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Key Points

• Lice is a highly contagious condition caused by a tiny insect (a louse). The insects can look like white or yellow tear-shaped eggs attached to hair shafts.
• Dandruff is a skin condition that causes white or yellow flakes of dry skin. It’s not contagious.
• Both lice and dandruff can cause itchy scalps. But treatment for each of these problems is very different. If you’re not sure what’s going on, talk to a healthcare provider to make sure you get the right treatment.

If you’re newly dealing with a torturously itchy scalp, you probably want to discover the source of the fury ASAP. Depending on your lifestyle, lice or dandruff could be the culprit. With a close look, it’s rather easy to tell the two conditions apart. And luckily, you can treat most cases with

over-the-counter products.

But if you’re not confident you’ve nailed the diagnosis—or you have a serious case of dandruff that requires prescription medication—a licensed provider can offer tons of help.

Read on to learn the details between dandruff and lice. Plus, how you can get prescription dandruff treatment online with a convenient Dr. B consultation.

What is dandruff?

The medical term for dandruff is seborrheic dermatitis. It’s a chronic skin condition that causes dry, flakey skin on the scalp. Fortunately, special creams or medicated shampoos can treat it.

Symptoms of dandruff include:

• White flakes that fall off easily
• A scalp that feels either very dry or very oily
• Skin redness and itching
• Symptoms that get worse in colder months or during stressful periods

Dandruff is caused by inflammation. This inflammation happens in response to a type of yeast called Malassezia. Most people have this type of yeast on their skin without it causing any symptoms. But in others, it can trigger an immune reaction and lead to dry, flakey skin.

Anyone can get dandruff. But it’s more common in males and people with compromised immune systems. When it happens in babies, it’s called cradle cap and usually gets better by age one without treatment.

What are lice?

Lice are tiny insects that live on the scalp, eyebrows, or eyelashes and feed on human blood. (Yuck.)

Nits are lice eggs. They attach to the hair shaft near the scalp and look like yellow or white teardrops. They don’t come off easily. (Unlike dandruff, which easily flakes off.) Adult lice are black, brown or tan. They’re about the size of a sesame seed. You’re more likely to see them around the ears or neckline.

When an adult louse bites, it causes an allergic reaction, which leads to intense itching. Some people report feeling a crawling or tickling sensation on their scalp. Lice are most active at night, so severe itching can make it hard to sleep. Some people even develop red or bleeding scalps from scratching the itch.

Lice spread via head-to-head contact with another person. Children between 3 and 11 get lice most frequently, but their household members and some people who play sports (like wrestlers) are also at risk.

Hygiene has nothing to do with lice. You can have a clean house and bathe regularly and still get lice. Dogs, cats and other pets do not spread lice.

How to know if you have lice or dandruff

If you look closely at the scalp, you should be able to tell the difference between these two conditions.

• Dandruff flakes are white and fall off the scalp easily.
• Lice eggs stick to hair strands (not the scalp) and are hard to remove.
• While anyone can get lice, it’s most common in children ages 3-11.
• While both conditions can lead to itchy scalps, lice tend to cause severe itching. The itching with lice is also worse at night.

Treatment options for lice

Over-the-counter lice treatments are available at most pharmacies and grocery stores. Treatment usually involves a medicated shampoo or gel that kills lice. You also need to carefully comb your hair to remove nits. Prescription medications like Malathion (Ovide lotion) and Ivermectin can help with serious cases.

Most lice shampoos contain a pesticide. If you’re concerned about chemicals, treating a young child, or being pregnant or nursing, talk to your provider first. There’s no evidence that mayonnaise or other DIY treatments can suffocate the insects.

For most lice treatments, you’ll follow these steps:

1. Apply to hair as directed. Don’t use conditioner beforehand since this can make hair too slippery for the medicine to penetrate.
2. Completely coat the hair, paying extra attention around the ears and neckline.
3. Put on clean clothes and let the medicine rest on the hair as directed on the package—for several hours or overnight as needed.
4. Rinse out the medicine or wash your hair as directed.
5. Use a fine-toothed nit comb to remove dead lice or nits from your hair.
6. Every 2-3 days for 2 weeks, check the hair for lice using the fine-toothed nit comb.
7. Apply a second treatment if you find any live lice after 7-9 days.

It’s also important to wash anything that may have come into contact with the infected person’s head in the last 48 hours.

Lice infestations can be tough to treat. It can take several days of careful combing to remove all the nits.

What about house cleaning to remove lice?

You probably won’t get lice from sharing combs, towels or hats. Lice cling to hair shafts and can’t hold on to smooth or slippery surfaces very well.

But it’s still a good idea to wash all linens, bedding, towels, clothes and stuffed animals that could be infected. Wash in hot water (at least 130° F) and dry on high heat for at least 20 minutes. Soak hair brushes or combs in hot water (130° F) for 5-10 minutes.

Also, vacuum couches, car seats, rugs and other fabric-covered items to remove any lice that may have fallen off. You can put items that can’t be washed in a trash bag for two weeks to ensure any remaining lice are dead.

You don’t need to spend money on special lice sprays or deep cleaning methods. Without human blood to feed on, lice die within 1-2 days, and eggs can’t hatch without the heat and humidity of the human head.

How to treat dandruff

For seborrheic dermatitis, most providers will suggest your over-the-counter (OTC) dandruff shampoos first. These contain ingredients like salicylic acid, coal tar, tea tree oil, zinc pyrithione or selenium sulfide. These ingredients interrupt the inflammation cycle in different ways and come in prescription strengths for those who need them.

Antifungal treatments like Ketoconazole and Ciclopirox (Loprox) can clear up fungal infections that contribute to severe dandruff. Since seborrheic dermatitis is a chronic condition, these medicated shampoos might need to be used at least one or two times a week long-term.

Anti-inflammatory medications, like Fluocinolone (Capex) topical corticosteroids, are sometimes used for a short time. These can help relieve itching and redness.

If you’re dealing with an itchy, flakey scalp, you have online options!

Dr. B offers $15 dandruff consultations from the comfort of your own home—no video chat required. After completing a short health questionnaire, a licensed provider will review your health history and symptoms within three business hours. If appropriate, they’ll send a prescription to the pharmacy of your choice.

Sources

Borda, L. J., et al. (2015). Seborrheic dermatitis and dandruff: A comprehensive review. Journal of Clinical and Investigative Dermatology.

Centers for Disease Control and Prevention. Head lice.

Clark, G. W., et al. (2015). Diagnosis and treatment of seborrheic dermatitis. American Family Physician.

MedlinePlus. Head lice.

Tucker, D., et al. (2023). Seborrheic dermatitis. StatPearls Publishing.