Posted at www.headlice.org with permission from the American Journal of
Pharmaceutical Education - 8/4/99.
Head Lice: Perfectly Adapted Human Predators
W. Steven Pray
Lice and their treatment are presented to students
in the third professional year as a portion of a 4-hour required
course in Nonprescription Products and Devices. Taught three
times yearly, the course uses the textbook "Nonprescription
The section on head lice occupies approximately
90 minutes, and is supplemented by several learning interventions.
Students view slides supplied by the Centers for Disease Control
illustrating head lice, nits and nymphs. The instructor also
passes dead head lice around the classroom to facilitate the
student's recognition of the pest in regard to size and color.
Finally, as students enter class, they are asked to look into a
microscope set to 10X with a slide of nits attached to a hair.
When available, the instructor prefers to use viable nits to
allow visualization of the nymph's heartbeat. Occasionally,
students may witness the emergence of the nymph from the egg case.
The fear of being preyed upon is nearly universal in
human beings. Various phobias exist to such intentional or
accidental predators as sharks, spider, snakes, scorpions, tigers
and bears. In this section of the dermatology lectures we explore
just such a predator, a parasite which must obtain regular meals
of human blood to exist.
Stories of obligate human parasites are decades
old, with the most well-known being the vampire mythos. Dracula
was written to be a horrifying story, but at least after he drank
the victim's blood, he flew out the window. We are now covering
the head louse, another blood-sucking human predator, but there
is an important difference: head lice do not willfully leave the
host. These creatures have a perfect existence, eating and
defecating on your head, meeting members of the opposite sex,
copulating, and laying eggs on your hair. They are referred to by
some as "mechanized dandruff."
This is not a glamorous topic. In other
therapeutics courses you are able to cover the more compelling
human conditions, such as diabetes mellitus, renal failure, and
hepatic encephalopathy. However, throughout this nonprescription
products course we have studied the "minor" medical
conditions which many clinicians simply do not have sufficient
time to cover (e.g., hemorrhoids, gingivitis, motion
sickness, and dandruff). However, for the sufferer they are
obviously important, as sales of products marketed to treat them
continue to grow. Some of these conditions are also extremely
embarrassing. For this reason, the pharmacist must exercise great
tact when counseling patients who require assistance.
THE HEAD LOUSE
General Information. There are three types of
human lice, each perfectly evolved for its ecological niche. The
most common is the head louse, Pediculus humanus, var. capitis.
The second most common type, the crab louse (Phthirus pubis)
is placed into a separate genus(1). The least common type of
human louse in the U.S. is the body louse, Pediculus humanus,
var. humanus or corporis (both terms have been used),
which is very similar to the head louse, differing mainly in its
living preferences and some minor anatomic features. Whereas the
head louse lives on the head and lays its eggs on the hair shaft,
the body louse lays its eggs in clothing that is worn for many
days without being washed, while obtaining blood meals from the
person wearing the clothing. Unless specifically mentioned, all
of the remaining comments will refer to the most common type of
human louse, the head louse.
Paleontologists have yet to locate fossilized
head lice, but there is a rich historical lore surrounding lice,
nonetheless. Archeologists are quite familiar with lice, having
excavated mummies with lice, ancient combs with nits, and records
indicating that Egyptian priests shaved the heads to treat head
lice(2). Examination of ancient lice reveals that they are
identical to the present-day predators.
Head lice belong to the order Phthiraptera,
and to the group Anoplura. These insects have no wings,
nor can they jump. The pharmacist counseling a patient with head
lice does not have to fear that the lice will fly over or jump
onto the pharmacist like a grasshopper. Their method of movement
relies on six legs, each of which terminates in a claw that is
easily able to grasp human hair. Using claws alone, lice can
crawl through hair at an astounding 12 inches per minute, no mean
feat for an insect that is only 2-4 millimeters in length(2).
