Key Takeaways

  • While high heat can kill lice and their eggs, using a blow-dryer may not be effective or safe due to the risk of scalp burns from prolonged exposure to temperatures above 130°F (54°C).
  • Over-the-counter treatments, as well as methods like wet combing and smothering, are more effective for eliminating lice.
  • If home treatments for lice are not successful or become overwhelming, consulting a doctor is recommended to explore other treatment options.

Head lice are parasitic insects that people may find in hair, eyebrows, or eyelashes. Although they don’t spread disease, they feed on your blood, and people can quickly pass them on to each other.

There are numerous ways to get rid of lice, but some methods may be ineffective and cause more harm than good.

Let’s examine whether blow-drying hair can kill lice, effective lice treatments, and when to consult a doctor.

Currently, there is limited research on whether the heat from a blow dryer can kill lice. A 2006 study found that hot air from various sources had differing levels of effectiveness in killing lice.

Scientists agree that hot air at temperatures greater than 130°F (54°C) kills lice and their eggs. Air must flow at this temperature for at least 5 minutes.

However, this level of heat so close to the scalp may cause discomfort and pain, and may even result in burns if the heat source remains in close contact with the scalp for more than a few seconds.

Lice eggs (nits) and heat

Lice eggs, called nits, die under high temperatures.

That’s why, in addition to treating for lice, experts also advise washing and drying clothing, towels, and bedding in hot water and on hot air dryer cycles.

Aside from the risk of burning your scalp due to prolonged exposure to heat in the same spot, there are other considerations to make when deciding whether to use a blow dryer to kill lice.

Ineffective treatment method

Because holding the required temperature in the same spot can become painful, using a blow dryer to kill the lice can be ineffective as you will not be able to maintain the required temperature.

Lice transfer

The force of the air from a blow dryer can cause lice to dislodge and transfer to other people, leading to a more widespread lice outbreak.

There are effective over-the-counter (OTC) treatments, prescription remedies, and other methods for lice removal, many of which are approved by the Food and Drug Administration (FDA).

OTC treatments

OTC treatments for lice, such as pyrethrin (Rid) and permethrin (Nix), are organic compounds. Essentially, these are neurotoxins that cause lice paralysis and death.

People with ragweed allergies may experience a reaction to these treatments, but the risk is low. Nonetheless, since they’re neurotoxins, use these treatments carefully to avoid adverse effects.

Prescription medications

A doctor may prescribe medications if home care doesn’t help you get rid of lice. These include:

  • Malathion 0.5% lotion (Ovide): Compared with treatments like Nix, Malathion lotion has a higher effectiveness rate.
  • Spinosad 0.9% suspension (Natroba): Spinosad is proven effective and is FDA approved to kill several types of insects, including many species of lice. Experts do not recommend this treatment for infants under age 6 months.
  • Ivermectin 3-milligram tablet: Ivermectin, an anthelmintic, causes paralysis and death of lice. Experts only recommend it if other available treatments don’t clear up head lice effectively. Concerns exist that oral ivermectin may cross the blood-brain barrier and that children may have an adverse reaction.
  • Lindane lotion: While this medication is effective for treating lice, it is no longer available in the United States due to its neurotoxicity.

Malathion lotion heat warning

Malathion lotion (brand name Ovide) is a prescription-only lice medication that is known to react dangerously to heat.

While using malathion lotion, do not mix treatment methods, smoke, or let anyone in the room smoke.

Keep away from heat sources, such as open fires or stoves, and unplug appliances like curling irons, hair dryers, and space heaters.

Wet-combing

Combing through wet hair is still one of the most effective ways to remove lice and nits. Follow the steps below to try wet-combing:

  1. Spray down the hair with water or rinse out the medicated shampoo.
  2. Separate small sections of hair and comb through them with a fine-toothed lice or nit comb. Metal combs may work best. Spraying white vinegar on the hair while combing may loosen the nits from the hair shaft.
  3. Pull nits from the hair shaft with or without gloves.
  4. Place nits and lice on a tissue and dispose of it by flushing it down the toilet.
  5. Wash hands and scrub under fingernails.

Smothering lice

Smothering lice may be another effective method for removing them. You can try the steps below to smother lice:

  1. Part the hair and apply olive oil to the scalp, focusing on the root of the hair.
  2. Work the oil into the hair roots, then apply a shower cap or another impermeable head covering. The olive oil cuts off oxygen to the lice, and you may feel them start to move. It can take between 6 and 8 hours for the lice to die.
  3. Leave the oil on the hair while combing out the lice and nits. Use a fine-toothed metal lice or nit comb and work through small sections.
  4. When you finish combing, wash the oil with a clarifying shampoo or dishwashing liquid. It may take more than one wash.
  5. Examine dry hair under bright light for any missed nits.
  6. Place all nits on a tissue and dispose of it in the trash or flush it down the toilet.

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Contact a doctor if home treatment is ineffective or becomes too overwhelming.

There’s medical help for lice treatment, and a doctor can recommend options.

Head lice are parasitic insects that attach to hair follicles and reproduce, laying eggs called nits. They feed on your blood and can cause itching and discomfort, but they do not carry disease.

There are several methods of eliminating lice, one of which is heat treatment. However, the temperature must be above 130°F (54°C) and maintained for more than 5 minutes to kill lice. It’s important to note that using a blow dryer to maintain the required temperature for this length of time can cause scalp burns.

Both over-the-counter and prescription medications are available to eliminate lice. Contact a doctor if home treatment is not effective for you or becomes difficult to manage.