Allopurinol and Capecitabine interaction
Allopurinol and Capecitabine: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Allopurinol label · effective 2026-05-21
Capecitabine: Avoid concomitant use.
Intervention Avoid the use of allopurinol tablets during treatment with capecitabine Chlorpropamide Clinical Impact Allopurinol tablets prolongs the half-life of chlorpropamide as both compete for renal tubular excretion.
Drugs Known to Have Clinically Important Drug Interactions with Allopurinol Tablets Table 3: Interventions for Clinically Important Drug Interactions with Allopurinol Tablets Capecitabine Clinical Impact Concomitant use with allopurinol may decrease concentration of capecitabine’s active metabolites, which may decrease capecitabine efficacy.
From the Capecitabine (XELODA) label · effective 2026-02-05
Allopurinol: Avoid concomitant use of allopurinol with XELODA.
Avoid concomitant use of allopurinol with XELODA.
Effect of Other Drugs on XELODA Allopurinol Concomitant use with allopurinol may decrease concentration of capecitabine's active metabolites [see Clinical Pharmacology (12.3) ] , which may decrease efficacy.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.