Drug Interaction Report

GENERALLY AVOID: Because irinotecan has been reported to cause diarrhea in the majority of treated patients, the use of laxatives may not be appropriate during irinotecan therapy.

MANAGEMENT: In patients requiring laxatives for constipation associated with narcotic administration, the standard regimen may be continued under supervision of the clinician. However, patients should be advised to inform their physician of any changes in their bowel habit so that dosage adjustments or discontinuation of laxatives may be done promptly.

ADJUST DOSING INTERVAL: Administration with food may increase the absorption of calcium. However, foods high in oxalic acid (spinach or rhubarb), or phytic acid (bran and whole grains) may decrease calcium absorption.

MANAGEMENT: Calcium may be administered with food to increase absorption. Consider withholding calcium administration for at least 2 hours before or after consuming foods high in oxalic acid or phytic acid.