Antacids Alendronate

When administered with ranitidine, alendronate bioavailability is increased. When calcium supplements or antacids are administered with risedronate or alendronate, absorption of the bisphosphonates is decreased, hi addition, risedronate absorption is inhibited when the drug is administered with magnesium and aluminum. There is an increased risk of gastrointestinal... 

BISPHOSPHONATES. When administering alendronate or risedronate the nurse gives the drug orally in the morning before the first food or drink of the day. Risedronate and etidronate are administered once daily. Etidronate is not administered within 2 hours of food, vitamin and mineral supplements, or antacids. 

Uses Rx prevent osteoporosis male female, Rx steroid-induced osteoporosis, Paget Dz Action -1- N1 abnormal bone resorption Dose Osteoporosis Rx 10 mg/d PO or 70 mg qwk Fosamax plus D 1 tab qwk Steroid-induced osteoporosis Rx 5 mg/d PO Prevention 5 mg/d PO or 35 mg qwk Paget Dz 40 mg/d PO Caution [C, ] Not OK if CrCl <35 mLAnin, w/ NSAID use Contra Esophageal anomalies, inability to sit/stand upright for 30 min, X Ca Disp Tabs, soln SE GI disturbances, esophageal irritation, HA, pain, jaw osteonecrosis (w/ dental procedures, chemo) Interactions -1- Absorption W7 antacids, Ca supls, Fe, food T risk of upper GI bleed W/ ASA NSAIDs EMS May cause cardiac conduction abnormalities d/t T Ca T risk of jaw fractures esp w/ dental procedures OD May cause hypocalcemia and adverse upper-GI effects milk or antacids can be given to bind alendronate... 

Alendronate absorption is reduced by antacids, calcium salts and iron. Concurrent use with aminoglycosides may lead to hypocalcaemia. Patients should be told to take alendronate 30 minutes before food and other medication. 

Alendronate sodium (10 mg/day) is indicated for the treatment of osteoporosis in postmenopausal women and of Paget s disease. It acts as a specihc inhibitor of osteoclast-mediated bone resorption. The osteoclasts adhere normally to the bone surface but lack the ruffled border that is indicative of active resorption. Alendronate does not interfere with osteoclast recruitment or attachment, but it does inhibit osteoclast activity. Bones examined 6 and 49 days after ( H)alendronate administration showed that normal bone was formed on top of the alendronate, which was incorporated in bone matrix. Alendronate is not pharmacologically active thus, it must be continuously administered to suppress osteoclasts on newly formed resorption surfaces. Calcium supplements, antacids, and other oral medications will interfere with absorption of Fosamax. Therefore, patients must wait at least one hour before taking Fosamax. 

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