Risedronate resources

Interactions for Risedronate:

No specific drug-drug interaction studies were performed. Risedronate is not metabolized and does not induce or inhibit hepatic microsomal drug-metabolizing enzymes (Cytochrome P450).

Calcium Supplements/Antacids

Co-administration of ACTONEL and calcium, antacids, or oral medications containing divalent cations will interfere with the absorption of ACTONEL.

Hormone Replacement Therapy

One study of about 500 early postmenopausal women has been conducted to date in which treatment with ACTONEL (5 mg/day) plus estrogen replacement therapy was compared to estrogen replacement therapy alone. Exposure to study drugs was approximately 12 to 18 months and the primary endpoint was change in BMD. If considered appropriate, ACTONEL may be used concomitantly with hormone replacement therapy.

Aspirin/Nonsteroidal Anti-Inflammatory Drugs (NSAIDs)

Of over 5700 patients enrolled in the ACTONEL Phase 3 osteoporosis studies, aspirin use was reported by 31% of patients, 24% of whom were regular users (3 or more days per week). Forty-eight percent of patients reported NSAID use, 21% of whom were regular users. Among regular aspirin or NSAID users, the incidence of upper gastrointestinal adverse experiences in ACTONEL-treated patients (24.5%) was similar to that in placebo-treated patients (24.8%).

H₂ Blockers and Proton Pump Inhibitors (PPIs)

Of over 5700 patients enrolled in the ACTONEL Phase 3 osteoporosis studies, 21% used H₂ blockers and/or PPIs. Among these patients, the incidence of upper gastrointestinal adverse experiences in the ACTONEL-treated patients was similar to that in placebo-treated patients.

Drug/Laboratory Test Interactions

Bisphosphonates are known to interfere with the use of bone-imaging agents. Specific studies with ACTONEL have not been performed.