Welcome to the FDA Side Effects Update. This series is designed to keep you informed about the latest safety advisories and newly documented side effects of your medications. In this installment, we’re highlighting safety updates concerning these drugs used to treat osteoporosis: Actonel, Atelvia, Binosto, Fosamax, Fosamax Plus D, Reclast, and Ibandronate Sodium (Boniva generic).

Updated Side Effect Warnings for Bisphosphonate Osteoporosis Drugs

Bisphosphonates are commonly prescribed to treat osteoporosis and Paget’s disease of bone, a condition marked by excessive bone breakdown followed by abnormal regrowth. Both disorders most often affect people over age 50.

In osteoporosis, bone is broken down faster than it can be rebuilt, leaving bones fragile and more prone to fractures. Bisphosphonates work by slowing this bone loss, helping to preserve bone strength.

While bisphosphonates have been shown to reduce the number of hip and pelvis fractures in patients over time, reports of spontaneous fractures in the thigh, called “atypical femur fractures,” have emerged over the years. These are fractures that happen without trauma or injury and are preceded by bone pain in the days or weeks before a complete fracture of the bone occurs.

In 2010, the FDA issued a safety communication and new drug label warning about the risk of atypical femur fractures associated with bisphosphonates. Following those safety concerns, use of bone medications — primarily bisphosphonates — declined sharply, falling from about 11% of women over age 50 in 2007 to just 5% in 2018.

In recent years, reports of spontaneous fractures in areas other than the femur have increased. In 2024, the American Society for Bone and Mineral Research published a research review of studies involving “atypical fractures at non-classical sites” associated with bisphosphonate use. The most frequent atypical fracture sites were the ulna (hand) and tibia (lower leg).

In response to these reports of atypical fractures, the FDA is updating the labels of bisphosphonate medications to warn that “atypical” fractures can happen in other bones, not just the femur. The fractures might be “bilateral,” or occur in the same bones on both sides of the body. The labels also note that atypical femur fractures can occur in people with osteoporosis who have not taken bisphosphonates, and that taking glucocorticoids such as prednisone at the same time may increase the risk.

Generic medications that are considered “reference drugs” for the products listed here, meaning they contain the same ingredients and formulation, will carry the same side effect updates.

Actonel (risedronate sodium) tablets

Initial FDA Approval: 1998
Side Effect Update Date: February 3, 2026
Medication Description: Treats and prevents osteoporosis in postmenopausal women; treats osteoporosis in men; treats Paget’s disease of the bone. Works by slowing down the rate of bone loss.
Updated Side Effects/Safety Information: A new warning describes “atypical” fractures that can occur in the thigh bone (femur) and other bones, often after little or no trauma. Glucocorticoids (like prednisone) may increase the risk. Symptoms experienced in the days or weeks before an atypical fracture include new, dull pain in the thigh, hip, groin, or other bone areas. Patients experiencing these symptoms should be evaluated by their health care provider. If a fracture is detected, discontinuation or interruption of treatment should be considered. 

FDA Safety Announcement: Actonel Safety Label Change and Revised Label

Atelvia (risedronate sodium) delayed‑release tablets

Initial FDA Approval: 2010
Side Effect Update Date: February 2, 2026
Medication Description: Treats osteoporosis in postmenopausal women. Works by slowing down the rate of bone loss.
Updated Side Effects/Safety Information: A new warning describes “atypical” fractures that can occur in the thigh bone (femur) and other bones, often after little or no trauma. Glucocorticoids (like prednisone) may increase the risk. Symptoms experienced in the days or weeks before an atypical fracture include new, dull pain in the thigh, hip, groin, or other bone areas. Patients experiencing these symptoms should be evaluated by their health care provider. If a fracture is detected, discontinuation or interruption of treatment should be considered.  

FDA Safety Announcement: Atelvia Safety Label Change and Revised Drug Label

Binosto (alendronate sodium) effervescent tablet

Initial FDA Approval: 2012
Side Effect Update Date: February 3, 2026
Medication Description: Treats osteoporosis in men and postmenopausal women. Works by slowing down the rate of bone loss. This medication is a strawberry-flavored effervescent tablet that is dissolved in a glass of water.
Updated Side Effects/Safety Information A new warning describes “atypical” fractures that can occur in the thigh bone (femur) and other bones, often after little or no trauma. Glucocorticoids (like prednisone) may increase the risk. Symptoms experienced in the days or weeks before an atypical fracture include new, dull pain in the thigh, hip, groin, or other bone areas. Patients experiencing these symptoms should be evaluated by their health care provider. If a fracture is detected, discontinuation or interruption of treatment should be considered.  

