Alendronate, absorption

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... 

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. 

In other studies, bisphosphonate-pamidronate or alendronate were linked to the terminal carboxylic acid of the stabilized dipeptide Pro-Phe to improve the bioavailability of bisphosphonates by hPepTl-mediated absorption. In-situ single-pass perfused rat intestine studies revealed competitive inhibition of transport by Pro-Phe, suggesting carrier-mediated transport. Oral administration of the dipeptidyl prodrugs resulted in a 3-fold increase in drug absorption following oral administration to rats. The authors suggested that oral bioavailability of bisphosphonates may be improved by PepTl-mediated absorption when administered as peptidyl prodrugs [53]. Future mechanistic studies may prove if hPepTl is involved in the absorption process. 

The oral absorption of an entirely different class of drugs, namely bisphosphonates, has also been improved by a peptide prodrug strategy [36]. The drugs pamidronate (6.13, n=2) and alendronate (6.13, n=3) were deriv-atized with the Pro-Phe-dipeptidyl unit to yield the prodrugs Pro-Phe-pamidronate (6.14, n=2) and Pro-Phe-alendronate (6.14, n=3), the ob-... 

Q71 Patients receiving alendronic acid tablets should be advised to swallow tablet whole with plenty of water. Absorption of alendronic acid is increased leading to higher frequency of side-effects if tablet is swallowed with drinks containing milk. 

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... 

Mrs TY should be advised to take her calcium supplement at a different time of day to her alendronate. Calcium salts can reduce the absorption of alendronate. She should take her alendronate 30 minutes before any medication. She may wish to take her alendronate before breakfast, followed by her first dose of calcium at lunchtime and her second dose of calcium at dinnertime. She should take her alendronate 30 minutes before any medication. She may wish to take her alendronate on rising followed by her first dose of calcium at least half an hour later or she may wish to take her alendronate before breakfast, followed by... 

Milk and dairy foods decrease the absorption of some tetracyclines (doxycycline and minocycline are not affected), some quinolone antibiotics (absorption of ciprofloxacin and norfloxacin is decreased but ofloxacin is not affected), penicillamine and alendronate. Large volumes of milk can reduce the ulcer-healing properties of bismuth tripotassium dicitratobismuthate (bismuth chelate),... 

Bisphosphonates pamidronate and alendronate (the most active bisphos-phonates approved for clinical use) were converted into the peptidyl prodrugs prolyl-phenylalanylpamidronate [Pro-Phe-pamidonate (420)] and prolyl-phenylalanyl-alendronate [Pro-Phe-alendronate (421)]. It was shown that the bioavailability of bisphosphonates can be enhanced by using the peptide prodrug approach. The increased oral absorption of the prodrugs was reduced by an active carrier-mediated transport. ... 

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. 

Alendronate and risedronate. These dru are taken with 6 to 8 oz of water first thing in tlie morning. Do not lie down for at least 30 minutes after taking the drug and wait at least 30 minute before taking any other food or drink. The dru are taken exactly as pr jciibed. The primary care provider may prescribe alendronate as a once weekly dose or to be taken daily. Risedronate is taken daily. Take supplemental calcium and vitamin D if dietary intake is inadequate Take all medication, including vitamin and mineral supplements, at a different time of the day to prevent interference with absorption of the drug. 

The manufacturers of alendronate suggest that, in order to avoid absorption interactions, patients should wait at least 30 minutes after taking alendronate before taking any other drug or food, and that alendronate should be taken with plain water only. 

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