The head louse found on humans is a human
parasite only, and cannot be contracted from the family dog, cat,
or any other animal. While other mammals and birds do indeed have
lice, they are species-specific, so much so that they are placed
in different groups, families, or genera(3).
The Life Cycle. The female head louse
lives for about 17-22 days, laying about 10 eggs daily, so she
could potentially infest the human with approximately 200 eggs,
assuming she locates a sexually mature male whenever
fertilization is required(1). She lays eggs (known as nits) on
the hair shaft itself, in the closest proximity possible to the
scalp in most cases, at the skin-hair shaft junction. She
attaches the egg to the hair with an extremely strong cement that
allows the nit to remain tightly affixed despite regular combing
and washing. Each oval egg is composed of a waxy material that
protects the maturing larva, with a perforated top to allow
respiration. The larva normally matures to its birth time in 6-9
days, using the body heat radiating from the host's scalp as an
incubator(4). When it is ready to exit the egg case, the immature
insect begins to swallow air, expelling it rectally. This forms
an expanding bubble which pushes the insect through the top of
the egg to the outside. This insect truly flatulates its way to
life. Following its birth, the nymph must obtain a blood meal
from the host within 24 hours or it will not survive. After birth,
the nymph matures sexually in 7-10 days, meets a louse of the
opposite sex and begins the life cycle anew.
EPIDEMIOLOGY OF HEAD LOUSE
In order to delineate the population groups most
likely to contract head lice infestation, we need to first look
at the methods by which they are transmitted to patients. A
primary method of transmission is host-to-host, usually direct
head-to-head contact. For instance, suppose an uninfested child
is sleeping with an infested child (such as a sibling or a friend)
during a sleepover. If the hair of the infested child contacts
the hair of the uninfested child, the lice have a handy hair
bridge that is approximately body temperature to facilitate
colonization of the unsuspecting new victim.
The mode of transmission is often less direct.
Perhaps children's coats are kept in a pile or on adjacent hooks
at school or daycare. Lice on the infested child's coat can crawl
onto another coat. Then, they will enter the new child's scalp
when the coat is worn. Similar fomite-to-person spread is seen
when items are shared by successive individuals, such as baseball
helmets, computer headphones, portable CD player headphones.
Wearing another person's hats, scarves, or using their combs,
brushes or other grooming aids may facilitate spread.
When the mode of transmission is one of these
less direct avenues, it is usually from contacting an item that
has very recently contacted the host's head. By contrast, lice
are seldom contracted through contact with parts of the
environment which are not in intimate contact with a head (e.g.,
tables, couches, chairs, rugs). Lice do not mount expeditions,
striking off to find new heads. Instead, since they are obligate
human parasites, they have evolved with the instinct to stay on
the human at all costs. Thus, the perception of one's entire
house being contaminated is mistaken. With the above transmission
methods in mind, those most likely to become infested with head
lice are patients with a family member or close friend who is
Age. The average person thinks of head
lice as a problem of childhood, and this is usually true, in that
the most common age infested is 6-11. These children are more
likely to engage in activities that allow prolonged head-to-head
contact, such as taking nap breaks during school. Of course, once
a family has an infested member, age is no longer a consideration
since families tend to have close contact with each other
regardless of age.
Gender. Females of all ages are more
prone to contract head lice than males. Young girls often enjoy
close-contact play, such as "dress-up" and grooming
each other and themselves. Boys, on the other hand, are
sociologically more inclined to play games that do not involve
close contact with other boys (chase games, hiding games, war
simulation). Even within the family, the mother is more likely to
provide reassurance and nurturing that may involve sustained
Race. All hair is not alike. The hair of
Caucasians, Orientals, and native Americans is round in cross
section, whereas those of African descent have hair that is oval
in cross-section. The lice that predominate in the U.S. are
thought to have arrived with the early Caucasian settlers. Having
evolved with their hosts, they are only able to grasp the rounded
hair with their claws(1). They cannot easily grip the oval hair
shaft. For this reason, Black children are rarely infested in the
U.S., although every other group is at high risk. Conversely,
African lice are evolved to grip the oval hair, so those with
rounded hair shafts are largely protected from infestation with
the native lice found in Africa, and African natives are at high
risk in their home country.
