from Mosby's Department of Continuing Education and Training
Mosby ContinuingEducation and Training is accredited as a provider of continuing education innursing by the AmericanNurses Credential
Center’s Commission onAccreditation (ANCC-
Biology, Diagnosis, and Management
COA) and is also a certi-fied provider of nursing continuing education in
California (provider number CEP3257). Mosby
recognizes this activity as continuing education
Department of Dermatology and Cutaneous Surgery
approves or endorses anyproduct included in the
This course is sponsored in service of the public health by:
HairClean™® 1-2-3LiceRemover The natural, non-chemical solution
754 Washington Street Eugene, Oregon 97401
Additional educational materials for nurses, familiesand students are available free of charge.
Fig 3. Viable head louse egg(lower left) andhatched empty egg(above).
louse nymph com-pared to a period atthe end of a sentence.
Fig 5. “Hair muff,” or artifact often mistaken
Physical DescriptionThe head louse is a bloodsucking, wingless insect with a hard
exoskeleton. Like all insects, it has three pairs of legs. Each leg
the participant should be able to:
ends in a claw with which the louse grasps the hair shaft. Antennaelocated in front of the eyes enable the louse to detect odor, humidity,
■ describe the head louse and its life cycle;
temperature, and, possibly, other information not yet known.
■ diagnose pediculosis capitis (infestation
Head lice tend to adapt their color to their surroundings. Therefore,lice found on dark-haired, dark-skinned individuals are darker
than those found on people with lighter skin and/or blonde hair.1
The exoskeleton of lice also darkens in color with increased tem-
perature and sunlight.1 Thus, lice in warmer climates tend to be
darker in color than those found in cooler regions.
An adult head louse is usually 2 to 3 mm long, or about the size of
a sesame seed. Females are generally longer and wider than males
■ describe the various courses of treatment
and have a more rounded abdomen (Fig. 1). The rear portion of
the female abdomen ends in two protrusions, or “gonopods,”
■ discuss head lice resistance to pediculicides
which form a V-shape the width of a human hair.1 The gonopods
are supportive structures that enable the female to clamp the hairshaft while laying eggs.
■ describe measures to prevent reinfestation;
■ educate teachers, parents, and children
Male lice have distinguishable brown bands across their backs
(Fig. 1). The rear portion of the male exoskeleton is rounded andtilts upward, with the anal and sexual organs located on the louse’s
■ conduct a school-wide head lice screening.
back. This arrangement enables the male louse to crawl beneaththe female for the purpose of copulation.
Twenty-four hours after mating, the female head louse lays her
Pediculosis, the infestation of humans by lice, has been document-
eggs, more commonly referred to as “nits.” Under optimum condi-
ed for thousands of years. Head lice and nits have been found on
tions, a healthy female will lay approximately 140 eggs during her
human mummies, and lice are mentioned in ancient writings,
lifetime of about 30 days. The eggs are coated with a fixative that
including the Bible. Not all civilizations have viewed these para-
cements them to the hair shaft (see Fig. 2). Because the chemical
sites in a negative light. The Aztecs, for example, collected their
structure of this fixative substance is very similar to that of the hair
lice in bags and offered them to their emperor as a token of
shaft, researchers have yet to develop a product that will dissolve
respect. Young women in northern Siberia once threw lice at men
as a sign of affection, as if to say, “My louse is thy louse.”1
The location of the nits on the hair shaft may vary depending on
Today, most westernized societies consider lice undesirable and
climate and temperature. Because nits are incubated by human
expend billions of dollars on head lice treatment and control.
body heat, it is commonly thought that most eggs are laid close to
Despite the efforts of parents, health providers, and school authori-
the scalp and that the distance of a nit from the scalp may be used
ties, however, infestation with head lice is a persistent and growing
to judge the nit’s viability. In warm climates, however, the top of
problem. Head lice affect up to 25% of school-aged children in the
the head is often too warm for optimal incubation, and viable nits
United States,2 and incidence appears to be on the rise, with lice
may be found 6 or more inches down the hair shaft.3
becoming increasingly resistant to many commonly-used pediculi-cide products.3
Newly-laid, viable eggs are plump and shiny and have a tan or coffee color. Eggs that have hatched are clear, white, or light in
color and may appear shrunken or indented (Fig. 3). On the end
The head louse, Pediculus capitis, is one of three species of lice that
of the nit facing away from the scalp is the “operculum,” a tiny
infest humans. The other two are Pediculus humanus, the body or
cap with several holes in it that allow air and moisture into the egg
clothing louse, and Pthirus pubis, the pubic or “crab” louse.
