Summer’s heat and humidity are a paradise for mosquitos and many other biting, stinging insects and animals. While some skin ailments are a nuisance and need only time and topical cures to heal, others can lead to more serious consequences.

The cause of skin reactions can be tricky to discern, so we asked dermatologist Larry Millikan, MD, Professor and Chairman Emeritus of Dermatology at Tulane University, for tips on how to recognize various bites and rashes and how to treat them properly.

1. Mosquito bites

Symptoms: Puffy, hive-like bumps that become itchy, red, and irritated

How to soothe the bite: Apply a soothing cream or lotion. Dr. Millikan recommends hydrocortisone creams, anti-itch creams like Sarna or Gold Bond topical cream. “Some of the old wives’ tales — like using your fingernail to press an X into the center of a bite — may work once in a while, but it’s a counter-irritant phenomenon,” he says. “The itching will come back.”

When to seek medical help: “If you get a lot of bites and have hives or swelling elsewhere, you need to take an antihistamine,” says Dr. Millikan. Only a secondary infection, usually caused by excessive scratching, makes a doctor’s visit necessary, because it can lead to anything from impetigo to staph or strep.

“Fun” fact: Only female mosquitos bite — they need to feed on blood to cultivate the eggs they produce.

2. Spider bites

Symptoms: Only a few spiders have fangs long enough to pierce human skin: black widow and brown recluse (see spider comparison pictures here). Spider-bite symptoms vary from minimal to severe: Black widow bites can cause radiating pain, abdominal cramping, and excessive sweating, while brown recluse bites appear first as a red spot, which develops into a deep, open sore called an ulcer. “You can have throbbing pain (9 out of 10 on the pain scale),” says Dr. Millikan. “Huge areas of tissue can be destroyed as the ulcer grows.” Ulcers may keep growing for up to 10 days.

How to soothe the bite: Clean the bite with mild soap and water, then apply cold packs and administer OTC pain relievers to reduce pain and swelling. Most spider bites take a few months to heal completely.

When to seek medical help: It’s rare, but a bite from a black widow or brown recluse spider can be lethal, particularly for children or elderly people. If you or your grandkids experience severe pain, abdominal cramping, or a growing ulcer, you should see a doctor.

“Fun” fact: Both black widow and brown recluse spiders only bite when they feel threatened and  prefer warm climates and dark, dry places, like sheds, garages, and woodpiles, according to the Mayo Clinic.

3. Fire ant sting

Symptoms: Reactions vary, but usually, an encounter with fire ants results in multiple stings, both because people generally disturb the whole ant mound and because one fire ant can sting repeatedly. A inflamed lump may form at the site of the stings, which causes pain and burning (8 out of 10 on the pain scale) and can develop into small blisters, or pustules, within 24 hours.

How to soothe the sting: Clean blisters with mild soap and water and resist the temptation to break or pop them; this can lead to secondary infection. Topical hydrocortisone can be applied or oral antihistamines can be taken to relieve pain and itchiness.

When to seek medical help: It’s rare, but any insect sting can provoke a severe allergic reaction. Seek medical attention if symptoms worsen to include nausea, trouble breathing, or excessive swelling.

“Fun” fact: Fire ants will attack anything that disturbs their nest by biting skin and then stinging and injecting venom. Since they can pivot at the head, they’ll often sting in a circular pattern.04

4. Tick bite

Symptoms: Tick bites often go unnoticed unless the insect is still on — or burrowing into — your skin. If the tick falls out cleanly, the bite should heal with no consequence, says Dr. Millikan. But if a tick is allowed to remain in your skin or is removed carelessly, you could be at risk for infection or serious illness, like Rocky Mountain Spotted Fever or Lyme Disease.

How to remove a tick: “The best way is to make them feel unwanted,” says Dr. Millikan, who recommends covering the tick with Vaseline so it can’t breathe or holding something hot to it. If the tick doesn’t release on its own, the CDC recommends using fine-tipped tweezers to grasp the tick as close to the skin’s surface as you can. Then pull upward with steady, even pressure. If the mouth of the tick remains embedded in your skin, leave it alone and let the skin heal. Make sure to clean the affected area with rubbing alcohol, iodine, or soap and water.

When to seek medical help: If a bullseye-shaped rash or fever develops within a few weeks of removing the tick, see a doctor. 

“Fun” fact: Ticks are arachnids — they’re more closely related to spiders and scorpions than insects.

