Drug Interaction Report

ADJUST DOSING INTERVAL: Coadministration with antacids, mineral supplements, or other medications containing polyvalent cations such as magnesium, aluminum, calcium, and iron may decrease the bioavailability of oral cabotegravir. The proposed mechanism involves chelation of cabotegravir by polyvalent cations, forming a complex that is poorly absorbed from the gastrointestinal tract. The interaction has not been studied with cabotegravir, but has been reported with other integrase strand transfer inhibitors (INSTIs).

MANAGEMENT: To minimize the risk of reduced viral susceptibility and resistance development associated with subtherapeutic levels of cabotegravir, medications containing polyvalent cations such as antacids and mineral supplements should be administered at least 2 hours before or 4 hours after the oral cabotegravir dose.

ADJUST DOSING INTERVAL: Products containing aluminum, calcium, magnesium and other polyvalent cations such as antacids or vitamin with mineral supplements are likely to interfere with the gastrointestinal absorption of oral bisphosphonates. For example, the bioavailability of tiludronate has been shown to decrease 80% during simultaneous administration with calcium, and 60% when aluminum- or magnesium-containing antacids were administered one hour before tiludronate.

MANAGEMENT: Antacids or other oral medications containing aluminum, calcium, magnesium and other polyvalent cations should be administered at least 30 minutes after the bisphosphonate dose.

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.

ADJUST DOSING INTERVAL: Food significantly decreases the bioavailability of risedronate, possibly to negligible levels.

MANAGEMENT: Risedronate should be administered with 180 to 240 mL (6 to 8 ounces) of plain water, at least 30 minutes before the first food, beverage, or medication of the day. Patients should remain upright for at least 30 minutes following administration of risedronate.