Which drugs may cause photosensitivity and should prompt sun avoidance?

Which drugs may cause photosensitivity and should prompt sun avoidance?

• A. Penicillins
• B. Macrolides
• C. Sulfonamides, fluoroquinolones and tetracyclines
• D. Antacids

Answer: (C)

The main idea is that certain drugs can make the skin react badly to sunlight, causing a phototoxic reaction that looks like an exaggerated sunburn after UV exposure. The classic culprits are sulfonamides, fluoroquinolones, and tetracyclines. These antibiotic classes are well known for causing photosensitivity—drug molecules absorb UV light and generate reactive species that damage skin cells, so sun exposure can trigger rashes, burning, or intensified tanning even with normal UV exposure. Because of this risk, patients are advised to avoid direct sun, wear protective clothing, and use sunscreen while taking these medications. Penicillins and macrolides can be associated with photosensitivity in some cases, but it’s not as common or predictable as with the three classes listed. Antacids don’t typically cause photosensitivity.

The main idea is that certain drugs can make the skin react badly to sunlight, causing a phototoxic reaction that looks like an exaggerated sunburn after UV exposure. The classic culprits are sulfonamides, fluoroquinolones, and tetracyclines. These antibiotic classes are well known for causing photosensitivity—drug molecules absorb UV light and generate reactive species that damage skin cells, so sun exposure can trigger rashes, burning, or intensified tanning even with normal UV exposure. Because of this risk, patients are advised to avoid direct sun, wear protective clothing, and use sunscreen while taking these medications.

Penicillins and macrolides can be associated with photosensitivity in some cases, but it’s not as common or predictable as with the three classes listed. Antacids don’t typically cause photosensitivity.