US
Pharm. 2006;4:34-42.
Acne vulgaris is the most
common skin disease, affecting about 17 million Americans in all age-groups
and ethnic backgrounds.1 Although the condition can occur at any
age, it affects primarily teenagers and young adults between the ages of 12
and 24; nearly 85% of people in this age-group get acne. While most cases
resolve by age 30, for some people, the condition persists into middle age.
1
Characterized by
noninflammatory follicular papules and, in its more severe forms, by
inflammatory papules, pustules, and nodules, acne occurs when the pores of the
skin become clogged with oil, dead skin cells, and bacteria. The condition
typically affects the areas of skin with the densest population of sebaceous
follicles, including the face, upper chest, and back. Although not curable,
early treatment and regular preventive skin care can minimize mild to moderate
cases, and prescription medications can effectively treat acne in even its
most severe forms.
The Skin
The skin is the
largest organ of the body, forming a protective barrier against harmful agents
in the environment. Functions of the skin include helping to maintain proper
body temperature through the evaporation of sweat and the insulation of fat in
the subcutaneous tissue, gathering sensory information from the environment,
and facilitating calcium homeostasis through vitamin D synthesis.2
Melanin, a pigment produced in the skin, protects cell nuclear structures from
damage by ultraviolet radiation.2
The skin comprises three
layers: the epidermis, the dermis, and subcutaneous tissue (figure 1). The
epidermis consists of multiple layers known as the stratified epithelium
and renews itself continuously by cell division in its deepest layer, the
basal layer. Cells produced by cell division undergo a process called
keratinization, which deposits the fibrous protein keratin and causes the
cells on the surface of the skin to form a horny layer called the stratum
corneum, the outermost layer of the epidermis. The stratum corneum
consists of flattened keratinized cells devoid of nucleic and cytoplasmic
organelles. Adjacent cells overlap at their margins, causing cells to lock
together with intercellular lipid and to form a very effective barrier that
helps prevent the rapid loss of water. While the thickness of the stratum
corneum varies from region to region of the body depending upon the amount of
friction from contact with other surfaces, the thickest areas are found over
the palms of the hands and the soles of the feet.2
The dermis, located below the
epidermis, contains small blood vessels that provide nutrition to skin cells
and nerves involved in sensory transmission and to specialized structures,
such as hair follicles, sebaceous glands, and sweat glands.2
Sebaceous glands are attached to the follicles and are found on all areas of
the skin except the palms of the hands and soles and dorsa of the feet. Most
sebaceous glands open into hair follicles, known as the pilosebaceous units
, while others open directly to the skin surface on the eyelids, prepuce,
female
genitalia, and areola.2
The subcutaneous layer is
below the dermis and contains larger nerves and blood vessels that regulate
body temperature by conducting heat from the internal organs of the body to
the surface of the skin. Maximal vasodilatation of all skin blood vessels can
increase blood flow to the skin up to seven times the normal volume. The
skin's circulatory system serves as a large blood reservoir,
representing 5% to 10% of the body's total blood volume. Under
circumstances of circulatory stress (e.g., hemorrhage), vasoconstriction
forces this blood into the general circulation. This layer also contains
subcutaneous fat that facilitates thermoregulation by insulating tissues
beneath the skin.2
Pathophysiology of Acne
Acne is described
as a disease of the pilosebaceous units (figure 2), which are most numerous on
the face, upper back, and chest. Sebaceous glands produce an oily substance
called sebum that normally empties onto the surface of the skin through
the opening of a follicle known as a pore. Keratin-producing cells
called keratinocytes line the follicle.1 When acne occurs,
the hair, sebum, and keratinocytes that line the pilosebaceous unit form a
plug that does not allow sebum to flow to the surface. These plugs allow
Propionibacterium acnes, bacteria that normally live on the surface of the
skin, to grow in the plugged follicles. The presence of P. acnes
attracts white bloods cells and causes inflammation, characterized by
swelling, redness, heat, and pain. Inflammation leads to a variety of lesions
known as pimples (figure 3).1
An enlarged, plugged follicle
forms the basic acne lesion, known as a comedo. If the plugged follicle or
comedo stays beneath the skin, it produces a white bump called a whitehead
, or a closed comedo. A comedo that reaches the surface of the skin is
called an open comedo or a blackhead, because the sebum turns
black when exposed to air.
Other acne lesions include
papules, pustules, macules, nodules, and cysts.1 A papule is formed
by a cellular reaction to the process of comedo formation. A papule is a small
(5 mm or less), solid lesion slightly elevated above the surface of the skin.