Unfortunately, body lice, which are associated with poor hygiene,have given all lice a bad reputation. Body lice live on clothing and
After a 7- to 10-day incubation period, the baby louse, commonly
go to the body only to feed. Therefore, they are most commonly
referred to as a “nymph” or “instar,” uses its mouth parts to cut a
found among refugees, victims of disaster or war, homeless individ-
hole in the operculum. The nymph then sucks in air and rapidly
uals, and others who are unable to wash or change their clothes.
expels it, causing the operculum to pop off. The newly-emerged
Head lice, in contrast, spend their entire lives on the human scalp,
nymph closely resembles an adult louse but is much smaller and
clinging to the hair while feeding, mating, and laying eggs. They
not yet capable of reproducing. It is flesh-colored and no larger
are not linked to poor living conditions and are most commonly
than a pinhead, making it almost impossible to see with the naked
found in individuals with good hygiene and grooming habits.
eye (Fig. 4). The nymph emerges from the egg active and mobile
and must feed on human blood shortly after hatching, or it will
bites, the infested individual may be feverish and feel tired and irri-
rapidly succumb to dehydration and starvation.
table due to lack of sleep, hence the term “feeling lousy.”
The nymph goes through three stages of development, or “instar
Although the body louse is notorious as a carrier of typhus,
stages.” Each instar stage lasts 3 to 4 days and terminates when
research has not shown the head louse to be a vector of serious
the nymph molts, casting off its exoskeleton to reveal a new one.
disease. Some head louse professionals believe, however, that the
The sex is not determined until the final molt, which occurs any-
head louse has not been studied long enough or closely enough to
where from 9 to 12 days after hatching. At this point, the louse is
rule out its potential for transmitting typhus and other louse-borne
a full-sized sexually-mature adult. The adult female must take a
diseases. Head lice have been shown to transmit Staphylococcus
blood meal before copulating, and her first eggs are laid within
aureus and Group A Streptococcus pyogenes,1 resulting in infec-
tions of the scalp. Chronic scalp infections are not uncommon inindividuals with active head lice infestations, especially in tropical
Unlike many ectoparasites (external parasites) that can endure star-
climates or when daily hygiene is difficult to maintain.
vation and extremes of temperature, lice and their eggs can surviveonly under a relatively narrow set of environmental conditions.
From their first blood meal to their last, lice prefer to feed every
The definitive diagnosis of head lice infestation occurs when a live
4 to 6 hours and cannot survive if they miss several consecutive
louse or viable egg is found on the scalp or hair. The scalp should
meals. Also, lice require a temperature of 87°F (30.6°C) to 95°F
be examined in sunlight or under bright artificial light (e.g., fluo-
(35°C) for continued survival, and prolonged temperatures below
rescent light). The hair should be parted, with individual strands
65°F (18°C) or above 97°F (38°C) are fatal to the egg. Therefore,
checked for nits. Magnifying reading glasses (2x or greater) avail-
although a louse may fall or climb onto other surfaces, it cannot
able in pharmacies can aid in visual detection.
live on these and must return to a human head within 24 hours ifit is to survive.
