Drug-Induced Pigmentation | Skin, Urine

drug induced pigmentation


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.

DrugSide Effect
EthambutolRed-green color blindness
RifampinRed-orange urine, sweat and tear
NitrofurantoinBrown urine
VancomycinRed man syndrome
PhenytoinPurple glove syndrome
Dark brown skin patches
ClofazimineBrown-pink skin pigmentation
PhenazopyridineOrange urine
CimetidineBlue urine
AmiodaroneBlue-gray skin discoloration
TetracyclinesDiscoloration / hypoplasia of tooth enamel
MinocyclineBlue-gray skin pigmentation
IronBlack stools


Black tongue discoloration
Prostaglandin analogs

– Bimatoprost

– Latanoprost

Permanent iris discoloration
Heavy metal saltsSilver discoloration, gold discoloration etc.
ChlorpromazineBluish-gray skin pigmentation


Blue-gray skin pigmentation
NSAIDsFixed drug eruptions

Erythematous lesions that leave local

brown pigmentation. May occur on face,

extremities or genitalia.

Cytotoxic drugs




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.


Join Our
Mailing List For Even More Facts!

    Don't stop
    learning now!

    Follow us
    on social media:

    vancomycin pharmacology
    NAPLEX Study Guide Pharmacology

    Vancomycin Pharmacology Guide!

    October 30th, 2023 By admin

    Read More
    carbamazepine pharmacology
    NAPLEX Study Guide Pharmacology

    Carbamazepine Pharmacology!

    November 26th, 2023 By admin

    Read More
    facts about tetracyclines
    NAPLEX Study Guide Pharmacology

    Top 10 Facts about Tetracyclines

    September 28th, 2023 By admin

    Read More

    2023 © naplexstudyguide.com. ALL RIGHTS RESERVED.