A recently released Canadian research study confirms what has been shown in past preliminary studies; – inflammation of the eye as a possible side effect of bisphosphonate therapy is very rare. Bisphosphonates include Alendronate (Fosamax), Risedronate (Actonel), Etidronate (Didrocal) and Zoledronic Acid (Aclasta).

In this new study to evaluate the risk of inflammation of the eye while taking bisphosphonates, Dr Etminan and his colleagues reviewed the electronic medical records for specific diagnoses and medications in all British Columbia residents seen by an eye doctor from 2000 to 2007. They found that uveitis (inflammation of the uvea or middle layer of the eye) occurred in 0.29% of people using bisphosphonates for the first time. Uveitis also occurred in 0.20% of people not taking bisphosphonates. Uveitis can cause blurred vision, eye pain and redness. The researchers also found that episcleritis (inflammation of the sclera or white part of the eye) occurred in 0.63% of bisphosphonates users and in 0.36% of non-users. Episcleritis can cause eye pain, redness, tearing and light sensitivity.

To be clear, this study does not prove that bisphosphonates cause these types of eye problems. In addition, these eye conditions are quite rare and the number of people that are affected is very small. The overall risk of eye inflammation in people taking bisphosphonates is very low compared to the much larger risk of a fracture (broken bone) in people with osteoporosis who do not take bisphosphonates.

If you are taking a bisphosphonate and do not have any eye symptoms continue to take your bisphosphonate as you normally would. However, if you are taking a bisphosphonate and you do develop any symptoms of eye inflammation report these to your doctor as soon as possible. Your doctor will make sure that you get the proper treatment for your eyes and will advise you whether to continue with bisphosphonate therapy or to switch to a different type of therapy for your Osteoporosis.