While it’s true that heat kills lice and their eggs (nits), blow-drying your or your kids’ hair to remove lice could be ineffective and even dangerous.
Head lice are parasitic insects people can 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.
Let’s look at whether blow-drying hair kills lice, effective treatments for lice, and when to contact a doctor.
There’s currently little research on whether heat from a blow-dryer can kill lice. For example, a 2006 study showed promise. It found that hot air tested from various sources had different effectiveness levels at killing lice.
Scientists agree that hot air at temperatures greater than
Additionally, malathion lotion, a medication used to treat lice, reacts dangerously to heat. While using the lotion, do not mix treatment methods, smoke, or let anyone in the room smoke. Keep it away from heat sources like fire or stoves, and unplug appliances like curling irons, hair dryers, and space heaters.
Eggs, called nits,
Blow-drying might kill nits. But the heat required to kill them — above 130°F (54°C) for more than 5 minutes — might burn the scalp.
There are effective over-the-counter (OTC) treatments, prescription remedies, and other lice removal methods.
OTC treatments for lice, such as pyrethrin (Rid) and permethrin (Nix), are organic compounds. Essentially, these are neurotoxins that cause lice death and paralysis.
People allergic to ragweed may have allergic reactions to these treatments, but the risk is low. Nonetheless, since they’re neurotoxins, use these treatments carefully to avoid adverse effects.
A doctor may have several medication options to prescribe if home care doesn’t help you get rid of lice. These include:
- Malathion 0.5% lotion (Ovide): Compared with treatments like Nix, it has a higher effectiveness rate. But it’s highly flammable.
- Spinosad 0.9% suspension (Natroba): Spinosad is proven effective and approved by the FDA to kill several types of insects, including many species of lice. Experts don’t recommend this treatment for children under 6 months old.
- Lindane lotion: This is proven effective and FDA-approved for use on adults, but the American Academy of Pediatrics doesn’t recommend this treatment for children.
- 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.
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:
- Spray down the hair with water or rinse out the medicated shampoo.
- 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 you comb may loosen the nits from the hair shaft.
- Pull nits from the hair shaft with or without gloves.
- Place nits and lice on a tissue and flush it down the toilet.
- Wash hands and scrub under fingernails.
Smothering lice may be another effective way to remove them. You can try the steps below to smother lice:
- Part the hair and apply olive oil to the scalp at the root of the hair.
- Work the oil into the roots of the hair, 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 takes 6 to 8 hours for them to die.
- 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.
- When you finish combing, wash the oil with a clarifying shampoo or dishwashing liquid. It may take more than one wash.
- Examine dry hair under bright light for any missed nits.
- Place all nits on a tissue and throw it away or flush it.
Contact a doctor if the home treatment’s 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 suck on your blood and can cause itching and discomfort, but they don’t carry disease.
There are many ways to eliminate lice, one of which is heat. Heat must be above 130°F (54°C) for more than 5 minutes to kill lice. But at that length of time, the heat from a blow-dryer could burn the scalp.
Medications and topical shampoos are available over the counter and with a prescription to eliminate lice. Contact a doctor if home treatment doesn’t work for you or becomes overwhelming.