Tetracycline is a broad-spectrum antibiotic whose oral absorption and therapeutic efficacy are significantly influenced by concurrent intake of certain foods and medications. The presence of divalent and trivalent cations such as calcium, iron, magnesium, aluminium, and zinc—commonly found in dairy products, mineral supplements, antacids, and fortified foods—leads to chelation with tetracycline, forming insoluble complexes that markedly reduce gastrointestinal absorption. Heavy or fatty meals may further delay absorption. To optimize bioavailability, tetracycline is recommended to be administered on an empty stomach, ideally 1 hour before or 2 hours after meals and mineral-containing products. In addition to food interactions, tetracycline may interact with several drugs, including oral contraceptives (reducing contraceptive efficacy), anticoagulants like warfarin (enhancing anticoagulant effects), penicillin antibiotics (antagonistic action), and retinoids (increasing the risk of intracranial hypertension). Awareness and appropriate management of these interactions are essential to ensure safe and effective tetracycline therapy.
C. Santhoshini*1, Mr. S. Pravin Kumar2, G. Poonguzhali1, S. Tharun Kumar1, M. Deepak Kumar1, G. Kathirvel1 (Mon,) studied this question.