” Bonus: It may help you cut down on scratching, which can actually make your inflammation situation worse. If you can find a way to curb your urge to scratch, that is definitely a good thing. Note: Some topical creams containing menthol and camphor can irritate the skin, so read and follow the directions carefully. And talk to your primary care provider if you notice your skin becoming irritated. RELATED: Have Dry Skin? Here’s What Derms Want You to Know There are many OTC numbing creams available at drugstores, so they’re not particularly hard to find. And many of these creams draw on natural ingredients—like arnica, camphor, or menthol—to soothe or numb the skin. However, some of these creams get their numbing power from NSAIDs, or non-steroidal anti-inflammatory drugs. NSAIDs can be an effective way to reduce pain and inflammation, but they do come with side effects, and it is possible to overdose on them. If you decide to use an NSAID-based numbing cream, call your doctor to confirm that’s the right route for you. They can help you navigate any side effects you experience and avoid an NSAID overdose. Note: Stick to one NSAID at a time. NSAIDs are also found in OTC painkillers—like aspirin, ibuprofen, naproxen—so be sure not to accidentally double up on them or take them in combination with each other. “The more you scratch, the more [your immune system] release[s] histamine,” Dr. Bard explains. “This is a vicious cycle that can self-propagate for days.” Curb your scratching habit as much as you can. If you have to, wear gloves to cover your nails, put a bandage over the bite, or simply be disciplined about noticing and stopping yourself anytime you reach for that itchy spot.