Treatment |
Ovicidal? |
Mechanism of action |
Directions (per package inserts) |
Effectiveness |
Cost* |
Comments |
Benzyl alcohol 5% lotion (Ulesfia); prescription |
No |
Suffocation |
Apply to dry hair, leave on for 10 minutes then rinse; repeat in seven days |
75% to 76% of patients are lice free at 14 days11 |
— ($450) for two bottles |
Can be costly for long hair (dosing is based on hair length) Must be used in conjunction with a lice comb (also called nit comb) Approved for persons six months and older, may be used in pregnant and lactating women |
Dimethicone solution (Nix Ultra, Lice MD); OTC |
No |
Suffocation |
Spray all over dry hair, and massage until wet; let it sit for 30 minutes, then comb into hair; leave on overnight; wash out, and use a lice comb; repeat in eight to 10 days |
70% to 96% of patients are lice free at 14 days (study of dimethicone 100%)12,13 |
— ($10 to $20) for one bottle |
May cause eye irritation Should not be used in children younger than two years |
Isopropyl myristate (Resultz); OTC† |
No |
Exoskeleton dissolution |
Apply to dry hair and scalp, leave on for 10 minutes then rinse with warm water; repeat in eight to 10 days |
54% to 82% of patients are lice free at 14 to 21 days12 |
— |
May cause local and eye irritation Not recommended for children younger than four years |
Ivermectin 0.5% lotion (Sklice); prescription |
Not directly, but lice hatched from treated eggs die within 48 hours |
Neurotoxic to lice4 |
Apply to dry hair and scalp, leave on for 10 minutes then rinse; one application is sufficient |
74% of patients are lice free at 15 days14 |
— ($360) for one tube |
Rare adverse effects include skin and eye irritation, erythema, burning, dryness |
Ivermectin, oral (Stromectol); prescription‡ |
Partial |
Neurotoxic to lice |
200 mcg per kg, two doses seven to 10 days apart8 |
92% to 97% of patients are lice free at 14 to 15 days after two doses15 |
$5 ($8) for one 3-mg tablet (dosing varies based on weight) |
Do not use in children weighing less than 33 lb (15 kg) or in pregnant women |
Malathion 0.5% lotion (Ovide); prescription |
Partial |
Neurotoxic to lice |
Apply to dry hair until hair and scalp are wet, allow to dry naturally, shampoo eight to 12 hours later, rinse and use a lice comb; repeat after seven to nine days only if live lice are still present |
80% of patients are lice free at 14 days16 |
$150 ($270) for one bottle |
Flammable; do not use with a hair dryer or near cigarettes or an open flame |
Permethrin 1% shampoo (Nix); OTC |
No |
Neurotoxic to lice |
Apply to damp hair, leave on for 10 minutes then rinse; repeat in seven days |
50% to 97% of patients are lice free at 14 days1,8,17 |
$20 for two treatments |
First-line treatment1 |
Pyrethrins 0.3%/piperonyl butoxide 4% shampoo or mousse (Rid); OTC |
No |
Neurotoxic to lice |
Apply to dry hair, leave on for 10 minutes then rinse; repeat in seven days |
62% to 94% of patients are lice free (unclear time frame)1 |
— ($15 to $20) for two treatments |
Piperonyl butoxide is thought to prolong the activity of pyrethrins Avoid in patients with chrysanthemum allergy |
Spinosad 0.9% suspension (Natroba); prescription |
Yes |
Neurotoxic to lice |
Apply to dry hair, leave on for 10 minutes then rinse; repeat in seven days only if live lice are present |
68% to 87% of patients are lice free at 14 days16 |
$200 ($280) for one bottle |
May be used without a lice comb, although use of a lice comb improves results Safe for use in children four years and older Do not use in infants younger than six months because it contains benzyl alcohol |