Because lice are fast, avoid light, and often blend in with the skinor hair, making them difficult to see, finding nits is the most effec-
tive way of diagnosing an infestation. Nits are most predictablyfound on hairs at the nape of the neck and behind the ears, where
they are protected from extremes of light and temperature. However,
they may be laid anywhere on the hair (see Fig. 2), especially in
warm weather, and the entire head should be examined. Viable nits
can be distinguished from non-viable nits with the use of a 10x
hand-held magnifier. Because the light-colored non-viable nits are
often more noticeable than “camouflaged” viable nits, it is not
uncommon to find more nits a day or two after treatment than
The appearance of a nit is often confused with that of a flake ofdandruff or a dried particle of hairspray or gel. A distinguishingfeature is that dandruff and hair products can be easily combed off
the hair or removed with the fingers, while nits cannot. Nits are
firmly glued to the hair and must be removed with a fine-toothedcomb or fingernails, or snipped off with a scissors. Signs and symptoms Although the feeding bite of the louse is painless, louse saliva
Another artifact commonly mistaken for an egg is the “hair muff”
contains a vasodilator and an anticoagulant that cause an allergic
(Fig. 5). Without a good light and a magnifier, even an expert may
reaction in most individuals. The vasodilator causes the capillaries
mistake hair muffs for nits. Hair muffs consist of dried skin cells
to expand, while the anticoagulant prevents clotting of the blood,
(desquamated epithelial cells, or dec) and oil from the hair follicle
producing red marks and itching at the site of the bite. The severity
that surrounds the hair shaft, creating the illusion of a nit. They
of the host reaction depends on host sensitivity and the number
are especially common in individuals who have been treated many
of prior exposures. Initial infestation may produce no signs or
times with pediculicides, which may dry the scalp and clog the
symptoms for 4 to 6 weeks. Subsequent infestations may produce
sebaceous glands. Schoolchildren are often mistakenly sent home
itching within 24 to 48 hours. Therefore, first-time infestations are
with this condition and then retreated with pediculicides, creating
often asymptomatic, and severe itching usually indicates an infesta-
tion that has been present for several weeks. Some individuals canremain asymptomatic and never itch; these individuals can be con-
Finally, although individual feeding sites may be difficult to see,
sidered “carriers.” The existence of asymptomatic head lice carriers
red marks, scratches, scaling, rash, and sores, including pyodermas,
may account for the high rate of reinfestation among individuals
may be present in infested individuals. These symptoms should be
distinguished from contact or seborrheic dermatitis, insect bites,eczema, psoriasis, and piedra (a harmless fungal infection of the
Intense itching at the site of the bite compels the host to scratch,
hair), all of which can give a false-positive diagnosis for pediculo-
often breaking the skin. The open scratches, in turn, create an
sis. Also, repeated treatment with pediculicides can in itself cause
entryway for germs and lice feces and may lead to secondary infec-
irritation to the scalp with scaling, rash, and itching. These side-
tions and swollen glands in the neck. With a large number of lice
effects should not be confused with signs of an active infestation.
Most pediculicide products currently available in the US kill lice
Essentially everyone with hair on his or her scalp is susceptible to
but do not kill all eggs. Therefore, all topical pediculicides should
head lice infestation. Some groups, however, are more susceptible
be applied two times, one week apart. The second application is
than others. The group most likely to get head lice is children aged
necessary to kill any nymphs that may have hatched from eggs
3 to 11 years.1,4,5 The relatively high incidence of head lice in this
group is probably related to head-to-head and body contact duringplay and the sharing of objects to which lice can cling, e.g., combs,
There has been a continuing struggle to find new pediculicidal
brushes, hats, barrettes, helmets, head phones, and other head gear.
agents ever since head lice developed resistance to DDT in Englandin 1949. In the past, it seemed as though investigators were always
Most studies, including those conducted in the United States, show
one step ahead of the louse with a new treatment, but now it
that infestations are more common in girls than in boys, but others
appears that lice are developing resistance to lice-killing products
show no association between infestation and gender.3 In most cul-
faster than new ones are being developed. The active ingredients of
tures, girls tend to have longer hair than boys. This may account
the pediculicidal products currently available in the United States
for the gender differences in some studies; researchers in Israel
include lindane, malathion, natural pyrethrins, and permethrin.
found that children with long and medium-length hair were more
These and other alternative head lice treatments are discussed in
likely to be infested than children with short hair.6 Also, girls may
be more likely than boys to share brushes, combs, and hair acces-sories. Length, texture, and color of the hair and gender of the host
Regardless of the pediculicidal product used, it is important to
have not been shown to be significant factors in host preference.1
stress to the patient or parent that pediculicides are insecticides andshould be used according to instructions. To ensure that there are
Head lice can infest all levels of society and most racial and ethnic
no language, hearing, or reading problems, it is always advisable
groups. They can be found on the heads of whites, Asians,
to have the patient repeat the instructions verbally. Also, because
Hispanics, and North, Central and South American Indians. Race
several pediculicide products decrease in efficacy after being
has been shown to be a factor in infestation in only one instance—
opened, pediculicides should be discarded after the second treat-
head lice are so uncommon among African Americans that it is
ment. They should never be stored in a medicine cabinet, where
recommended that this group be excluded when estimating preva-
they may be confused with cough syrup or other medications
lence.1,7 It is believed that the head louse indigenous to this part
several months after the infestation.
of the world is not well adapted to grip the oval-shaped hair shaft characteristic of the hair found in the black population.
