Pubic lice, also known as crab lice, are small parasites typically found in the pubic area and may spread through sexual contact. Treatment options include over-the-counter medications containing permethrin or pyrethrins, as well as prescription options like lindane and malathion, although the latter is not FDA-approved for pubic lice. Proper treatment involves following instructions carefully and ensuring all sexual partners are informed and treated to prevent reinfestation.

1. Fitango Education
Health Topics
Crabs/Pubic Lice
http://www.fitango.com/categories.php?id=232

2. Overview
Adult pubic lice are 1.1-1.8 mm in length.
Pubic lice typically are found attached to hair in the
pubic area but sometimes
are found on coarse hair elsewhere on the body
(for example, eyebrows,
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3. Overview
eyelashes, beard, mustache, chest, armpits, etc.).
Pubic lice infestations (pthiriasis) are
usually spread through sexual contact. Dogs, cats,
and other pets do not play a
role in the transmission of human lice.
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4. Overview
Both over-the-counter and prescription
medications are available for treatment of pubic
lice infestations.
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5. Diagnosis
Pubic lice are short and crab-like and
appear very different from head and body lice.
Pubic lice infestation is
diagnosed by finding a “crab” louse or eggs on hair
in the pubic region or,
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6. Diagnosis
less commonly, elsewhere on the body (eyebrows,
eyelashes, beard, mustache,
armpit, perianal area, groin, trunk, scalp). Although
pubic lice and nits can
be large enough to be seen with the naked eye, a
magnifying lens may be
necessary to find lice or eggs.
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7. Treatment
A lice-killing lotion containing 1%
permethrin or a mousse containing pyrethrins and
piperonyl butoxide can be used
to treat pubic ("crab") lice. These products are
available
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8. Treatment
over-the-counter without a prescription at a local
drug store or pharmacy.
These medications are safe and effective when
used exactly according to the
instructions in the package or on the label.
Lindane shampoo is a prescription
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9. Treatment
medication that can kill lice and lice eggs. However,
lindane is not
recommended as a first-line therapy. Lindane can
be toxic to the brain and
other parts of the nervous system; its use should
be restricted to patients who
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10. Treatment
have failed treatment with or cannot tolerate
other medications that pose less
risk. Lindane should not be used to treat
premature infants, persons with a
seizure disorder, women who are pregnant or
breast-feeding, persons who have
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11. Treatment
very irritated skin or sores where the lindane will
be applied, infants,
children, the elderly, and persons who weigh less
than 110 pounds.
Malathion* lotion 0.5% (Ovide*) is a
prescription medication that can kill lice and some
lice eggs; however,
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12. Treatment
malathion lotion (Ovide*) currently has not been
approved by the U.S. Food and
Drug Administration (FDA) for treatment of pubic
("crab") lice.
Ivermectin has been used successfully to
treat lice; however, ivermectin currently has not
been approved by the U.S.
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13. Treatment
Food and Drug Administration (FDA) for treatment
of lice.
How to treat pubic lice infestations: (Warning:
See special instructions for treatment of lice and
nits on eyebrows or
eyelashes. The lice medications described in this
section should not be used
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14. Treatment
near the eyes.)
-- Wash the infested area; towel dry.
-- Carefully follow the instructions in the
package or on the label. Thoroughly saturate the
pubic hair and other infested
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15. Treatment
areas with lice medication. Leave medication on
hair for the time recommended
in the instructions. After waiting the
recommended time, remove the medication
by following carefully the instructions on the label
or in the box.
-- Following treatment, most nits will still
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16. Treatment
be attached to hair shafts. Nits may be removed
with fingernails or by using a
fine-toothed comb.
-- Put on clean underwear and clothing after
treatment.
-- To kill any lice or nits remaining on
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17. Treatment
clothing, towels, or bedding, machine-wash and
machine-dry those items that the
infested person used during the 2-3 days before
treatment. Use hot water (at
least 130°F) and the hot dryer cycle.
-- Items that cannot be laundered can be
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18. Treatment
dry-cleaned or stored in a sealed plastic bag for 2
weeks.
-- All sex partners from within the previous
month should be informed that they are at risk for
infestation and should be
treated.
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19. Treatment
-- Persons should avoid sexual contact with
their sex partner(s) until both they and their
partners have been successfully
treated and reevaluated to rule out persistent
infestation.
-- Repeat treatment in 9-10 days if live lice
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20. Treatment
are still found.
-- Persons with pubic lice should be evaluated
for other sexually transmitted diseases (STDs).
Special instructions for treatment of lice
and nits found on eyebrows or eyelashes:
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21. Treatment
If only a few live lice and nits are
present, it may be possible to remove these with
fingernails or a nit comb.
If additional treatment is needed for lice
or nits on the eyelashes, careful application of
ophthalmic-grade petrolatum
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22. Treatment
ointment (only available by prescription) to the
eyelid margins 2-4 times a day
for 10 days is effective. Regular petrolatum (e.g.,
Vaseline)* should not be
used because it can irritate the eyes if applied.
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