CONFIRMATION OF HEAD LOUSE
When a patient suspects head lice, what can the
pharmacist do to help confirm their presence? The most obvious
thing is to inspect the heads. The technique of checking heads is
not difficult, once the pharmacist is properly trained. I use it
in my practice and also in the mass screening programs which I
Confirmation via Combing. I have heard
students and other professionals speak about seeing heads that
are so heavily infested that the hair is literally crawling with
lice, even to the extent that the hair seems to move. However,
these patients are the exception. Rather, the pharmacist or other
examiner must conduct a painstaking search to confirm an
The pharmacist should expect to find few live
lice during an exam, perhaps no more than 5-10. United States
lice are tan in color, matching the background Caucasian skin (lice
found in Africa are darker, matching the predominant skin color
of its native residents). American lice can be compared to a
sesame seed in size and color, except your typical sesame seed is
not capable of locomotion. Head lice have receptors on their body
which sense movement of adjacent hairs. When the pharmacist parts
the hair, they scramble to safety in the nearest dense bundle of
hair, making them hard to see and even more difficult to capture.
When checking the head, there are several
specific steps that should be followed:
- Wear disposable gloves;
- Find a location with good light,
preferably direct sunlight. This may require seating both
the patient and examiner outdoors on a patio or the
pharmacy's back porch. If this is not available, a strong
lamp may be sufficient;
- If the examiner is far-sighted, has poor
vision or any other visual detail abnormality (e.g.,
amblyopia), a magnifying glass may be necessary;
- Remove tangles from the hair with a comb
- Divide the hair into sections, examining
each section individually and fastening it away from non-examined
hair when it is inspected;
- Grasp a one-inch section of hair and use a
lice comb to comb each hair section carefully and slowly
from the scalp outward to the end of the hair. Lice combs
traditionally sold for lice detection/removal are made of
a one-piece plastic or metal construction that hinders
their efficiency greatly. However, a recently introduced lice
comb is rapidly becoming the standard for lice detection
and removal. Known as the LiceMeister®,
it is made by embedding 32 stainless steel teeth in a
rigid plastic handle. The teeth are long and tapered, and
are set so close that combing removes virtually all lice,
both adults and nymphs, and virtually all nits. Thus,
this innovative device can both screen for the presence
of lice and remove them to halt an infestation(5).
- Dip the LiceMeister® into a
cup of water after each hair section is combed. If debris
(e.g., nits, builds up between the teeth of the
comb, use a toothbrush or dental floss to clean between
- Continue combing each section of hair
until all is thoroughly combed.
- If the exam is negative, caution the
parent or caregiver to screen each day, as long as lice
infestation is still possible or suspected.
Simple Visual Confirmation. If the
LiceMeister® is not available, the pharmacist may
still be able to detect head louse infestation, although it is
more difficult to inspect all of the hair. In this case, the
pharmacist should still use gloves, strong light and a magnifying
glass if necessary. The hair may be parted with wooden paddles
and inspected carefully. The efficiency of this method is far
lower than with combing.
When simple visual confirmation is sought, the
pharmacist should look for live lice, but also the oval-shaped
nits attached to the hair shaft. It is almost impossible to tell
visually which nits are still incubating eggs and which are
hatched, but there are several clues. Nits most likely to be
viable are those closest to the scalp. Hair grows about 0.35 mm
daily, so a nit which is located as far as 1 inch from the scalp
was probably laid as long as 2.6 more months ago. If this nit is
not empty, it is not viable in most cases, since its probable
residence time on the head exceeds the incubation period. As lice
themselves depend on frequent blood meals, they are most often
found next to the scalp, and this is where laid eggs have the
best chance of hatching since it is in closest proximity to human
body heat. However, there are exceptions. In some way, a gravid
female louse's behavior changes when she is in a warm climate,
where the ambient air is close to human body heat, or exceeds it.
