General Guidelines
Treatment for head lice is
recommended for persons diagnosed with an active infestation. All
household members and other close contacts should be checked; those
persons with evidence of an active infestation should be treated. Some
experts believe prophylactic treatment is prudent for persons who share
the same bed with actively-infested individuals. All infested persons
(household members and close contacts) and their bedmates should be
treated at the same time.
Retreatment of head lice usually is
recommended because no approved pediculicide is completely ovicidal.
To be most effective, retreatment should occur after all eggs have
hatched but before before new eggs are produced. The retreatment
schedule can vary depending on whether the pediculicide used is ovicidal
(whether it can kill lice eggs).
When treating head lice,
supplemental measures can be combined with recommended medicine
(pharmacologic treatment); however, such additional
(non-pharmacologic) measures generally are not required to eliminate a
head lice infestation. For example, hats, scarves, pillow cases,
bedding, clothing, and towels worn or used by the infested person in
the 2-day period just before treatment is started can be machine
washed and dried using the hot water and hot air cycles because lice
and eggs are killed by exposure for 5 minutes to temperatures greater
than 53.5°C (128.3°F). Items that cannot be laundered may be
dry-cleaned or sealed in a plastic bag for two weeks. Items such as
hats, grooming aids, and towels that come in contact with the hair of
an infested person should not be shared. Vacuuming furniture and
floors can remove an infested person's hairs that might have viable
nits attached.
Treat the infested person(s): Requires using an over-the-counter (OTC) or prescription medication. Follow these treatment steps:
- Before applying treatment, it may be helpful to remove clothing that can become wet or stained during treatment.
- Apply
lice medicine, also called pediculicide, according to the instructions
contained in the box or printed on the label. If the infested person
has very long hair (longer than shoulder length), it may be necessary
to use a second bottle. Pay special attention to instructions on the
label or in the box regarding how long the medication should be left
on the hair and how it should be washed out.
WARNING:
Do not use a combination shampoo/conditioner, or conditioner before
using lice medicine. Do not re-wash the hair for 1-2 days after the lice
medicine is removed.
- Have the infested person put on clean clothing after treatment.
- If
a few live lice are still found 8-12 hours after treatment, but are
moving more slowly than before, do not retreat. The medicine may take
longer to kill all the lice. Comb dead and any remaining live lice out
of the hair using a fine-toothed nit comb.
- If, after 8-12 hours
of treatment, no dead lice are found and lice seem as active as
before, the medicine may not be working. Do not retreat until speaking
with your health care provider; a different lice medicine
(pediculicide) may be necessary. If your health care provider
recommends a different pediculicide, carefully follow the treatment
instructions contained in the box or printed on the label.
- Nit
(head lice egg) combs, often found in lice medicine packages, should be
used to comb nits and lice from the hair shaft. Many flea combs made
for cats and dogs are also effective.
- After each treatment,
checking the hair and combing with a nit comb to remove nits and lice
every 2-3 days may decrease the chance of self-reinfestation. Continue
to check for 2-3 weeks to be sure all lice and nits are gone.
- Retreatment
generally is recommended for most prescription and non-prescription
(over-the-counter) drugs on day 9 in order to kill any surviving hatched
lice before they produce new eggs. However, if using the prescription
drug malathion, which is ovicidal, retreatment is recommended after 7-9
days ONLY if crawling bugs are found.
Supplemental Measures :
Head lice do not survive long if they fall off a person and cannot
feed. You don't need to spend a lot of time or money on housecleaning
activities. Follow these steps to help avoid re-infestation by lice
that have recently fallen off the hair or crawled onto clothing or
furniture.
-
Machine wash and dry clothing, bed linens, and
other items that the infested person wore or used during the 2 days
before treatment using the hot water (130°F) laundry cycle and the
high heat drying cycle. Clothing and items that are not washable can
be dry-cleaned
OR
sealed in a plastic bag and stored for 2 weeks.
- Soak combs and brushes in hot water (at least 130°F) for 5-10 minutes.
- Vacuum
the floor and furniture, particularly where the infested person sat
or lay. However, the risk of getting infested by a louse that has fallen
onto a rug or carpet or furniture is very small. Head lice survive
less than 1-2 days if they fall off a person and cannot feed; nits
cannot hatch and usually die within a week if they are not kept at the
same temperature as that found close to the human scalp. Spending
much time and money on housecleaning activities is not necessary to
avoid reinfestation by lice or nits that may have fallen off the head
or crawled onto furniture or clothing.
