OTC Options: Controlling Dandruff
by Audrey T. Hingley

     If you're troubled by dandruff, that snowy, dust-like stuff
that falls from scalp to shoulders, you're not alone: Nearly
everyone has dandruff to some degree.
     Dandruff is treatable with over-the-counter (OTC) products and
causes no general health problems or permanent damage. But care
must be taken not to confuse simple dandruff with other conditions
that also cause flaking of the scalp, such as seborrheic dermatitis
or psoriasis.
     Dandruff occurs when the scalp sheds dead epidermal (skin)
cells in large clumps. Dandruff scales appear dry, white or
grayish, appearing as small, unsightly patches, especially on top
of the head.
     Scalp cells replenish themselves in a pattern similar to that
of hair, but more rapidly: The skin of the head renews itself about
once a month. Dead scalp cells are constantly being pushed from the
deepest layer of the epidermis to the skin's surface, where they
gradually die. Usually the scalp sheds them in a nearly invisible
way. But for reasons that are still unclear, cell turnover
sometimes becomes unusually rapid, and dead cells are shed as the
visible flakes called dandruff.
     In 1990, FDA banned 27 ingredients in dandruff shampoos
because they were not proven safe and effective. Today dandruff can
be treated with OTC drug products containing five ingredients FDA
has verified as safe and effective: salicylic acid, pyrithione
zinc, sulfur, selenium sulfide, and coal tar. FDA allows drug
products to be sold without a prescription if they are safe for
consumer use without a doctor's supervision and provide adequate
detailed information for use on their labels.
     Approved OTC ingredients for dandruff treatment are available
in shampoos, rinses, or in products that users apply and leave on
the scalp. Each works in different ways to control dandruff
symptoms like scaling or itching.
     OTC drug products are available in an estimated 750,000
outlets nationwide, including pharmacies and supermarkets,
according to the Nonprescription Drug Manufacturers Association
(NDMA). NDMA also reports that dandruff is among the top 10
problems consumers are most likely to treat with OTC drug products:
59 percent of the time dandruff sufferers use OTC drug products.
     Coal-tar preparations and salicylic acid are approved for
treating dandruff, seborrheic dermatitis, and psoriasis; pyrithione
zinc and selenium sulfide for dandruff and seborrheic dermatitis;
sulfur for dandruff; and salicylic acid and sulfur in combination
for dandruff treatment. On Jan. 28, 1994, FDA published a final
rule amending the monograph published in the Dec. 4, 1991, Federal
Register allowing micronized selenium sulfide in a concentration of
0.6 percent to be included as an active ingredient to control
dandruff.
     According to Ida I. Yoder, a chemist in FDA's Office of OTC
Drug Evaluation and a member of its drug policy staff, micronized
selenium sulfide is a very finely ground form of selenium sulfide,
with a particle size of approximately 5 micrometers. Because the
selenium sulfide is more finely ground, it can be  used at lower
concentration levels.
     "A drug is intended for use in the diagnosis, cure,
mitigation, treatment, or prevention of disease, or intended to
affect the structure or function of the body," says Yoder. Shampoos
classified as cosmetics cannot make such medical claims. They are
marketed for cleansing, beautifying, or promoting attractiveness.
     If a product only claims to wash off dandruff flakes, it could
be considered a cosmetic, Yoder says. But if it claims to prevent
or treat the condition, it's considered a drug.