Nevertheless, cases of North American head lice in blacks (e.g.,African Americans, Jamaicans, Haitians) occasionally do occur
Currently, lindane is one of two prescription products that havebeen approved by the Food and Drug Administration (FDA) for
the treatment of pediculosis (the other, 0.5% malathion, is dis-
Because lice are very host-specific, the lice that affect humans can-
cussed below). Lindane is in the class of chemical insecticides
not be transmitted to or from pets or other animals. Head lice are
called organochlorines, which also includes DDT. It has been avail-
transmitted from person to person, either directly or indirectly.
able as a 1% shampoo for the treatment of head lice and a 1%lotion for the treatment of scabies for more than 50 years. The
Direct transmission may occur during children’s play or other
lotion is FDA-approved for scabies only and is potentially toxic if
activities in which individuals come into close physical contact with
each other. Contrary to common belief, lice cannot jump (like fleas) or fly (like gnats). However, head lice that are warm and well-fed
Lindane shampoo has a short application time (4 minutes) and is
can move fairly quickly from hair to hair and scalp to scalp.
relatively easy to use, but it also has some significant drawbacks. First, lindane may be stored in human tissue and will accumulate
Indirect transmission may occur through contact with lice-carrying
in the body with repeated use.8 If overused, misused, or accidental-
objects. Lice may cling to a long list of objects, including brushes,
ly ingested, lindane may be toxic to the central nervous system.
combs, hats, clothing, costumes, athletic gear, and towels.
Clinical symptoms of central nervous system toxicity relating to
Although lice cannot survive for long on such objects, they can
lindane poisoning may include: nausea, vomiting, headache, dizzi-
move readily from them to another scalp. Thus, it is not uncom-
ness, restlessness or hyperactive behavior, apprehension, tremors,
mon to trace an outbreak of head lice to a single, shared object,
weakness, increased excitability, disorientation, convulsions, respi-
such as a batting helmet or a set of language lab headphones.
ratory failure, twitching of eyelids, coma, and occasionally death.8Lindane overuse also may result in “delusions of parasitosis,” or
the mistaken belief that one is infested with parasites. Delusions of
Common measures to mechanically remove lice and nits from the
parasitosis often arise from altered neurological sensations, which
hair, such as brushing, combing with a good nit comb, shampoo-
patients have described as a sharp sting or pain, increased itching,
ing, and towel- or blow-drying, play a role in reducing the number
or a “biting” or “crawling” sensation. Although these feelings are
of viable lice and eggs on the head, but are insufficient to cure an
real to the patient, they are not due to a continued infestation, but
active infestation. Effective treatment involves the application of
are instead manifestations of lindane toxicity. Believing that they
a pediculicide to kill lice and nits followed by manual nit removal
are infested with “bugs,” patients experiencing these sensations
may use lindane repeatedly, thus creating a dangerous cycle.3,9Due to its potential for toxicity, lindane should not be left on for
longer than the prescribed time and should not be used more than
two times one week apart. Prescriptions should not be refilled.
Ivermectin is perhaps best known as a safe and effective treatmentfor onchocerciasis, or “river blindness” caused by the parasitic
Another major drawback of lindane is its relatively poor pediculi-
worm Onchocerca volvulus. A single oral dose of 150 to 200 µg/kg
cidal and ovicidal (nit-killing) activity. Because lindane resistance
body weight given semiannually in a 6 mg tablet is effective against
in lice has developed in the US and other countries,3 lindane has
this disfiguring and blinding disease. Worldwide, an estimated 18
a relatively high treatment failure rate, compared with several
million children and adults are treated with ivermectin each year.
