Drug-Induced Pigmentation | Skin, Urine

Introduction
Drug-induced pigmentation affects both the skin and urine. Many pigmentation effects are predictable. Some are not so predictable and require a few minutes of your study time. Here, we’ve put together the key details you need to know.
Drug-induced pigmentation, or coloring, is a common side effect. It impacts many of the most commonly used medicines from tetracyclines and antimalarials, to NSAIDs and iron.
Below, we’ve put together a comprehensive list of 20 drug-induced pigmentation effects that you need to know. Whether you are taking a clinical pharmacy exam or are practicing NAPLEX questions for your upcoming license test, you must know all these adverse effects. These side effects are, after all, routinely examined.
You may not have heard of some of the tabled syndromes.
‘Purple glove syndrome’ (PGS) is one such example. Phenytoin is the causative agent; a syndrome characterised by swollen, purple discolored extremities. The pathogenesis of PGS is currently poorly understood.
‘Red man syndrome’ is another example, this time caused by vancomycin. As the name suggests, patients experience a red erythematous upper body rash, often shortly after drug administration.
Of course, a ‘rash’ itself is not a consequence of pigmentation. However, given the ubiquity of the name and its association with vancomycin, we have included it here as an ancillary revision tool.
Drug-Induced Pigmentation
Take a few minutes, then, to review the table below.
After you commit all twenty drug-induced pigmentation effects to memory, you are well placed to perform maximally on your next pharmacy test.
Drug | Side Effect |
---|---|
Ethambutol | Red-green color blindness |
Rifampin | Red-orange urine, sweat and tear |
Nitrofurantoin | Brown urine |
Vancomycin | Red man syndrome |
Phenytoin | Purple glove syndrome Dark brown skin patches |
Clofazimine | Brown-pink skin pigmentation |
Phenazopyridine | Orange urine |
Cimetidine | Blue urine |
Amiodarone | Blue-gray skin discoloration |
Tetracyclines | Discoloration / hypoplasia of tooth enamel |
Minocycline | Blue-gray skin pigmentation |
Iron | Black stools |
Bismuthsubgallate | Black tongue discoloration |
Prostaglandin analogs – Bimatoprost – Latanoprost | Permanent iris discoloration |
Heavy metal salts | Silver discoloration, gold discoloration etc. |
Chlorpromazine | Bluish-gray skin pigmentation |
Chloroquine Hydroxychloroquine | Blue-gray skin pigmentation |
NSAIDs | Fixed drug eruptions Erythematous lesions that leave local brown pigmentation. May occur on face, extremities or genitalia. |
Cytotoxic drugs Busulfan Cyclophosphamide Bleomycin | Hyperpigmentation of skin Diffuse pigmentation of nails |
Final Thoughts
As part of your clinical pharmacy license exam, candidates are expected to have a rounded understanding of adverse effects. One of the great ways to commit side effects to memory is to classify those effects as much as possible.
Here, we’ve done exactly that. NAPLEX questions often ask about these types of prominent side effect. They are both memorable and interesting and worth a few minutes of your study time.
Review this table tomorrow and in 3 days and in 7 days from now. Commit these adverse effects to memory. That way, there will be no unpleasant surprises on the day of your next pharmacology exam.
NAPLEX Study Guide is the leading provider of premium pharmacy-like exam questions. Our NAPLEX questions cover the clinical detail you need to know. Check back to our pharmacy blog soon for even on drug-induced pigmentation and other great study tools.