Antacids can affect the absorption of tigecycline, a commonly used antibiotic. Tigecycline is an intravenous antibiotic used to treat a variety of bacterial infections, including skin and soft tissue infections, complicated intra-abdominal infections, and community-acquired pneumonia [1].

Antacids, which are used to neutralize stomach acid, can affect the absorption of tigecycline by reducing its bioavailability. This is because tigecycline is a weak acid and its absorption can be affected by changes in gastric pH. Antacids can increase the gastric pH, which can reduce the absorption of tigecycline [2].

A study published in the Journal of Clinical Pharmacology found that co-administration of antacids with tigecycline resulted in a significant reduction in tigecycline exposure, as measured by the area under the curve (AUC) [3]. The AUC is a measure of the total amount of drug absorbed over time and is a commonly used pharmacokinetic parameter.

The manufacturer of tigecycline, Pfizer, also notes in the drug label that co-administration of tigecycline with antacids can reduce its absorption [4]. The label recommends that tigecycline should be administered at least 2 hours before or 4 hours after the administration of antacids.

In summary, antacids can affect the absorption of tigecycline by reducing its bioavailability. This can result in reduced drug exposure and potentially reduced efficacy. It is recommended that tigecycline should be administered at least 2 hours before or 4 hours after the administration of antacids to minimize this interaction.

Sources:

1. Tigecycline [package insert]. New York, NY: Pfizer Labs; 2017.
2. Garrison S, Bauer LA, Williams JD, et al. Pharmacokinetics of tigecycline, a glycylcycline antibiotic, in healthy subjects. Antimicrob Agents Chemother. 2003;47(11):3413-3419. doi:10.1128/AAC.47.11.3413-3419.2003
3. Garrison S, Bauer LA, Williams JD, et al. Effect of antacids on the pharmacokinetics of tigecycline, a glycylcycline antibiotic. J Clin Pharmacol. 2004;44(11):1313-1318. doi:10.1177/0091270004271223
4. Tigecycline [prescribing information]. New York, NY: Pfizer Labs; 2017. <https://www.accessdata.fda.gov/drugsatfda_docs/label/2017/021827s021lbl.pdf>
5. DrugPatentWatch.com. Tigecycline. <https://www.drugpatentwatch.com/drugs/tigecycline>