Papules may be so small that they are almost invisible, but may give the skin
a "sandpaper" feel.3 A dome-shaped, fragile lesion
containing pus is called a pustule. Pus is a combination of white blood
cells, dead skin cells, and bacteria. Pustules can heal without leaving scars
or can progress to cystic forms. A macule is a temporary flat, red spot
left by a healed acne lesion. Macules can persist for days or weeks and
contribute to the inflamed appearance of acne. A nodule is a solid,
dome-shaped, or irregularly shaped lesion that can be painful. Unlike
pustules, nodules are characterized by inflammation, extend into the deeper
layers of the skin, and may cause tissue destruction resulting in scarring.
3 Cysts are sac-like lesions containing liquid or semiliquid
material of dead cells, white blood cells, and bacteria. Cysts are larger than
pustules, extend into the deeper layers of the skin, and can be very painful
and often cause scarring. Cysts are a severe form of acne that is resistant to
most treatment.3
Factors Contributing to
Acne
While the exact
cause of acne is unknown, contributing factors have been identified.
Fluctuations in hormones are known to worsen acne. Increased levels of
androgens during puberty in males and females cause sebaceous glands to
enlarge and produce more sebum. In females, hormonal changes before
menstruation or during pregnancy can worsen the condition, and initiating or
discontinuing the use of birth control pills can also contribute.
Additionally, a family history of acne increases the likelihood of acne.4
A number of prescription
medications, including anticonvulsants, anti-inflammatory corticosteroids, and
immunosuppressants are known to cause or worsen acne (table 1).
Pressure on the skin from athletic equipment, backpacks, or tight clothing can
make acne worse. Greasy cosmetics or grease from the work environment (e.g.,
from cooking or working on machinery) can also aggravate the condition, and
environmental irritants, such as pollution and high humidity, are associated
with acne flare-ups. Although not considered a cause of acne, stress can
exacerbate acne. In addition, hard scrubbing irritates the skin and triggers
inflammation, while squeezing or picking blemishes pushes bacteria from the
surface of the skin into the pilosebaceous units and contributes to comedo
formation.1
There are many misconceptions
about causes of acne. Although chocolate and greasy foods are often blamed for
causing acne, there is little evidence that foods have much effect on the
condition. Another common misconception is that dirty skin causes acne. Dirt
does not contribute to lesion formation.1
Acne Treatment
Over-the-counter
(OTC) and prescription medications are used both topically and orally to treat
acne. Treatment goals include healing existing lesions, preventing scarring
and the formation of new lesions, and minimizing psychological stress and
embarrassment. Different factors that contribute to lesion formation are
targeted to reduce sebum production, inflammation, and abnormal clumping of
cells in follicles involved in plug formation and to control bacterial growth.
5
OTC
medications:
Topical OTC products are often used for mild to moderate acne. Benzoyl
peroxide, which kills P. acnes and may reduce sebum production, has
been the mainstay of acne prevention for years. Benzoyl peroxide is available
in strengths ranging from 2.5% to 10% and in a variety of preparations,
including creams, gels, solutions, lotions, pads, and cleansers. Before
applying benzoyl peroxide, patients should wash the affected area with mild,
nonmedicated soap or skin cleanser and allow the skin to dry completely to
reduce skin irritation. The skin should not be rubbed, but rather patted dry
with a soft towel. Patients should apply enough medication to completely cover
the affected areas and rub in gently while avoiding sensitive areas, such as
those around the eyes, lips, in and around the nose, and areas of the neck.
When treatment with benzoyl
peroxide is initiated, skin may feel irritated and acne may worsen. If acne
does not improve within four to six weeks or if skin irritation is severe,
patients should discontinue benzoyl peroxide products and consult a physician.
5 Pharmacists should instruct patients to not apply benzoyl peroxide to
open wounds or windburned or sunburned skin and to not use other irritating
products (e.g., peeling agents, hair removal products, agents containing large
amounts of alcohol, abrasives, or drying agents) unless directed by a
physician.5
Other OTC topical products
used to treat acne contain resorcinol, salicylic acid, and/or sulfur. These
products help break down plugs in lesions and decrease shedding of cells
lining the hair follicles.1
Prescription
medications:
Moderate to severe acne may be treated with prescription oral and topical
medications alone or in combination. Prescription topical medications include
anti biotics, benzoyl peroxide, sodium sulfacetamide/sulfur combinations,
azelaic acid, and vitamin A derivatives (retinoids). Retinoids work by
unplugging existing comedones and decreasing the formation of new comedones
and include such agents as tretinoin, adapalene (Differin/Galderma
Laboratories), and tazarotene (Tazorac/Allergan).1
Prescription topical
medications may cause minor side effects, such as stinging, burning, redness,
peeling, scaling, or discoloration of the skin. Patients should notify their
physician if side effects are severe or do not disappear. Prescription topical
medications may not have an immediate effect, and it may take four to eight
weeks before signs of improvement are visible. In addition, a patient's
condition may worsen before it improves.