5. Bed bug bite

Symptoms: Few bug bites are scarier than those from a bed bug, but mostly it’s the implication that you’ll have to tear apart your house to get rid of an infestation, rather than the relatively mild symptoms associated with the bites. If you’re allergic to bed bugs (some people aren’t and will not have any symptoms), bites will take a day or two to appear and typically occur in a pattern, like a little highway down your leg or arm. The bite marks are similar to mosquito bites — they’re red, get slightly swollen, and often feel itchy or irritated. 

How to soothe the bite: Treat the symptoms as you would a mosquito bite; the real worry is secondary infection, says Dr. Millikan. Avoid scratching the bites and take an antihistamine to reduce itchiness.

“Fun” fact: Bed bug bites are imperceptible when they happen. The bug’s saliva has anesthetic properties and promotes blood flow at the site, making the whole process painless. Tricky!

6. Bee sting

Symptoms: For most people, bee stings are a nuisance and cause pain similar to that of a fire ant sting, but they’re not life-threatening. There will be an instant, sharp pain at the site, a swollen, red welt, and a small white spot where the stinger punctured your skin. 

How to soothe the sting: “Only honey bees leave a stinger behind,” says Dr. Millikan. “You’ll see it on the surface of your skin. Use tweezers to remove it — it should be done quickly.” To treat the sting, wash the area with soap and water to make sure no venom remains, and soothe it with a cold compress.

When to seek medical help: If you have a large local reaction or are allergic to bees and don’t have an epinephrine injector pen handy, call 911. If you’re not sure whether you have an allergy to bees, the following symptoms will make it clear: difficulty breathing, swelling of the throat and tongue, weak pulse, and dizziness or fainting.

“Fun” fact: Honey bees have to tap the nectar of two million flowers to make one pound of honey.

7. Heat rash

Symptoms: Heat rash usually occurs on moist areas of your body (groin, under arms, etc.) in hot, humid environments. The rash ranges from tiny, fluid-filled blisters to deep, red lumps and can feel prickly or itchy. But beware, scratching the area can lead to a secondary infection.

How to soothe the rash: Getting out of the heat-stressed environment and applying hydrocortisone to the affected area will usually take care of it, says Dr. Millikan.

When to seek medical help: Heat rash usually heals on its own, but if the rash doesn’t clear in a few days or gets worse and is accompanied by fever, pain, or pus, see a doctor.

“Fun” fact: Babies more often get heat rash, because their immature sweat ducts can rupture more easily, which traps perspiration beneath the skin.

8. Poison ivy

Symptoms: If you’ve ever had poison ivy, you won’t soon forget the feeling! Since contact usually occurs when you brush past the leaves of a poison ivy, oak, or sumac plant, the resulting rash often develops as a line of angry, red bumps and streaks that are painfully itchy and often turn into blisters.

How to soothe the rash: “If you know been exposed, hot soapy water will get rid of a lot of it, says Dr. Millikan. Minor cases will respond to remedies you already know, like cortisone or calamine.

When to seek medical help: A serious case that’s widespread, oozes pus, or causes a fever will require a trip to the doctor for a prescription steroid.

“Fun” fact: Pets can be unwitting carriers of poison ivy fluids. If they rub up against a plant and get it on their fur, the substance can transfer to your skin, when you go in for a cuddle.

9. Jellyfish sting

Symptoms: What would summer be without a trip to the beach? But unfortunately, stinging creatures may lurk beneath the water. If you or your grandkids happen to come into contact with jellyfish tentacles, you’ll first notice a painful burning sensation immediately followed by a very characteristic rash of linear red dots — it kind of looks like the person’s been hit with a switch, says Dr. Millikan.

How to soothe the sting: And what about that old wives’ tale that “relieving yourself” on a jellyfish sting will take away the pain? “Soaking the skin with vinegar will neutralize the toxins and is more acceptable, but urine will also do the trick, if no other remedies are available,” he says.

When to seek medical help: You won’t find any lethal jellyfish on a U.S. coast — deadly box jellyfish, also known as sea wasps or marine stingers, are only found off the coast of northern Australia and the Indo-Pacific and release a powerful poison that can kill quickly causing cardiac arrest.

“Fun” fact: Jellyfish tentacles leave thousands of tiny stingers called nematocysts in the skin, which continue to release venom until they are rinsed or scraped off.

See Also: 8 best ways to keep bugs out of your house

The editors of determine the recommendations of products and services that appear in articles through rigorous reporting. If you buy a product from a retailer through a link on the site, may be paid a commission through our participation in an affiliate marketing program. These fees in no way affect our reporting or recommendations.