In these cases, she may lay an egg anywhere along the human hair
shaft, since outside temperatures facilitate hatching. So it is
not enough to examine distance from the hair to determine
viability of a nit. One must also take the temperature of the
ambient air into account. On a cold Minnesota day, a nit located
two inches from the scalp would probably not be viable, but on a
warm Texas summer day, it might well be viable.
The appearance of the nit is also a clue to its
viability. A nit which still contains a viable or dead unhatched
louse appears darker and translucent, whereas an empty egg case
appears whiter, more dull, and more opaque. Since these judgments
are difficult at best with the naked eye, I confirm them with a
microscope when feasible. I ask the patient if I may examine
strands of hair with nits in situ and remove several for
later inspection, also taking a home or work phone number from
the patient. After a microscopic examination, I can call the
patient to provide instructions the following day. This final
step continues the requirements for providing pharmaceutical care
for head lice, by helping ensure that the patient is properly
Differentiate Pseudonits. When looking
for nits, the pharmacist must be alert to pseudonits which
resemble nits but which are not signs of louse infestation. A
pseudonit is any object found in the hair which can cause
diagnostic confusion. This wide range of residue can include
dandruff scales, dirt or small plant matter blown into the hair,
or flakes from hair spray or hair grooming aids. Generally, if
the matter can be easily flicked from the hair with the finger,
it is not a nit, since the glue used by the mother louse to
cement nits holds them tightly. An exception is an object known
as the desquamated epithelial cell plug, which is ejected from a
hair under certain conditions. It encircles the hair, and cannot
be easily removed. Again, a microscope will differentiate these
nonviable objects from nits.
Look for Lice Feces. Lice feces are dark
in color. They may fall into the inner collar of a shirt or
blouse, where they become lodged in the clothing. As the person
turns the head from side-to-side, body moisture spreads the feces
along the inner collar. The pharmacist may note these black
streaks as an indicator of louse infestation.
Ask About Additional Symptoms. The
patient affected with lice may scratch vigorously to remove them.
The pharmacist may notice open sores on the head where the
fingernails have penetrated the skin. If they become secondarily
infected with staph and/or strep, they are said to have undergone
"impetiginization." These lesions may be more or less
parallel in arrangement, caused by simultaneous penetration from
several scratching fingernails, a phenomenon known as "railroad
tracking." Occasionally, a patient is so heavily infested
with head lice that systemic symptoms occur. They include
enlarged posterior cervical lymph nodes, fever, anorexia,
enervation, and malaise. These patients should be referred to a
physician to evaluate the need for an antibiotic/antibacterial
PESTICIDE TREATMENT OF HEAD LOUSE
Treatment of head lice has changed radically in the
last decade, as we have gradually turned away from the pesticides
known as pediculicides. At that time, a trade named lindane
product (Kwell) was widely recommended, a prescription product
containing malathion (Ovide) was available, and the
nonprescription armamentarium which contained only synergized
pyrethrins had recently been expanded with the Rx-to-OTC switch
of the pesticide known as permethrin (Nix). Things looked rosy
for elimination of this ancient human predator. Unfortunately,
the bright promise of these treatments soured in the 90s as the
topical pesticides began to lose their luster. What is the
current status of the pesticides?
Lindane. Lindane is a cyclodiene
pesticide which is also the most toxic pediculicide available(6).
It kills very slowly; as the lice die they twitch on the scalp,
producing an uncomfortable sensation for the patient.
Lindane has several other attributes that argue
against its use. It does not kill all ova (its ovicidal activity
is only 45-70 percent), allowing viable ova to survive and
prolonging the infestation. Its widespread use has allowed
resistance to develop(4,7).
Lindane also carries the risk of human toxicity.