- Do not use fumigant sprays; they can be toxic if inhaled or absorbed through the skin.
Over-the-counter Medications
Many
head lice medications are available "over-the-counter" without a
prescription at a local drug store or pharmacy. Each over-the-counter
product approved by the FDA for the treatment of head lice contains
one of the following active ingredients. If crawling lice are still
seen after a full course of treatment contact your health care provider.
-
Pyrethrins combined with piperonyl butoxide;
Brand name products: A-200*, Pronto*, R&C*, Rid*, Triple X*.
Pyrethrins
are naturally occurring pyrethroid extracts from the chrysanthemum
flower. Pyrethrins are safe and effective when used as directed.
Pyrethrins can only kill live lice, not unhatched eggs (nits). A second
treatment is recommended on day 9 to kill any newly hatched lice before
they can produce new eggs. Pyrethrins generally should not be used by
persons who are allergic to chrysanthemums or ragweed. Pyrethrin is
approved for use on children 2 years of age and older.
-
Permethrin lotion 1%;
Brand name product: Nix*.
Permethrin
is a synthetic pyrethroid similar to naturally occurring pyrethrins.
Permethrin lotion 1% is approved by the FDA for the treatment of head
lice. Permethrin is safe and effective when used as directed. Permethrin
kills live lice but not unhatched eggs. Permethrin may continue to kill
newly hatched lice for several days after treatment. A second treatment
often is necessary on day 9 to kill any newly hatched lice before they
can produce new eggs. Permethrin is approved for use on children 2
months of age and older.
Prescription Medications
The
following medications approved by the U.S. Food and Drug Administration
(FDA) for the treatment of head lice are available only by
prescription. If crawling lice are still seen after a full course of
treatment contact your health care provider.
-
Malathion lotion 0.5%;
Brand name product: Ovide*
Malathion
is an organophosphate. Malathion lotion 0.5% is approved by the FDA
for the treatment of head lice. The formulation of malathion approved in
the United States for the treatment of head lice is a lotion that is
safe and effective when used as directed. Malathion is pediculicidal
(kills live lice) and partially ovicidal (kills some lice eggs). A
second treatment is recommended if live lice still are present 7-9
days after treatment. Malathion is intended for use on persons 6 years
of age and older. Malathion can be irritating to the skin and scalp;
contact with the eyes should be avoided. Malathion lotion is
flammable; do not smoke or use electrical heat sources, including hair
dryers, curlers, and curling or flat irons, when applying malathion
lotion and while the hair is wet.
-
Benzyl alcohol lotion (5%);
Brand name product: Ulesfia lotion*
Benzyl
alcohol is an aromatic alcohol. Benzyl alcohol lotion 5% is a white
topical lotion approved by the FDA for the treatment of head lice; it is
considered safe and effective when used as directed. Benzyl alcohol
kills live lice (it is pediculicidal) but does not kill unhatched lice
eggs (it is not ovicidal). A second treatment with benzyl alcohol lotion
is necessary on day 9 after the first treatment (or as recommended by
the manufacturer) to kill any newly hatched lice before they can produce
new eggs. Benzyl alcohol lotion is intended for use on persons who are 6
months of age and older. Benzyl alcohol can be irritating to the skin
and eyes; contact with the eyes should be avoided.
-
Lindane shampoo 1%;
Brand name products: None available
Lindane
is an organochloride. The American Academy of Pediatrics (AAP) no
longer recommends it as a pediculocide. Although lindane shampoo 1% is
approved by the FDA for the treatment of head lice, it is not
recommended as a first-line therapy. Overuse, misuse, or accidentally
swallowing lindane can be toxic to the brain and other parts of the
nervous system; its use should be restricted to patients for whom prior
treatments have failed or who cannot tolerate other medications that
pose less risk. Lindane should not be used to treat premature infants,
persons with HIV, a seizure disorder, women who are pregnant or
breast-feeding, persons who have very irritated skin or sores where the
lindane will be applied, infants, children, the elderly, and persons who
weigh less than 110 pounds.
When treating head lice
- Do
not use extra amounts of any lice medication unless instructed to do so
by your physician and pharmacist. The drugs used to treat lice are
insecticides and can be dangerous if they are misused or overused.
- Do
not treat an infested person more than 2-3 times with the same
medication if it does not seem to be working. This may be caused by
using the medicine incorrectly or by resistance to the medicine.
Always seek the advice of your health care provider if this should
happen. He/she may recommend an alternative medication.
- Do not use different head lice drugs at the same time unless instructed to do so by your physician and pharmacist.