Skin: Drug-Induced Pigmentation
Women with brown skin, particularly those of African
and Latino descent, have a high incidence of hypertension, diabetes
and heart disease and consequently take medications for those medical
problems. These, as well as other commonly used medications, can cause
various types of allergic reactions that frequently lead to hyperpigmentation
(dark patches). There are four primary types of medication reactions
that can lead to often troubling and disfiguring hyperpigmentation: fixed drug eruptions, photosensitivity reactions, drug-induced
hyperpigmentation and drug eruptions with secondary post-inflammatory
hyperpigmentation.
A fixed drug eruption is a round, dark
patch or eruption that results from a reaction to a drug (usually a
prescription medication). This type of reaction leaves a grey-blue,
round patch on the skin. The round patch is usually fixed to one spot
will appear in this same location within 24 hours of each dose taken.
There are several medications that can cause a fixed drug eruption,
including:
- Non-steroidal anti-inflammatory drugs (NSAID): sulindac,
naproxyn
- Anti-yeast medications: nystatin
- Pain relievers: fiorinal (migraine headaches), salicylates (aspirin)
- Antibiotics: tetracycline, minocycline, sulfonamides, metronidazole
- Laxatives: phenolphthalein
- Oral contraceptives
- Sulfonamides: bactrim
Photosensitivity reactions occur as
a result of a direct interaction between the sun and a medication that
you are taking. In the case of a photosensitive reaction, brown or blue-grey
patches will develop in areas of the skin exposed to the sun, including
the face, tops of the ears, V of the neck, and outside of the arms.
Areas under the chin, immediately behind the ears, and other areas shielded
from direct sunlight, are typically spared and your normal skin color
will remain. With most photosensitivity reactions, the pigmentation
develops slowly without a skin rash and intensifies after exposure to
the sun. In other cases, a red sunburn-like reaction, a blistering reaction,
or a bump-like reaction may develop prior to the onset of the hyperpigmentation.
Some of the medications that can cause a photosensitivity reaction are
listed below:
- Diuretic or water pill: thiazide
- Nonsteroidal anti-inflammatory agent (NSAID)
- Antibiotics: tetracyclines, sulfonamides
- Antihypertensives and heart medications: procainamide, hydralazine sngiotensin converting enzyme inhibitors
- Hypoglycemic drugs for diabetes: sulfonylureas
Drug-induced hyperpigmentation is hyperpigmentation
(dark patches) caused by a reaction between a component of the medication
and your skin. The pigmentation often occurs on the face, especially
around the mouth. Other parts of the body may be affected as well. The
exact cause of the pigmentation is unknown. Several examples are listed
below:
- Antibiotics: minocycline
- Anti-malarial and lupus medications: chloroquine and hydroxychloroquine.
As mentioned earlier, medications for hypertension,
diabetes, and heart disease, all too common medical problems for African
American and Latina women, frequently cause red or skin colored, itchy
rashes. These allergic hypersensitivity rashes can occur anywhere on
our bodies and usually require 7 to 10 days to resolve after the medication
has been stopped. The reaction then fades away leaving dark marks in
the areas where the rash was, termed post-inflammatory hyperpigmentation. There are a variety of medications
that can cause allergic hypersensitivity reactions and subsequently post-inflammatory hyperpigmentation. Some of these
medications include:
- Allopurinol (gout)
- Antibiotics: penicillin, sulfonamides
- Antiepileptics: phenytoin, phenobarbitol
- Antihypertensives: captopril, thiazide diuretics
- Contrast dye: iodine
- Gold salts: arthritis
- Hypoglycemic drugs: diabetes
- Phenothiazines: mental disorders
- Quinine: leg cramps
In the case of fixed drug eruptions, and photosensitivity
reactions, the pigmentation is often in the lower layers of the skin
(dermis). This makes treatment difficult if not impossible since currently
available treatments are unable to penetrate the lower layers of the
skin. This makes early detection and immediate discontinuation of the
medication extremely important. If you notice that your skin is getting
darker, especially after sun exposure, call your medical doctor immediately
and ask if the medication can be discontinued and a substitute provided.
Also, when you are taking any medication, the use of SPF 15 or higher
sunscreen becomes even more important. Fortunately, an allergic hypersensitivity
reaction to a medication with secondary post-inflammatory hyperpigmentation
usually responds to treatments as discussed in the post-inflammatory
hyperpigmentation section. It is nonetheless important to discontinue
the medication at the first onset of a rash.