over-the-counter (OTC) pyrethrin and permethrin products (see“Pyrethrins” and “Permethrin” below). Moreover, even in non-
In the early 1990s, anecdotal reports that ivermectin resolved
resistant lice, lindane is a slow-killing pesticide. Lice exposed to
ectoparasitic infections in patients with onchocerciasis prompted
lindane 1% shampoo may take many hours to die,10 during which
studies of the effectiveness of this drug for the treatment of scabies
time they shake and squirm, often causing increased itching and
and head lice. In studies using ivermectin against onchocerciasis,
individuals who had received ivermectin tended to have significantlyfewer head lice than individuals who had not received this drug.12
Finally, lindane 1% shampoo leaves the hair with a straw-like texture that makes it almost impossible to comb out, even with
While the FDA has approved ivermectin for the treatment of
a wide-toothed comb. The use of a non-pesticide creme rinse or
onchocerciasis and strongyloides, another internal parasitic infec-
detangler may facilitate nit removal following lindane use. Other-
tion, this drug does not have an FDA-approved indication for the
wise, it is a tedious and painful experience for both parent and child.
treatment of head lice. However, ivermectin has been used “offlabel” for pediculosis treatment when all other treatments have
In view of the many negative aspects of this pediculicide, it is difficult
failed. A public health official in the US prescribed this treatment
to see the advantage of future lindane use, particularly because sev-
for pediculosis when grade schools in parts of Washington state
eral other equally-effective and less-toxic treatments are available.1
were closed due to outbreaks of “resistant head lice.” Ivermectin
If the patient or parent prefers a prescription product for financial
delivered orally at 200 µg/kg seemed to cure most individuals, but
reasons, 0.5% malathion lotion, ivermectin, or 5% permethrin
follow-up was difficult, and some people required a second dose
cream (discussed below) are safer and more efficacious options.
the next day to kill surviving lice.13 Clinical trials are necessary todetermine the optimum dose.
MalathionAlcoholic 0.5% malathion lotion was approved by the FDA
Products Available Over the Counter (OTC)
around 20 years ago, but has been marketed in the US only inter-mittently. In 1999 it became available by prescription under the
brand name Ovide® (Medicis, Scottsdale, AZ). Ovide® is the
The flower heads of Chrysanthemum cinerariaefolium (pyrethrum)
quickest-acting and most ovicidal of any pediculicide developed in
yield a mixture of natural botanical extracts called pyrethrins.1
the last 30 years.1,10 Ironically, despite its quick action, this prod-
These pyrethrins, which have insecticidal properties, have been
uct has a relatively long recommended application time. Because
formulated into various lotions, shampoos, foam mousses, and
the original malathion studies for FDA approval involved an 8 to
gels for the treatment of head lice. Trade names include RID®
12 hour application, this became the recommended treatment pro-
(Bayer, Leverkusen, Germany), A-200® (Hogil, Purchase, NY),
tocol. There is evidence, however, that Ovide® is highly effective
Clear Lice System® (Care Technologies, Darien, CT), and Pronto®
against lice and nits in less than 10 minutes.10 Clinical trials should
(Del Laboratories, Uniondale, NY). Generic pyrethrin products
be conducted to establish the optimum application time.
The high content of isopropyl alcohol (78%), pine needle oil, and
Most pyrethrin products combine natural pyrethrins with piper-
turpineol in this product make it quite flammable, if accidentally
onyl butoxide (PBO), which has insecticidal properties of its own.1
ignited. Furthermore, the odor is quite objectionable, and inhaling
PBO is a synergist that greatly enhances the activity of pyrethrins
the fumes can result in headaches when the product is applied for
and seems to play a role in preventing or slowing down the devel-
the recommended 8 to 12 hours. A 10-minute application does not
Natural pyrethrins demonstrate low toxicity in mammals. However,
Illnesses linked to agricultural use of malathion have raised con-
the active components in pyrethrin pediculicides are extracted with
cerns about its toxicity in humans. However, the high grade of
kerosene or petroleum distillates that may cause eye or scalp irrita-
malathion used for the treatment of human pediculosis is very dif-
tion.1 Also, because pyrethrins are natural botanical extracts, all
ferent from the grade used for agricultural or veterinary purposes.
pyrethrin products carry a warning of possible allergic reaction in
Based on extensive toxicity studies for an 8 to 12 hour application
patients who are sensitive to ragweed or flowers, but these reac-
time, the FDA has approved 0.5% malathion alcoholic lotion for
pediculosis treatment, and this product is believed to be safe whenused as directed.
Natural pyrethrin products suffer from instability to heat and light,and they have no residual activity once they have been rinsed off.
