Drug interactions between capecitabine and Flagyl ER
| Results for the following 2 drugs: |
|---|
| capecitabine |
| Flagyl ER (metronidazole) |
Interactions between your selected drugs
metronidazole ↔ capecitabine
Applies to:Flagyl ER (metronidazole) and capecitabine
GENERALLY AVOID: Coadministration with a nitroimidazole may increase the toxicity of 5-fluorouracil (5-FU). The interaction has been observed with both metronidazole and misonidazole. The proposed mechanism involves reduced clearance of 5-FU in the presence of nitroimidazoles. In a study of 27 patients with metastatic colorectal cancer who received metronidazole (750 mg/m2 IV) an hour before 5-FU (600 mg/m2 IV) on five consecutive days per week every 4 weeks, an unusually high incidence of fluorouracil toxicity was observed, including granulocytopenia (74%), anemia (41%), stomatitis and oral ulceration (34%), nausea and vomiting (48%), and thrombocytopenia (19%). In another study, 15 patients receiving 5-FU (1 gm/m2) with misonidazole 2 gm/m2 or 3 gm/m2 for advanced colorectal cancer had an increased incidence (44% and 56%, respectively) and severity of nausea and vomiting compared to administration of 5-fluorouracil alone (27%) in a prior course. The incidence of leukopenia was also higher with the combination than 5-FU alone (18% versus 13%), although the difference was not statistically significant. Despite an increase in toxicity, in vitro studies performed by the first group of investigators failed to detect any additive or synergistic antineoplastic effect secondary to the interaction.
MANAGEMENT: Given the potential for increased toxicity, 5-fluorouracil and its prodrugs, capecitabine and tegafur, should probably not be used with nitroimidazoles unless benefits are anticipated to outweigh the risks.
See also...
Drug Interaction Classification
The classifications below are a guideline only. The relevance of a particular drug interaction to a specific patient is difficult to determine using this tool alone given the large number of variables that may apply.
| Major | Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit. |
| Moderate | Moderately clinically significant. Usually avoid combinations; use it only under special circumstances. |
| Minor | Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan. |
Do not stop taking any medications without consulting your healthcare provider.
Disclaimer: Every effort has been made to ensure that the information provided by Multum is accurate, up-to-date, and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. Multum's drug information does not endorse drugs, diagnose patients, or recommend therapy. Multum's drug information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill , knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug of drug combination is safe, effective, or appropriate for any given patient. Multum Information Services, Inc. does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. Copyright 2000-2012 Multum Information Services, Inc. The information in contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse, or pharmacist.
