Usually, it’s pretty easy to determine whether you have crabs. The primary symptom of crabs is intense itching in the pubic region.

Crabs or pubic lice are tiny parasitic insects that feed on blood, which means they bite. Your body has an allergic reaction to these bites that makes them super itchy (think mosquito bites). The itching typically starts about five days after you are exposed.

How to spot pubic lice (Crabs)

When looking closely, you may be able to spot individual crabs or their eggs. Sometimes they can be hard to see, so you might want to use a flashlight and magnifying glass. Consider holding a mirror down there if you need a better angle.

The tiny crab-like bugs are usually tan or whitish-gray, but they can appear darker when they’re full of blood. Their eggs, known as nits, are very tiny white or yellowish ovals that clump together at the base of your pubic hair. Nits can be hard to see without magnification.

If you can’t see anything, then you should have a doctor examine you. Your doctor can look for crabs using a microscope. If it’s not crabs, your doctor can look for other causes of itching.

You might also notice dark, bluish spots on your skin. These marks are a result of the bites.

Crabs prefer coarse hair and can sometimes affect other thicker hairs on your body. This can cause itching in other places. Crabs rarely affect the hair on your head. They can be found on:

  • beards
  • mustaches
  • chest hair
  • armpits
  • eyelashes
  • eyebrows

Most people get crabs through sexual activity with a person who already has pubic lice. Typically, this happens when your pubic hair comes into contact with theirs, but you can also get them when another kind of coarse hair, such as your mustache, touches an area of someone’s body infested with crabs.

Although it’s less common, it is possible to catch crabs when sharing the sheets, clothes, or towels of another person who has crabs.

Crabs can be treated with either over-the-counter (OTC) or prescription medications. Treatment options include gels, creams, foams, shampoos, and pills that kill the lice and their eggs.

OTC treatments are usually strong enough to kill crabs, although you may need to use the treatment more than once. Common brands include Rid, Nix, and A-200.

Shop for lice treatment online.

If the OTC treatment doesn’t work or you’re looking for something stronger, your doctor can give you a prescription for one of the following:

  • Malathion (Ovide). A prescription lotion.
  • Ivermectin (Stromectol). An oral medication taken in a single dose of two pills.
  • Lindane. A highly toxic topical medication only used as a last resort.

If you have crabs in the eyelashes or eyebrows, you’ll need to take special care. Most of the OTC and prescription medications are not safe to use around the eyes. Talk to your doctor about your options. You may need to apply petroleum jelly to the area every night for several weeks.

Crabs don’t disappear after the treatment kills them. To remove crabs from your body, use a fine-tooth comb or your fingernails to pick out the lice and nits. Most OTC treatments come with a comb.

You can get crabs any time you are exposed to them. Your chance of reinfection increases if one of your sexual partners fails to get treatment.

To prevent reinfection, make sure your sexual partners seek treatment immediately. They can use an OTC treatment even if they haven’t spotted any crabs yet.

Crabs and their eggs can live in bedding and clothes. To prevent reinfestation, you’ll need to make sure all your sheets and towels are washed in hot water. You will also want to wash any clothing you wore while you had crabs.

Most cases of crabs can be self-diagnosed at home, but only a doctor can tell you for sure whether or not you have crabs.

There are many conditions that can cause itching in the genital area, including several sexually transmitted infections (STIs). Your doctor can perform a physical exam and test for other STIs, just to be safe.

If you are using an OTC treatment for pubic lice, give it about a week. You may need to repeat the treatment once or twice before all the crabs disappear.

If your condition hasn’t resolved within two or three weeks, make an appointment with your doctor. You may need a prescription-strength treatment.

It is usually pretty easy to determine whether you have crabs. You should be able to see tiny crab-shaped insects and clumps of white eggs at the base of your pubic hair. Fortunately, crabs are quite common and easily treatable.

Healthline and our partners may receive a portion of revenues if you make a purchase using a link above.