Its primary deposition occurs in the brain's white matter(8).
Severe adverse reactions have been reported, including seizures,
which may occur as uncontrolled motor activity lasting for 48
hours or longer(7,8). The risk of this is enhanced when the
patient bathes before treatment, has dermatitis, or excessively
thin skin. Aplastic anemia and renal disorders also may occur(7).
Kwell was a major trade name for lindane for
many years, but it has been discontinued. However, generic
lindane products are still available. The pharmacist dispensing
the product should wear gloves while pouring it to prevent
unintended contact. Patients should be warned not to use more
than two ounces of lindane shampoo per application and to wear
gloves while using the shampoo. Since oils enhance absorption,
the patient must avoid application of any oil to the hair for
several days prior to lindane use. The lather must not touch any
areas other than the hair. Lindane should only be reapplied if
the physician has advised the patient to do so, and it must not
touch broken skin.
I was the pharmacist expert at a roundtable on
lice treatment in Boston several years ago. One of the attendees
was a structural pest eradication specialist. He reacted in
astonishment as I described the dangers of using lindane in
humans. When his turn came to speak, he stressed that lindane has
been prohibited in structural use for many years due to toxicity.
This should cause the pharmacist to question further any
application to humans.
Although many of the adverse reactions from
lindane were a result of misuse, it is prudent to take great care
with a product whose misuse can be deadly. In light of the
possibility of serious toxicity and the potential for resistant
lice, pharmacists should not recommend that physicians prescribe
lindane. Unfortunately, the patient may only be able to obtain
medication for head lice by relying on a third-party payer such
as the state. If reimbursement is limited to prescription items,
both patients and physicians turn to lindane, the only
prescription lice pesticide. Once again, the pharmacist may
choose to intervene, urging the patient to choose a lice
treatment based on safety to the patient rather than only on
Malathion. Malathion was once available
as the prescription product Ovide, but the odor of the
formulation was offensive to patients. For this reason, its sales
were inadequate to continue and the product is no longer
available. This organophosphate insecticide was a safer
prescription alternative to lindane, in that no systemic effects
with use were noted(7). The manufacturer once suggested that the
product might be relaunched, but this has not yet happened.
Synergized Pyrethrins. Pyrethrins are
chemical insecticides produced naturally by the Chrysanthemum
plant. However, lice can easily detoxify these chemicals through
oxidation unless a synergizing agent is added to enhance their
pesticidal activity. Piperonyl butoxide is a petroleum derivative
which accomplishes this. This combination was given Category I
status (safe and effective) by the FDA for pediculicidal use(9).
Shampoos containing synergized pyrethrins are applied to wet the
hair, while adding sufficient water to form a lather. The lather
is left in place for 10 minutes only. The patient then washes the
hair thoroughly with warm water and soap or nonmedicated shampoo.
Since the combination is not completely ovicidal, a second
treatment in 7-10 days is mandatory to kill any newly hatched
lice. While some synergized pyrethrin products claim to be
effective in only one dose, there is insufficient data to support
this claim, and a second dose is considered by the FDA to be
Patients allergic to either Chrysanthemums,
ragweed, kerosene or any petroleum derivative must not use
synergized pyrethrins. It must not be used near the eyes or
allowed to contact mucous membranes. The hands should be washed
thoroughly after application.
Several controversies have recently arisen in
regard to synergized pyrethrins. One is the increasing resistance.
Patients entering pharmacies are claiming that they have followed
the directions exactly, and are still infested with head lice. In
many cases, a cursory check confirms the presence of live lice.
Upon close questioning, it seems that the parent or caregiver has
indeed been conscientious in following the labeled directions,
leading the pharmacist to suspect resistance. Although it is
poorly documented at present, it seems that resistance to
pyrethrins is a growing problem.
