Used primarily as a broad-spectrum antibiotic in the treatment of bacterial infections, particularly those caused by susceptible strains of gram-positive and gram-negative bacteria. Commonly prescribed for respiratory tract infections, urinary tract infections, acne, and certain sexually transmitted infections like chlamydia. Also effective in managing rickettsial diseases and as an alternative in patients allergic to penicillin. Its mechanism involves inhibition of bacterial protein synthesis by binding to the 30S ribosomal subunit. Due to its tetracycline structure, it may be used in cases where other antibiotics are not suitable, though resistance can limit its effectiveness.