Malathion resistance in head lice has been documented in England,11
Furthermore, none of the natural pyrethrin pediculicides are totally
but so far, there are no documented cases of resistance in the
ovicidal.10 Twenty to 80% of the nits remain viable after treatment.
United States. Lice in the US may have remained sensitive to
Therefore, a second treatment is necessary 7 to 10 days after the
malathion because this product is not as readily available here
as it is in the UK, where it can be purchased over the counter.
Although there is no published documentation of pyrethrin resis-tance in the United States, recently there has been an increase in
reports of treatment failures. Further research is necessary to
determine whether these reports represent cases of resistant lice.
Because outbreaks of pediculosis frequently occur in the summer
months, when the temperature is warm and children come
By synthesizing and modifying the molecular structure of natural
together at camps and sleepovers, a schoolwide screening for
pyrethrins, chemists were able to develop compounds called
pediculosis should be held soon after school starts in the fall.
synthetic pyrethroids. Permethrin, one of the first heat- and light-
A second screening is recommended in mid-January, when chil-
stable synthetic pyrethroids, is highly toxic to insects and other
dren are returning from holiday vacation. The following plan
arthropods but is one of the least toxic insecticides to mammals.8
can maximize the efficiency of the screening process.
Based on oral studies in animals, permethrin is about 3 times less
toxic than natural pyrethrins and approximately 36 times less toxic
■ Obtain permission for the screening from the school administrator.
■ Arrange for one trained volunteer per 200 students to help with
Permethrin is available by prescription as a 5% cream (Elimite®,
■ Gather supplies, including a fluorescent lamp, a 10x hand-held
Allergan, Irvine, CA; Acticin®, Penederm, Foster City, CA) or over
magnifier, screening sticks to part the hair, and disposable gloves.
the counter as a 1% crème rinse with the trademark Nix® (Pfizer,
Disposable gloves should be used to maintain proper hygiene
NY, NY). The 5% permethrin cream, commonly prescribed for the
treatment of scabies, does not have an FDA-approved indication
for the treatment of head lice but is recommended by some doctors
■ Prepare and send a letter signed by the school nurse and admin-
because it is safe for an 8 to 14 hour application in children as
istrator to the parents informing them of the date and time of
young as 2 months. The 1% permethrin crème rinse Nix® has
the upcoming screening. Include suggestions that will help par-
been approved by the FDA for the treatment of pediculosis since
ents check their children and the surrounding household for
1986. This product has undergone more clinical trials and toxicol-
signs of lice and nits. Offer suggestions for treatment.
ogy studies than any other pediculicide on the US market.
Like the natural pyrethrin products, Nix® is not completely ovici-
■ Provide teachers with a schedule that includes the date and time
dal; approximately 20% to 40% of viable eggs hatch after treat-
■ Encourage teachers to discuss the upcoming screening with their
ment. Also, although residual permethrin on the hair once killed
nymphs soon after they hatched, this is no longer the case. Thedecrease in the residual activity of Nix® suggests that permethrin
levels that were lethal in the past may be sublethal today.
■ Beginning with the youngest class, have each class line up in
Since 1994, it has become clear that permethrin is no longer as
■ On the roster, indicate which children are infested. Use one nota-
effective as it had been previously. Data from researchers in
tion for children who have viable lice and nits and another nota-
England, France, the Czech Republic, and Israel show that head
tion for those who have nothing but hatched, non-viable nits.
lice have become resistant to permethrin.3 Recent studies in the US
■ At the end of the day, have the teacher gather the students that
have not only confirmed the existence of permethrin resistance,14
are infested. Hand each student involved an envelope with a let-ter and suggestions to the parent for treatment of the child.
but also traced this resistance to specific genetic mutations in lice.15
■ Children with viable lice and nits should be given a letter recom-
mending treatment with a pediculicide followed by combing to
HairClean 1-2-3® (Quantum, Eugene OR), an FDA-approved lice
■ Children with nothing but hatched, non-viable nits should be
removal system consisting of a hair hygiene treatment and a nit
given a letter recommending combing to remove the nit casings.
comb, is available in drug and health food stores. This product con-
■ Have trained, designated volunteers contact parents by phone to
tains no chemical pesticides, making it an attractive alternative for
ensure proper treatment and answer any questions they may
individuals who are opposed to using chemical products on the head.
have. Many parents will be angry about the situation. Such
The hair hygiene treatment consists of all natural ingredients, includ-
anger most likely represents underlying embarrassment or guilt.
ing anise oil, ylang ylang oil, coconut oil, and isopropyl alcohol.
