Does tigecycline interact with antacids?
Tigecycline, an antibiotic used for complicated infections, can be taken with antacids. Unlike tetracyclines such as doxycycline or minocycline, tigecycline's absorption is not significantly reduced by antacids containing aluminum, magnesium, or calcium. Its prescribing information states no dosage adjustment is needed when co-administered with antacids.[1]
Why don't antacids affect tigecycline like other tetracyclines?
Traditional tetracyclines form insoluble chelates with divalent or trivalent cations in antacids, cutting absorption by up to 90%. Tigecycline, a glycylcycline derivative, has a modified structure that resists this chelation, maintaining bioavailability around 60% even with antacids.[2][1]
What does the prescribing label say about administration?
Tygacil (tigecycline) label confirms: "Tigecycline may be administered intravenously with antacids." No separation of doses is required, unlike with fluoroquinolones or oral tetracyclines. Take it as a 100 mg IV loading dose followed by 50 mg every 12 hours.[1]
Are there any timing concerns or exceptions?
No specific timing restrictions exist for antacids. However, tigecycline is IV-only, so oral antacids pose no direct interference. Avoid if using enteral nutrition with high cation content, as it may slightly lower exposure—monitor clinically.[1][3]
What other drugs or foods should patients watch for?
Dairy, multivitamins, or cation-rich supplements have minimal impact. Warfarin may prolong INR; monitor levels. No major food interactions reported.[1]
[1]: Tygacil Prescribing Information (Pfizer)
[2]: Clinical Pharmacology Review - Tigecycline (FDA)
[3]: Lexicomp Drug Interactions - Tigecycline