Short answer: There is no fixed end date. The Fosamax, Actonel, ibandronate and Reclast labels all say the best length of treatment has not been worked out, that the need to keep going should be checked from time to time, and that people at low risk of a fracture can be considered for stopping after 3 to 5 years. Whether that applies to you is a call for your prescriber, who looks at your fracture risk.
Each oral and IV bisphosphonate label has a "limitations of use" line in section 1. The Fosamax label (section 1.6) says the optimal duration of use has not been determined, and that the evidence for treating osteoporosis rests on clinical data of four years. It says everyone on bisphosphonate therapy should have the need for continued therapy re-evaluated on a periodic basis, that patients at low risk for fracture should be considered for stopping after 3 to 5 years, and that people who stop should have their fracture risk re-checked periodically.
| Medicine | Section | What it says |
|---|---|---|
| Fosamax (alendronate) | 1.6 | Optimal duration not determined; consider stopping after 3 to 5 years if fracture risk is low; re-check risk after stopping |
| Actonel (risedronate) | 1.5 | Optimal duration not determined; consider stopping after 3 to 5 years if fracture risk is low |
| Ibandronate tablets | 1.2 | Optimal duration not determined; consider stopping after 3 to 5 years if fracture risk is low |
| Reclast (zoledronic acid, yearly IV) | 1.6 | Optimal duration not determined; consider stopping after 3 to 5 years if fracture risk is low |
None of the labels sets an upper limit, and none says everyone should stop at 5 years. The wording is "consider", for people at low risk.
Two rare problems are tied to longer use in the labels. The Fosamax label says the risk of osteonecrosis of the jaw (ONJ) may increase with duration of exposure to bisphosphonates (section 5.4), and it describes atypical thigh bone fractures that have been reported during treatment (section 5.5). Both are covered on their own pages: jaw problems on bone medicines and thigh or groin pain on bone medicines.
Against that sits the reason for treatment: the labels say these medicines lower the chance of spine and, for some, hip fractures in women with osteoporosis.
A drug holiday is a planned break from a bisphosphonate after several years. The phrase is not in the labels, but a 2016 task force of the American Society for Bone and Mineral Research (ASBMR) used it. Its abstract describes two trials of long-term use: women who took alendronate for 10 years had fewer clinical spine fractures than those switched to placebo after 5 years (FLEX), and women given 6 yearly zoledronic acid infusions had fewer spine fractures on x-ray than those switched to placebo after 3 (HORIZON extension).
From those, the task force suggested reassessing risk after 5 years of an oral bisphosphonate or 3 years of an IV one. For women at high risk, such as older women, those with a low hip T-score or a high fracture risk score, a previous major osteoporotic fracture, or a fracture while on treatment, it suggested considering continuing for up to 10 years (oral) or 6 years (IV), with periodic checks. For women not at high risk after 3 to 5 years, it said a holiday of 2 to 3 years can be considered.
The task force noted its approach rests on limited evidence, mostly in white postmenopausal women, and does not replace clinical judgment. It found the risk of atypical femur fracture, but not jaw osteonecrosis, clearly rises with duration.
The 3-to-5-year wording is specific to bisphosphonates, which stay in bone. Other bone medicines have different rules. The Prolia (denosumab) label warns that fracture risk, including multiple spine fractures, rises after stopping, and says people who stop should move to another antiresorptive medicine; see what happens if you stop Prolia. The Evenity label limits use to 12 monthly doses and suggests an antiresorptive afterward if treatment is still needed.
Useful notes for a review visit: the date you started, any missed months, falls or fractures since starting, and your latest bone density result. Dose Track keeps a weekly or monthly reminder and a history of each dose.
Read more on Dose Track: Fosamax side effects · Actonel side effects · Reclast side effects · Missed a Fosamax dose · Prolia vs Forteo