TOP 5 unusual drug side effects

1. Fingerprint loss
A few years back, a 62-year-old male was held by US immigration officers at the airport customs for four hours before they allowed him to enter the country since they could not detect his fingerprints. Turns out he was taking a chemotherapy drug called capecitabine. Fingerprints reportedly disappear as the skin peels in reaction to the drug.

It’s temporary, but it can compromise identification in the meantime. Patients going abroad should carry a doctor’s note indicating that they are taking this drug to avoid inconvenience, since some countries require fingerprint identification upon entry and departure.

2. Eyelash growth
Bimatoprost is a synthetic prostamide analog and a potent ocular hypotensive agent which regulates the flow of fluid within the eye to maintain a normal pressure and treat certain types of glaucoma. Since prostamides can also make eyelashes grow longer and thicker, their use as cosmetic eyelash enhancers is becoming more popular. However, pharmacists should advise that all prescription-only medicines should only be used under medical supervision especially those used outside their licensed indications.

3. Black tongue
Used for indigestion, nausea, or diarrhea, the pink medication can make your tongue and stool turn charcoal black. This temporary and harmless effect occurs when bismuth subsalicylate (the active ingredient) interacts with hydrogen sulfide in mouth and colon. Depending on the time it takes for food to move through the colon, the stool can remain dark for several days after treatment discontinuation.

4. Hair color changes
Hair color modifications comprise lightening/greying, darkening, or even a complete hair color change, including the scalp and/or all body hair.

Even if hair color change is not a life-threatening side effect, it is of deep concern for patient’s quality of life and adherence to treatment.
Sporadic cases of hair whitening/discoloration or darkening have been described with vitamin A derivatives, such as acitretin and etretinate. Isolated cases of hair darkening with indinavir, zidovudine, and verapamil, hair discoloration with mephenesin, and reversals from grey to the original hair color with p-aminobenzoic acid have been reported.

5. Pathological gambling
Not all drug side effects are physical; some drugs can cause people to radically change their behaviours or impulse control. Many patients taking drugs such as pramipexole or ropinirole started noticing behavioural problems that they’d never experienced before like increased sexual urges, unusual urges to gamble, or other intense urges. While seemingly improbable and bizarre, these side effects are real for some and certain patients have won lawsuits against pharmaceutical companies after claiming that the drug lost them thousands of dollars in gambling.

Iva Musa, MPharm /  Junior Pharmacovigilance Associate