Therefore, head lice should always be discussed with a con-cerned but unemotional attitude, the way a head cold or fever
In studies conducted in South Florida, HairClean 1-2-3® appeared
might be discussed. An attitude of calm, professional concern,
to be a safe and highly-effective pediculicide. HairClean 1-2-3®
sympathy, and reassurance will do much to defuse feelings of
killed all lice and nits in 98% (51/52) of study participants. By
comparison, Nix® showed a treatment success rate of 89%
(17/19). No adverse experiences were reported.3
■ Make sure each teacher and parent clearly understands that
infested children are not to re-enter the classroom without
There are no known reports of resistance to HairClean 1-2-3®,
a visit to the health office for a clearance by a school nurse.
making this product a viable alternative in cases of resistant lice.
■ Schedule a trained and designated volunteer to be available for
Also, because the hair hygiene treatment prompts lice to leave the
the next two days to help examine returning children and pro-
scalp and run to the tips of the hair, use of this product may aid
vide any additional support required for families still infested.
ing nits, the possible psychological damage done by such shearing
Reluctant to continue applying pesticides to children’s heads, many
desperate and frustrated parents and health professionals are turn-ing to alternative therapies to battle head lice. Many individuals
claim to have successfully cured their infestations by using inexpen-
sive, non-pesticide products including petroleum jelly, hair pomade,
After individual treatment, the second step in pediculosis control
olive oil, mayonnaise, vegetable shortening, vinegar, mineral oil,
is to treat other individuals to whom lice may have spread. All
and essential oils sold at health food stores.
household members should be checked for lice and nits—adults
There is no doubt that oily alternatives such as petroleum jelly,
as well as children. Additionally, anyone with whom the infested
olive oil, or mayonnaise slow down the lice, making them easier to
individual has recently had physical contact or possibly shared lice-
find and comb out, and even killing some. Unfortunately, because
carrying objects should be checked. This may include classmates,
they are not as effective as the currently available pediculicide
playmates, and babysitters in the case of children; and co-workers
products, they usually require repeated overnight treatments and
and acquaintances in the case of adults. If these individuals are
many hours of painstaking combing. The need for repeated
found to have lice or nits, their families and friends should in turn
overnight treatments, in turn, can delay a child’s return to school.
be notified, and so on. It is only by attempting to eliminate theentire chain of transmission that the cycle of infestation and rein-
It is common practice to comb or “nit pick” through the hair aftertreatment to remove lice and nits. Nit removal is important for
two main reasons. First, it removes an outwardly visible sign of
The third step in controlling pediculosis and preventing reinfesta-
head lice infestation, thus preventing stigmatization. Second,
tion is to thoroughly clean all objects of potential transmission.
because no pediculicide product kills 100% of eggs, manual nit
In order to remove all lice and nits from the environment, the
removal is recommended to eliminate any nits that may have sur-
■ All clothing, bedding, and linens that the infested individual may
Many school officials insist on a “no nit” policy to ensure freedom
have worn or handled within two days of diagnosis should bewashed in hot water (150°F) and dried on “high” for 20 minutes.
from infestation and proof of adequate treatment. Because this policy fails to differentiate between viable and non-viable nits, it
■ Brushes, combs, and hair accessories should be soaked in either
tends to have an overreaching effect, keeping children who pose
rubbing alcohol or hot (150°F) soapy water.
no threat of transmitting lice from attending school. The “no nit”
policy also places a substantial burden on parents, who must go
through the time-consuming process of removing all nits from the
hair. For many working parents, this may mean missing consider-
permethrin vs. lindane for the treatment of scabies [editorial]. Arch Dermatol
Team, University of Miami, FL) for her editorial assistance and Lidia Serrano (Lice
Source Services, Plantation, FL) and Kathy
Combing the hair with a wide-toothed comb does not suffice for
nit removal. Nit removal is a slow and careful process of examin-
ing individual hairs from root to tip and completely removing all
nits with a special fine-toothed comb. The process is made easier
Eberle MW. Comparative efficacy of treat-
ments for pediculosis capitis infestations.
when the hair is parted and combed in sections, and use of a
detangler or hair conditioner may facilitate combing. Plastic nit
11. Downs AM, Stafford KA, Coles GC.
combs that come with pediculicide products often are not as
and insecticide resistance. Parasitol Today
good as metal combs purchased separately. Both the LiceMeister®
available in the United States through the National Pediculosis
2. Friedlander SF. What’s new in cutaneous
infection? Presented at the Second Annual
Association, and the Quantum Lice Comb (Quantum, Eugene, OR)
JAG. A field study of the effects of iver-
Infectious Diseases in Children Symposium
seem to work well. The Quantum Lice Comb is particularly easy
to grasp and manipulate and is less expensive than the LiceMeister.
