[Proton Pump Inhibitor and High-dose Methotrexate: Two Cases Reports]

Area of Science:

• Oncology
• Clinical Pharmacology
• Drug Interactions

Background:

• Methotrexate (MTX) is a vital chemotherapeutic agent for malignancies.
• Proton pump inhibitors (PPIs) are commonly used medications.
• Potential interactions between MTX and PPIs require further investigation.

Observation:

• This review highlights cases of delayed MTX elimination in patients concurrently using PPIs.
• This delayed elimination significantly elevates the risk of MTX-related toxic events.
• Two new clinical cases are presented, further illustrating MTX toxicity in the presence of PPIs.

Findings:

• The co-administration of PPIs with MTX can lead to delayed methotrexate clearance.
• This interaction increases the potential for severe adverse drug reactions and methotrexate toxicity.
• The risk appears more pronounced with higher MTX dosages, but caution is advised even for lower doses.

Implications:

• Healthcare providers should carefully evaluate the necessity of PPIs before initiating MTX therapy.
• Assessing the risk-benefit ratio of PPI use in MTX-treated patients is essential to mitigate iatrogenic risks.
• Further research is warranted to establish clear guidelines on the concurrent use of PPIs and MTX.