FDA Safety Announcement: Binosto Safety Label Change and Revised Drug Label

Fosamax (alendronate sodium) tablets

Initial FDA Approval: 1995
Side Effect Update Date: February 3, 2026
Medication Description: Treats and prevents osteoporosis in postmenopausal women; treats osteoporosis in men; treats Paget’s disease of the bone. Works by slowing down the rate of bone loss.
Updated Side Effects/Safety Information: A new warning describes “atypical” fractures that can occur in the thigh bone (femur) and other bones, often after little or no trauma. Glucocorticoids (like prednisone) may increase the risk. Symptoms experienced in the days or weeks before an atypical fracture include new, dull pain in the thigh, hip, groin, or other bone areas. Patients experiencing these symptoms should be evaluated by their health care provider. If a fracture is detected, discontinuation or interruption of treatment should be considered.  

FDA Safety Announcement: Fosamax Safety Label Change and Revised Drug Label

Fosamax Plus D (alendronate sodium and cholecalciferol) tablets

Initial FDA Approval: 2005
Side Effect Update Date: February 3, 2026
Medication Description: Treats osteoporosis in men and postmenopausal women. Contains the bisphosphonate alendronate sodium combined with vitamin D3.  Works by slowing down the rate of bone loss.
Updated Side Effects/Safety Information: A new warning describes “atypical” fractures that can occur in the thigh bone (femur) and other bones, often after little or no trauma. Glucocorticoids (like prednisone) may increase the risk. Symptoms experienced in the days or weeks before an atypical fracture include new, dull pain in the thigh, hip, groin, or other bone areas. Patients experiencing these symptoms should be evaluated by their health care provider. If a fracture is detected, discontinuation or interruption of treatment should be considered.  

FDA Safety Announcement: Fosamax Plus D Safety Label Change and Revised Drug Label

Ibandronate sodium tablets and injection (Boniva generic; Boniva brand has been discontinued)

Initial FDA Approval: 2003
Side Effect Update Date (Label): January 15, 2026
Medication Description: Injection is administered intravenously every three months and treats osteoporosis in postmenopausal women. Tablets are taken monthly and treat and prevent osteoporosis in postmenopausal women. Works by slowing down the rate of bone loss.
Updated Side Effects/Safety Information: A new warning describes “atypical” fractures that can occur in the thigh bone (femur) and other bones, often after little or no trauma. Glucocorticoids (like prednisone) may increase the risk. Symptoms experienced in the days or weeks before an atypical fracture include new, dull pain in the thigh, hip, groin, or other bone areas. Patients experiencing these symptoms should be evaluated by their health care provider. If a fracture is detected, discontinuation or interruption of treatment should be considered.  

Revised Drug Label for ibandronate sodium (injection) by Apotex
Revised Drug Label for ibandronate sodium (tablets) by MacLeod
Other generic makers of ibandronate sodium will have similar updates.  FDA Safety Label Change updates are not yet available. 

Reclast (zoledronic acid) injection

Initial FDA Approval: 2007
Side Effect Update Date: February 3, 2026
Medication Description: Treats or prevents osteoporosis in postmenopausal women; treats osteoporosis in men; treats Paget’s disease of the bone in men and women. Delivered by intravenous (IV) infusion, usually once a year or every other year for prevention. Works by slowing down the rate of bone loss.
Updated Side Effects/Safety Information: A new warning describes “atypical” fractures that can occur in the thigh bone (femur) and other bones, often after little or no trauma. Glucocorticoids (like prednisone) may increase the risk. Symptoms experienced in the days or weeks before an atypical fracture include new, dull pain in the thigh, hip, groin, or other bone areas. Patients experiencing these symptoms should be evaluated by their health care provider. If a fracture is detected, discontinuation or interruption of treatment should be considered.  

FDA Safety Announcement: Reclast Safety Label Change and Revised Drug Label

1. Research, C. F. D. E. A. (2018, February 6). FDA Drug Safety Communication: Safety update for osteoporosis drugs, bisphosphonates, and atypical fractures. U.S. Food And Drug Administration.
2. Collins, L., Ronan, A., Hutcheon, E., Ebeling, P. R., Grill, V., & Nguyen, H. H. (2024). Atypical fractures at non-classical sites associated with anti-resorptive therapy: a systematic review. Journal of Bone and Mineral Research, 39(12), 1722–1734.
3. National Library of Medicine. (n.d.). Paget’s Disease of Bone. MedlinePlus.
4. National Library of Medicine. (n.d.). Steroids.