Another controversy involves several false
advertising claims that were made by manufacturers. Among other
things, they claimed that synergized pyrethrin products (e.g.,
Pronto, RID, Clear Lice Killing Shampoo) are effective in one
dose, killing 100% of lice and eggs. One may visit the Federal
Trade Commission website to view the results of an agreement by
their manufacturers to settle charges of misleading consumers
with these false claims. The Director of the FTC stressed that
false and misleading claims such as these add insult to injury
for the patient already affected with head lice(10).
Permethrin. Permethrin (Nix Creme Rinse)
is a synthetic pyrethroid pesticide which was an Rx-to-OTC switch
in the early 1990s. The patient should shampoo and towel-dry the
hair and apply the product, leaving it in place for 10 minutes.
The product is then thoroughly rinsed from the hair.
Permethrin is only 70-95 percent ovicidal; the
manufacturer claims that less than one perdent of patients will
require a second treatment. The manufacturer also alleges that
residual effects protect against reinfestation for 14 days. This
is the basis for the advertising claim, "Only Nix--Only Once."
However, some patients will require a second treatment.
Pharmacists recommending this product should caution patients to
be continually vigilant after treatment to discover live lice
that indicate the need for the second treatment.
Patients with a Chrysanthemum allergy may also
be allergic to permethrin. Contact with the eyes or mucous
membranes should be avoided. Resistance to permethrin is emerging(11).
The growing resistance of head lice to synergized
pyrethrins and permethrin have caused many consumers to turn to
alternative methods of treating head lice. Some are ineffective
and dangerous, but diligent combing is rapidly emerging as the
treatment method of choice.
Hair Removal. The pharmacist should
advise against shaving the head of the individual infested with
head lice. While it is undeniably effective, the child may become
the focus of teasing among classmates.
Flammable Chemicals. Unfortunately,
reports of death and injury continue to accumulate when
individuals use flammable chemicals to treat head lice. Reports
of these accidents are usually confined to newspapers and news
media in the state where the accident occurred, which does not
allow one to gain a handle on the national scope of the problem.
Nevertheless, it is a growing phenomenon. In Oklahoma, a man
rubbed gasoline on his daughter's hair. It ignited, causing
second-degree burns to the father(12). Gasoline use on head lice
also caused an Oklahoma house fire which killed a baby. A 16-year-old
girl using gasoline experienced 2nd and 3rd degree burns over 90
percent of her body when a pilot light on a water heater ignited
the fumes(13). Another family used lantern oil, which ignited,
causing third-degree burns over 50 percent of the eight-year old
child's body and third-degree burns on the mother(14). Similar
fires have occurred with kerosene and other flammables. In all
probability, patients using old home remedies such as these have
not sought the advice of a pharmacist, perhaps due to
embarrassment. For this reason, the pharmacist must highlight the
dangers of these and similar home remedies whenever the
opportunity arises, such as any public health speaking engagement.
Dangerous Pesticides. Some people resort
to dangerous pesticides which are not meant to be used on humans.
For instance, some nonprescription veterinary flea preparations
may list lice on the label. People assume that they are safe for
human lice, using them indiscriminately on children and adults.
Their toxicity is unknown and their effectiveness for human lice
is questionable. They must be avoided.
Even worse, some patients resort to highly
concentrated pesticides. In an Oklahoma case, a six-year-old
child with head lice was treated with industrial strength
diazinon(15-17). Within 15 minutes, her respiration ceased and
she suffered full cardiac arrest. After almost three weeks in a
hospital, she was evaluated as having permanent brain damage.
Charges of child abuse were filed against the mother's boy friend
who treated the child, with bail being set at $100,000.
Eventually, the charges were dismissed, but the prosecutor
appealed that decision. Pharmacists must strongly advise against
any unapproved pesticide in humans.
Alternative Treatments. Several
companies have begun promoting wholly unproven head lice remedies.
They include tea tree oil, rue and other herbal ingredients.
