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| Atopic dermatitis (AD)
is a chronic and a prevalent form of eczema characterized
by itchy, red, inflamed, scaling, cracking, weeping,
and crusting skin. Although atopic dermatitis commonly
affects infants and young children, it can continue
into adulthood or show up later in life for the
first time. It is estimated that 10% of infants
and young children develop symptoms of AD. Approximately
60% of these infants continue to have symptoms of
AD into adulthood which means more than 15 million
people in the United States have symptoms of AD.1
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Although the specific cause of AD is not known, the
disease seems to result from a combination of genetic
(hereditary) and environmental factors. Research suggests
that it is related to other disorders, such as hay fever
and asthma which many people with AD develop. AD is
not contagious, and stress can make it worse. Because
the skin is dry and itchy, AD sufferers often scratch
which can cause infection. Consequently, the skin of
AD sufferers is susceptible to infection because the
stratum corneum, a barrier that prevents skin from drying
out and from the damage of irritants and infections,
is damaged.1
Conventional treatment for AD varies depending on the
patient’s age, symptoms, and general health. The
main goals of treatment are to heal the skin and keep
it healthy, prevent flare ups, and treat symptoms when
they occur. Proper skin care and lifestyle changes are
effective for some AD sufferers. Patients are advised
to develop skin care routines (e.g. use a cream or ointment
on the skin after bathing), identify factors that exacerbate
AD, and avoid circumstances that trigger the skin’s
immune system and the itch-scratch cycle.1
When itching and rash fail to be controlled, medication
is added to the patient’s daily skin care routine.
Medication is also required if infection is present.
The most frequently used conventional medications are
corticosteroid creams and ointments. Antibiotics for
skin infection may be applied topically or taken orally,
and antihistamines are commonly taken to reduce itching
and allergy symptoms. Other treatments include phototherapy
(treatment with ultraviolet light), photochemotherapy
(combination of ultraviolet light therapy and psoralen),
and immunosuppressive drugs (e.g. cyclosporine). Severe
cases of AD that fail to respond to common treatments
are prescribed systemic corticosteroids (e.g. prednisone)
in which the corticosteroids are given orally or injected
into muscle.1
The drawback to most of the conventional treatments
for AD are the side effects. For example, the side effects
of corticosteroids include skin damage, thinned or weakened
bones, high blood pressure, cataracts, high blood sugar,
and infections. Similarly, cyclosporine’s (immunosuppressive
drug) side effects include high blood pressure, nausea,
kidney problems, vomiting, headaches, tingling or numbness,
and an increased risk of cancer and infections. Similarly,
long-term treatment with ultraviolet light can cause
premature skin aging and skin cancer.1
Due to the side effects of the conventional AD medications,
scientists are actively searching for alternative treatments.
Uehara et al.2 tested the
effectiveness of oolong tea in 118 patients with recalcitrant
AD. Patients were instructed to maintain their normal
dermatological treatment programs, and they drank oolong
tea daily after 3 regular meals. (Oolong tea is partially
oxidized. Black tea is manufactured to ensure a high
degree of enzymatically catalyzed aerobic oxidation
of tea polyphenols (e.g. catechins). Green tea is not
oxidized in order to preserve the leaf polyphenols.3)
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