Foods Bisphosphonates

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. 

Oral bisphosphonates are poorly absorbed (less than 5%). Taking them in the presence of food or calcium supplementation further reduces absorption. After absorption, bisphosphonate uptake to the primary site of action is rapid and sustained. Once attached to bone tissue, bisphosphonates are released very slowly. These drugs are not metabolized and are excreted renally. They are not recommended for use in patients with renal insufficiency. 

Bonviva consists of ibandronic acid, a bisphosphonate and is available as 150 mg tablets and 1 mg/mL injection. Patients receiving the oral formulation for the treatment of postmenopausal osteoporosis are advised to take one tablet once a month. Absorption of bisphosphonates from the gastrointestinal tract may be effected by food or other administered drugs. Therefore patients are advised to take the Bonviva 150 mg tablet at least 1 hour before breakfast or another oral medicine and to continue standing or sitting upright for at least 1 hour after administration. 

A. Pharmacokinetics Pamidronate is administered intravenously. All of the other bisphosphonates are orally active, although less than ten percent of the administered dose is absorbed. Food significantly interferes with absorption. Bisphosphonates should be administered with six to eight ounces of water at least one hour before eating breakfast. The bisphosphonates are rapidly cleared from the plasma, primarily because they avidly bind to hydroxyapatite mineral of bone. Once bound to bone they are cleared over a period of months to years. Elimination from the body is solely through renal clearance, and the bisphosphonates should not be given to individuals with severe renal impairment. 

Bisphosphonates - must be taken on an empty stomach as they chelate with metal ions in food. Available as daily, weekly or monthly formulations to improve compliance. Increases bone mass by 3% per year when given in conjunction with calcium and vitamin D. 

In a retrospective analysis of spontaneous adverse event reports encompassing more than 430, 000 patients who had received zoledronic acid between August 2001 and March 2003, only 72 cases of renal failure were identified by the US Food and Drug Administrahon [78, 79]. It should be noted, however, that patients with risk factors for renal deterioration, including advanced cancer, previous bisphosphonate exposure, and use of nonsteroidal anti-inflammatory medications, may have contributed to the progression of renal failure [79]. Because of the potentially serious nature of this adverse event, it is recommended to monitor renal funchon in patients with cancer before each infusion of zoledronic acid, provide adequate hydration, and modify or discontinue treatment if renal complications occur [30, 78, 79]. 

I Administration. Even under optimal conditions, all bisphosphonates are poorly absorbed (bioavailabihty = 1% to 5%). Bisphosphonates must be administered carefully to optimize the chnical benefit and minimize the risk of adverse G1 effects. Each oral tablet should be taken with at least 4 ounces of plain tap water (not coffee, juice, mineral water, or milk) at least 30 minutes before consuming any food or any other supplement or medication. The weekly oral solution needs to be taken with only 2 ounces of water. The patient should remain upright (either sitting or standing) for at least 30 minutes after bisphosphonate administration. When calcium and vitamin D dietary consumption are insufficient, supplementation is needed to ensme the beneficial effects of bisphosphonates. 

Hormone] Uses Paget Dz Rx/ prevent glucocordcoid-induced/postmenopausal osteopoi osis Action Bisphosphonate X osteoclast-mediated bone i esoiption Dose Paget Dz 30 mg/d PO for 2 mo Osteoporosis Rx/prevention 5 mg daily or 35 mg qwk 30 min befoi e 1st food/drink of the day stay upright for at least 30 min after Caution [C, /-] Ca supls antacids X absorption Contra Component allei y, X Ca, esophageal abnormalities, unable to stand/sit for 30 min, CrCl <30 mL/min... 

Paget s disease (Table 35.6) is characterized by excessive bone resorption, followed by replacement of the normally mineralized bone with soft, poorly mineralized tissue (20). It has been determined that the osteoclasts have an abnormal structure, are hyperactive, and are present at elevated levels (20). Patients afflicted with this painful condition often suffer from multiple compression fractures. Administration of calcitonin and oral calcium and phosphate supplements had been the treatment of choice until the bisphosphonate risedronate was approved by the U.S. Food and Drug Administration (FDA). Daily administration of risedronate results in a decreased rate of bone turnover and a decrease in the levels of serum alkaline phosphatase and urinary hydroxyproline, two biochemical markers of bone turnover (4,20). A significant advantage to treatment with the bisphosphonates is long-term suppression of the disease (20). Calcium supplementation, which often is necessary in these patients, must be dosed separately from risedronate, because calcium- and aluminum- or... 

Recommendations on the timing of administration of bisphosphonates in relation to food and other drugs varies. 

The oral absorption of bisphosphonates is reduced by Maalox and by other antacids, calcium-rich foods, calcium supplements, iron preparations, magnesium-containing laxatives or milk. 

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