Cycline

Cycline is a term encountered primarily in pharmacology as the suffix in several antibiotic names, rather than a distinct chemical entity. It is part of the naming convention for many drugs in the tetracycline family, including doxycycline and minocycline, as well as older agents such as tetracycline. The word "cycline" in drug names signals a relation to this class of broad-spectrum antibiotics.

Tetracyclines are bacteriostatic antibiotics that inhibit bacterial protein synthesis by binding to the 30S ribosomal subunit. They have a wide spectrum of activity against Gram-positive and Gram-negative bacteria and are used for conditions such as acne, sexually transmitted infections, atypical organisms (Rickettsia, Chlamydia), pneumonia, and tick-borne diseases. Doxycycline and minocycline are among the most commonly prescribed members today, while tetracycline is used less frequently due to side effects like photosensitivity and dental staining in children.

Safety and pharmacology: Tetracyclines can interact with calcium and magnesium, reducing absorption if taken with dairy products or antacids; they should be avoided in pregnancy and early childhood due to effects on fetal and teeth development. Some derivatives offer improved tissue penetration and longer half-lives. In modern medicine, the suffix "-cycline" continues to appear in drug names but does not denote a single compound; instead it identifies a member of the tetracycline family or a related derivative.