tetracyclineclass

Tetracyclines are a class of broad-spectrum antibiotics that share a common four-ring chemical structure. They function by inhibiting bacterial protein synthesis by binding to the 30S ribosomal subunit, preventing the attachment of transfer RNA. This action is bacteriostatic, meaning it stops bacterial growth rather than killing bacteria directly. Tetracyclines are effective against a wide range of Gram-positive and Gram-negative bacteria, as well as some atypical organisms like Mycoplasma and Chlamydia. They have also been used to treat certain protozoan infections.

Examples of tetracyclines include tetracycline itself, oxytetracycline, chlortetracycline, demeclocycline, doxycycline, and minocycline. Doxycycline and minocycline are often preferred due to their longer half-lives and better absorption, allowing for less frequent dosing. Resistance to tetracyclines can develop in bacteria through various mechanisms, including efflux pumps that remove the drug from the cell and ribosomal protection proteins that prevent the tetracycline from binding.

Common side effects of tetracyclines include gastrointestinal upset such as nausea and diarrhea, and photosensitivity, which increases the risk of sunburn. Tetracyclines are generally contraindicated in pregnant women and young children because they can cause permanent tooth discoloration and affect bone growth. They are typically administered orally, though some formulations are available for intravenous or topical use. Due to the increasing prevalence of antibiotic resistance, the use of tetracyclines is often guided by susceptibility testing.