13. Brettman A. Untested pill kills lice fast,
dozens of local parents say. The Daily
Because eggs scraped off the hair are caught in the teeth of the nit
News (Longview, WA) 1997 Jul 10.
comb, the comb should be treated or discarded after use. An old
14. Pollack RJ, Kiszewski A, Armstrong P,
CN. Ectoparasitic diseases in dermatology:
toothbrush or dental floss can be used to dislodge the nits. Metal-
reassessment of scabies and pediculosis.
toothed combs should be soaked in rubbing alcohol or pediculi-
Advances in Dermatol 1999;15:67-108.
Differential permethrin susceptibility of
cide. Plastic combs should be sealed in plastic and thrown away.
5. Mumcuoglu KY, Klaus S, Kafka D, et al.
head lice sampled in the United States and
Clinical observation related to head lice
Following treatment and manual nit-removal, the infested individ-
ual should be checked for lice and nits daily for 14 days to ensure
6. Mumcuoglu KY, Miller J, Gofin R, et al.
that he or she has not become reinfested. It is not necessary to
Epidemiological studies on head lice infesta- Devonshire AL, Clark JM. Moleculartion in Israel, I: parasitological examination
analysis of kdr-like resistance in perme-
cut long hair or shave the head to manage a head lice infestation.
of children. Intl J Dermatol, 1990;29:502-06.
thrin-resistant strains of head lice, Pediculus
While such measures may ease the task of looking for and remov-
capitis. Pesticide Biochem & Physiol
tations and insect bites. New York: MarcelDekker; 1985.
■ Carpets, rugs, and upholstered furniture should be thoroughly
vacuumed, and the vacuum bag should be carefully removed
No single approach is likely to be effective in eradicating head lice.
Due to the development of lice that are resistant to many existingpediculicides, infestations are increasingly difficult to treat.
■ Spraying classrooms or homes with insecticides is not recom-
mended for cases of head louse infestation. In fact, it is strongly
Moreover, while currently available pediculicides kill lice with
discouraged by many health professionals, including those at the
varying degrees of success, none of these products kills all eggs.
National Pediculosis Association and the Centers for Disease
Therefore, treatment with pediculicides is an imperfect solution to
Control. Because washing and vacuuming are adequate protection
the head lice problem and should be accompanied by preventive
if done properly, the potential health risk of spraying or fumiga-
efforts. Preventing the transmission of head lice involves not only
tion is unwarranted. Also, insecticides intended for veterinarian
treating infested individuals, but also eliminating lice from the
or agricultural use should never be used on people or on house-
environment, raising the awareness of school officials and health
hold objects such as furniture or stuffed animals.
professionals, and, most importantly, educating children and their
■ In taking measures to avoid reinfestation, it is helpful to recall
parents about head lice infestations and their control. ■
that head lice cannot live more than 24 hours off the host at normal room temperature or higher. Eggs attached to hairs may
This course is based on an article by the author that originally appeared in Current Problemsin Dermatology, 1999;11 1999 Mosby, Inc.
remain viable for up to 10 days after treatment, but the nymphmust find a blood meal within hours of hatching, or it will die.
c) lindane is not as effective as several
5. In the United States, head lice infesta-
tions are least common among:
2. Viable eggs differ from eggs that have
a) a viable egg has a tan to coffee color,
comb after treatment with a pediculicide:
3. Which of the following is not a poten-
or symptom of infestation with head lice?
Department of Continuing Education & Training Mosby, Inc. 11830 Westline Industrial Dr. St. Louis, MO 63146 800-325-4177
Sponsored by HairClean 1-2-3 Lice RemoverQuantum, Inc. 1-877-LICE-877 (1-877-542-3877) www.quantumhealth.com