Oral and topical antibiotics
control bacterial growth and reduce inflammation and are often used in
combination. Commonly used oral antibiotics include tetracycline, minocycline,
and doxycycline; oral antibiotics less commonly used are clindamycin,
erythromycin, and sulfonamides. Side effects from oral antibiotics can include
upset stomach, dizziness, changes in skin color, and increased tendency to
sunburn. Since tetracyclines can affect tooth and bone formation in fetuses
and young children, they are not used in pregnant women or in patients younger
than 14 years.1
Severe cystic acne should be
treated by a dermatologist, as it is often resistant to the treatments
mentioned above. Cystic acne usually requires treatment with isotretinoin
(Accutane/Roche), a retinoid that reduces the size of sebum-producing glands,
to decrease oil production. Isotretinoin is taken orally once or twice daily
for 15 to 20 weeks. Acne completely or almost completely disappears after 15
to 20 weeks of treatment with isotretinoin. If acne recurs, it can be treated
with isotretinoin again or with other medications.
Since isotretinoin causes
birth defects in developing fetuses, it is very important that women of
childbearing age are not pregnant or do not become pregnant during treatment.
Women must use two forms of birth control at the same time for a minimum of
one month before treatment, during treatment, and for at least one month after
treatment. In addition, pharmacists must register to prescribe and dispense
iso tretinoin to ensure that it is not given during pregnancy. Both male and
female patients who are prescribed isotretinoin must be registered to fill
their prescriptions. Prescriptions must contain an authorization number, which
is acquired by the physician when registering a patient; the number is then
reported to the manufacturer by the pharmacist when the medication is
dispensed.
Other possible side effects
of isotretinoin include dry eyes, lips, nose, and skin, itching, nosebleeds,
muscle aches, sensitivity to sunlight, poor night vision, increased blood
triglycerides and cholesterol, and changes in liver function. Side effects
usually resolve after treatment is completed.1
In some women, increased
levels of androgens cause acne. This type of acne can be treated with oral
contraceptives, low-dose corticosteroids, or spironolactone. Oral
contraceptives and corticosteroids reduce androgen production by the ovaries
and adrenal glands, respectively. Spironolactone has antiadrenergic
properties. Spironolactone is a 17-lactone steroid that binds to androgen
steroid receptors, thus blocking the effects of these androgens. Side effects
of antiadrenergic medications include breast tenderness, irregular
menstruation, headaches, and fatigue.1
Psychological Impact of
Acne
Although acne is a minor medical
condition that rarely has significant physical health consequences, the
condition can have serious negative effects on psychiatric health,
psychological well-being, and quality of life. Factors that contribute to the
condition's psychological impact include its prevalence in adolescents,
distribution of visible lesions on the face, back, chest, and upper arms,
misconceptions regarding its causes, and social emphasis on appearance.
Adolescence is a period of physical, emotional, and social development, and
adolescents with acne may experience psychosocial complications. In addition,
almost 30% of the American population believes that poor skin hygiene is a
cause of acne.6 Such beliefs can cause patients to feel
embarrassment, guilt, and shame. It is not surprising that when patients with
acne were asked what bothers them the most about the condition, the most
common response was appearance.7
Acne has been identified as
a contributing factor of psychiatric disorders, including clinical depression,
social phobias, and anxiety disorders.8,9 Acne can also negatively
affect psychosocial functioning. Studies have identified significant
impairment of self-esteem, self-image, well-being, and satisfaction with
appearance in patients with acne, which inhibit social interaction.8-11
In addition, the condition has been shown to significantly affect quality of
life.7 One study showed that 74% of patients with acne waited more
than one year before seeking medical attention.6 This is an
important concern because delaying treatment increases the likelihood of
permanent scarring and allows time for patients to develop negative feelings
about themselves. A study examining 111 patients before and after a variety of
acne treatment modalities showed substantial improvements in quality of life
and self- esteem with acne treatment.12
Such potentially serious
psychosocial consequences must be considered when treating acne. Pharmacists
can have a vital role in the effective treatment of acne, which can yield
tremendous positive results in the self-esteem, self-image, and quality of
life of patients. Patients should be encouraged to seek early treatment to
minimize the chance of permanent physical scarring and negative psychological
effects (table 2). Pharmacists should strive to be accessible, informed, and
positive when counseling patients with acne.
Conclusion
Acne is a common
dermatological problem that affects about 17 million Americans. The condition
affects both men and women primarily during adolescence and can have
significant negative psychological and psychosocial effects. Mild to moderate
cases of acne can be minimized with early treatment and regular preventive
skin care; in its most severe forms, acne can be effectively treated with
prescription medications. Pharmacists can have a vital role in the effective
treatment of acne, which can have a tremendous positive impact on a patient's
self-esteem, self-image, and quality of life. To treat the entire person and
not just the skin condition, the nondermatological effects of acne must be
addressed.
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HL, van der Schaar WW, van den Hurk CM. The psychological impact of severe
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