Which of the following is a common side effect of tetracyclines?

Tetracyclines are a class of antibiotics that are widely used to treat various infections, particularly those caused by atypical organisms such as Chlamydia and Rickettsia, as well as some skin conditions like acne. A well-known side effect associated with this class of drugs is photosensitivity, which can lead to increased skin sensitivity to sunlight and a higher risk of sunburn. Patients taking tetracyclines are often advised to take precautions when exposed to sunlight or ultraviolet light, as this can lead to adverse skin reactions.

Photosensitivity occurs because tetracyclines can absorb UV light, which leads to skin reactions when the skin is subsequently exposed to sunlight. This side effect is specifically common among doxycycline and minocycline, two commonly used tetracyclines.

The other options present potential side effects of different medications or conditions rather than of tetracyclines. Stomach ulcers and nephrotoxicity are not commonly associated with this class of antibiotics, and while skin rashes can occur with many medications, they are not as specifically linked to tetracyclines as photosensitivity is. Therefore, recognizing photosensitivity as a key side effect underscores the importance of patient education on sun protection while on tetracycline therapy.