These herbs suffer from a twofold problem: lack of information
about safety and absolutely unproven efficacy. Patients using
them suffer from a false sense of security that they are actually
treating the problem. This allows the head louse population to
increase unchecked, worsening the infestation and associated
symptoms. Pharmacists must advise against these natural herbal
interventions until sufficient data proving safety and efficacy
is submitted to the FDA.
Suffocating Treatments. Some patients
turn to friends and Internet sources, who have heard of
suffocating head lice by applying heavy oil-based products to the
head for varying lengths of time. As an example, patients are
advised to cover the hair with mayonnaise or olive oil and wrap
the head in plastic wrap, leaving it on overnight. There are
several problems with this approach. The efficacy of suffocating
agents is unproven, as there are no studies comparing them to
other remedies(18). The products must eventually be removed from
hair, and the heavy load of oil on the hair may require multiple
shampooing with harsh detergents. The net effect is irritation of
the scalp. Of course, the potential hazards of sleeping all night
with one's head covered in decomposing mayonnaise or rancid olive
oil are also vitally important. If one has open wounds on the
scalp, as many longstanding head lice sufferers do, bacterial
contamination of the mayonnaise or olive oil could cause a skin
infection. Pharmacists should advise against unproven therapies
such as oily suffocating agents.
Nit Cement Dissolving Agents. An old
home remedy is to use acidic products to dissolve the cement
holding the nit to the hair shaft. However, when patients have
used acidic products such as vinegar, they have caused facial and
ophthalmic burns(19). Use of vinegar should be discouraged.
Several commercial products which allege to
dissolve the nit cement have been marketed. Step 2 employs formic
acid, but its efficacy is unproven. Clear claims that its enzyme-based
approach dissolves the cement, but the manufacturer was cited by
the Federal Trade Commission for falsely claiming that the
efficacy was proven by laboratory and field studies(9).
Household and Environmental Sprays.
Several companies have marketed aerosol sprays which patients can
use to spray the environment. However, the use of these products
should be discouraged for several reasons. When a household
member has head lice, the major reservoir is the heads of the
victims. Few lice are found out in the surrounding environment,
unless they have been accidentally dislodged from the head during
acts such as scratching or combing. Another problem with
environmental sprays is that they foster the paranoia of affected
family members, who tend to overuse them, spraying all household
surfaces. Since these are pesticides, their safety upon
inhalation over a sustained period is unproven. One can only
imagine the toxicological effect of the pesticide on a sleeping
child lying face down on a heavily sprayed mattress and pillow
over a 10-hour sleep cycle. The safest and most effective
alternatives the pharmacist should recommend for environmental
lice removal is reassurance coupled with thorough vacuuming of
THOROUGH COMBING AS THE EMERGING
TREATMENT OF CHOICE
The various pesticides marketed for control of head
lice are toxic to the patient in varying degrees and lead to the
development of resistance. Other treatments are of unknown safety
and/or efficacy, and some are highly dangerous. For these reasons,
pharmacist recommendations should shift in the new millennium to
thorough combing with a highly effective comb such as the
LiceMeister®, which has been registered with the FDA
as a medical device(5). Its use was described above as a tool to
confirm an infestation. However, it also treats the infestation
by removing the nits. Resistance and toxicity are non issues with
this mechanical lice removal aid.
Students in their senior year realize that the real
world is uncomfortably close. They appreciate learning about
nonprescription products from a faculty member who is a
registered pharmacist and who also continually works in a retail
pharmacy. This ongoing practice paid off handsomely in the area
of head lice treatment by allowing me to gain an early
appreciation for the emerging problem of resistance, as evidenced
by the large numbers of people with whom I consulted and for whom
traditional nonprescription products were ineffective. It also
allowed me to recommend an improved way to eradicate head lice,
and to monitor patients who purchased it. Describing these actual
work situations to students enriches the academic experience and
helps students bring the most effective treatments to their
patients when they enter their own practice settings.
Am. J. Pharm. Educ., 63, summer
(1) Janniger, C.K. and Kuflik A.S, "Pediculosis
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