Fosamax Side Effects and History


Fosamax® (alendronate sodium) is one of the bisphosphonates used to treat osteoporosis, and it's been in use since 1995. Since this drug has been on the market the longest, we have more long-term data on its precautions and warnings.

Many of our members ask questions about this drug so we wanted to explain its risks and benefits.

Fosamax Side Effects

Abdominal pain







Acid regurgitation

Abdominal distention


Esophageal ulcer


Musculoskeletal pain



Muscle cramp

Taste perversion

(Rarely) uveitis


Gastroesophgeal reflux

(Rarely) scleritis   [1]

Adverse side effects above were reported in ≥ 1% of patients treated with Fosamax [1]

Pre-administration tests and conditions

Fosamax is not recommended in patients who have kidney disease or a creatinine clearance test of Ë‚ 35 mL/min. Hypocalcemia (low blood calcium) must be corrected before administration of Fosamax. Patients that have suffered a non-traumatic femoral fracture (thigh bone) or osteonecrosis of the jaw should discuss discontinuation of this treatment with their health care provider.

If you are considering taking Fosamax, be sure your doctor checks your serum calcium levels, creatinine clearance test, screens for prior kidney disease, femur fracture and malabsorption problems. Patients who experience esophageal problems such as difficulty or pain while swallowing and new or worsening heartburn, should reconsider taking Fosamax. All of the above are contraindicated with Fosamax.

Fracture Studies on Fosamax

In the Three-Year Fit Study fractures were reduced from 15.0% to 7.9%; and in the Four-Year Fit Study the percentages of fracture reduction went from 3.8% to 2.1%. [1]

Emerging Safety Warnings on Fosamax and Other Bisphosphonates

  • Osteonecrosis of the jaw
  • Atypical subtrochanteric femoral fractures
  • Link to esophageal cancers
  • Musculoskeletal pain
  • Atrial fibrillation

Bisphosphonates include: Fosamax ® (alendronate sodium), Fosamax with D ®, Actonel ® (risedronate sodium), Actonel with Calcium ®, Atelvia ® (risedronate sodium), Reclast ® (zoledronic acid) and Boniva ® (ibandronate sodium).

Osteonecrosis of the jaw is a condition that develops in the oral cavity due to the use of these drugs. "A condition that may develop in patients on bisphosphonate therapy in which pain, swelling and infection of soft tissue, drainage, loosening of teeth, and exposed bone may occur suddenly, usually at a previous tooth extraction site, as well as numbness and heaviness of the jaw." [2] Necrosis (death of the bone) occurs due to the obstruction of its blood supply.

Cancer patients receiving concomitant chemotherapy, corticosteroids and potent intravenous bisphosphonates, like Zometa® (zoledronic acid), are at a higher risk of contraction of osteonecrosis of the jaw due to a loss of bone mineral density due to estrogen ablation treatments administered along with the above medications. Cancer patients receive a larger dose of zolendronic acid at much more frequent administrations, than those receiving Reclast (zoledronic acid).

Osteoporosis patients who take oral or infused bisphosphonates are also at risk for osteonecrosis of the jaw, but at a somewhat lower incidence. [7]

Atypical Subtrochanteric Femoral Fractures occur in the thigh bone with little force. These fractures can happen with minimal to no trauma to those who've taken a bisphosphonate for several years that have caused the bone to accumulate micro-damage and mineralization. Symptoms of these fractures are prodromal pain (pain that occurs before the fracture), cortical bone thickening, slow-healing, and bilaterality with this type of drug exposure.

Pain in the thigh and groin are hallmarks of symptoms that present before the fracture. If you are experiencing this type of pain, and have taken these drugs report this symptom ASAP! The sooner you report the more the surgeon can do. [5]

Forteo is being used, another osteoporosis drug - which is a man-made parathyroid hormone - to help heal these types of fractures and surgeons are seeing great success with this type of treatment in speeding the rate of healing. Forteo also has an analgesic affect on the pain so its benefits are two-fold, and Forteo only needs to be used for a short period of time, with these types of fractures, and usually a few months at most.

We won't know the true numbers on the incidence of these fractures until the emergency rooms learn to code these fractures correctly. Unfortunately when patients with these types of fractures arrive at the E.R. most times the fracture is coded as a broken hip, due to osteoporosis, and not an atypical femoral fracture occurring from minimal traumas, which are two totally different types of injuries.

Esophageal cancers have been linked to the use of these bisphosphonates and the FDA recently released the following warning on this in July 2011. This report was based on two conflicting studies, so the FDA needs additional time to come to a conclusion on whether this is a confirmed risk for patients taking these medications. [6]

Intense Musculoskeletal Pain is another side effect the FDA has discussed with these bisphosphonates. [4]

Atrial Fibrillation has been associated with the use of Fosamax and all the bisphosphonates used to treat post-menopausal osteoporosis.

According to the FDA on October 01, 2007 "FDA reviewed spontaneous post marketing reports of atrial fibrillation reported in association with oral and intravenous bisphosphonates and did not identify a population of bisphosphonate users at increased risk of atrial fibrillation. In addition, as part of the data review for the recent approval of once-yearly Reclast for the treatment of postmenopausal osteoporosis, FDA evaluated the possible association between atrial fibrillation and the use of Reclast. Most cases of atrial fibrillation occurred more than a month after drug infusion." [3]

As a result of this long-term data collected on this particular bisphosphonate, Fosamax, and others, the FDA is conducting a Panel Advisory Meeting on September 9, 2011 from 8:30 a.m. to 4:30 p.m. in Silver Springs Maryland. Both patients who've sustained injuries as a result of these drugs are encouraged to speak, and also the public is welcome. It will take some time for the Panel Committee to come to some resolution on these drugs and we hope to know what that will be in the near future.   For more information from the FDA on this Drug Safety and Risk Management Advisory Committee follow the above link.

We truly hope that if you have taken any of these drugs that you haven't had any serious side effects, but if you have we hope you will get some closure with this FDA meeting.


1 Fosamax Prescribing Information: Merck & CO., INC. 2011

2 Medical Dictionary by Free Dictionary 2011

3 FDA on Atrial Fibrillation October 01, 2007

4 American Academy of Family Physicians on FDA warning of Severe Incapacitating Bone Pain from bisphosphonates January 9, 2008

5 FDA warning on Atypical Femoral Fractures with bisphosphonate use October 13, 2010

6 FDA warning on potential increased risk of Esophageal Cancer with bisphosphonate use

7 FDA warning on Osteonecrosis of the Jaw in patients treated with bisphosphonates December 2004,