What Makes the Flake?
     Although most people assume dandruff comes from a dry scalp,
the opposite is true: People with oily scalps tend to suffer most
from dandruff.
     "This may be due to an oily scalp supporting the growth of
yeast in the scalp, which is thought to be instrumental in the
development of scaling and scalp irritation," says Joseph P. Bark,
M.D., chairman of dermatology at St. Joseph's Hospital in
Lexington, Ky. "A large preponderance of males have dandruff, which
may suggest some role of androgen hormones in dandruff."
     Children under 10 rarely have dandruff, but it is common in
adolescents. While some experts say it tends to decrease in middle
and old age, Bark disputes this.
     "It really is a postpubescent disease, but I don't believe it
diminishes in old age. We see a lot of dandruff and seborrheic
dermatitis in stroke patients and in older people," he explains.
     Bark says that dandruff has its bright side: If the scalp
doesn't shed its dead skin cells, the human scalp would be
tremendously thick.
     "But when the cell turnover goes too far and increases, then
you get not only visible excess scaling, but redness and itching,"
he says. "Redness and itching is actually seborrheic dermatitis,
and it frequently occurs around the folds of the nose and the
eyebrow areas, not just the scalp."
     Although seborrheic dermatitis mimics dandruff with its flaky
scales, the inflammation and itching that accompanies it sets it
apart from simple dandruff. OTC preparations are available to help
mild cases, but seborrheic dermatitis often is best treated by
prescription medications.
     "All the evidence points strongly to this yeast, known as
Pityrosporum ovale, as a causation of seborrheic dermatitis, in
that when you treat it with anti-fungal shampoos [such as Nizoral
(ketaconazole) a prescription shampoo], you destroy the organism
and the condition stops," Bark says.
     What do you do if you have dandruff but suspect your problem
may be a more severe disorder like seborrheic dermatitis?
     "If you have mild scaling, you can usually take care of it
with an OTC dandruff shampoo containing salicylic acid," Bark
advises. "Use it for several weeks, and if you don't see a clear-
cut improvement in the scaling, consult a dermatologist. A
dermatologist can diagnose whether you have a fungus infection of
the scalp, seborrheic dermatitis, or some other disorder."
     A form of seborrheic dermatitis that sometimes alarms new
parents is known as "cradle cap." The scaly scalp inflammation is 
common in newborn babies, although it can occur anytime in infancy.
Rubbing warm olive or mineral oil into the baby's scalp and leaving
it on overnight can loosen and soften scales, which can be washed
off the next day with a mild shampoo. It usually clears up quickly
and does not recur.

Psoriasis
     Psoriasis is an inflammatory skin disease in which skin cells
replicate at a rapid rate. Although the symptoms of psoriasis--
silvery scales covering reddened areas of the scalp--seem similar
to dandruff, psoriasis is very different. New skin cells are
produced about 10 times faster than normal, but the rate at which
old cells are shed is unchanged. Live cells then accumulate and
form the thick patches covered with flaking skin.
     The scales are heaped-up, and the disorder may involve other
areas of the body besides the scalp, most commonly the knees,
elbows, back, or buttocks. It can also affect legs, arms, and just
about any other part of the body. Psoriasis can be chronic or it
may have periods of flare-ups and remission periods.
     Psoriasis is annoying mainly because of its tendency to return
again and again, and because of its unsightly, blotchy appearance.
It is more common in whites than in blacks and Asians.
     If you think you may have psoriasis, consult a doctor about
treatment.

Coal Tar
     Coal tar, one ingredient in OTC dandruff products, is a
byproduct of treated bituminous coal. In constant exposure to
concentrated solutions in industrial settings over long periods (20
to 25 years), coal tar has been associated with skin cancer. But
coal-tar products are considered safe for topical use in shampoos
because contact with the scalp is only for a short duration.
     For body seborrheic dermatitis and psoriasis, however,
products containing coal tar remain on the skin for longer periods.
There are no well-defined, long-term studies that demonstrate how
long coal-tar products can be used safely. FDA has noted that
prolonged use of such products may not be completely risk free due
to possible cancer-causing effects.
     Coal tar also produces photosensitivity reactions (reactions
that occur with exposure to sunlight). Residual amounts of coal tar
may remain on the scalp, hair, or surrounding areas after using. So
if you're going out in the sun after shampooing with these
products, you may want to take extra precautions.
     FDA requires OTC dandruff products that contain coal tar to
state on their labels, "Do not use for prolonged periods without
consulting a doctor. Use caution in exposing skin to sunlight after
applying this product. It may increase your tendency to sunburn for
up to 24 hours after application."
     Coal-tar shampoos also tend to give an orange tinge to light-
colored hair.
     Dave Bostwick, a reviewer in FDA's division of anti-infective
drugs, Office of Drug Evaluation II, says one alternative to using
OTC products to control dandruff is  mechanical.
     "Washing your hair more often means you remove dandruff flakes
that otherwise would remain on the head," he says.
     Other than washing your hair more frequently, there is really
no way to control dandruff without treatment. So if you find you're
flakier than you'd like to be, OTC drug products may solve your
problem.

Audrey T. Hingley is a writer in Mechanicsville, Va.