Pamidronate is the generic name; the brand name is Aredia. It is in the "bisphosphonate" category, similar to alendronate (Fosamax) and risedronate (Actonel). These medicines were designed to make bones stronger and they do not occur in nature. They work by stopping the bone from dissolving. They attach firmly to the bone and remain in the bone for many years.
The Federal Drug Administration has approved pamidronate to treat bone cancer or Paget's disease. Other conditions which have been studied but do not have official approval include fibrous dysplasia, osteoporosis after organ transplantation, and bone diseases with high bone resorption rates.
Pamidronate is given only as an intravenous infusion. The dose is between 30 and 90 mg per infusion, which lasts for 2 hours. You do not have to be fasting. In patients with high blood calcium due to cancer, the infusions are given once a month. For Paget's disease and fibrous dysplasia, the frequency of infusions must be determined on an individual basis. For osteoporosis, the infusions are given every six months at lower doses. We do not know how long this medication should be given when it is used to treat osteoporosis, but currently in organ transplant patients I recommend up to 2 years ( 1 to 4 doses).
The day after the infusion it is common to have a fever. Some patients feel like they are getting the flu and feel aching and tired. This usually lasts only one or two days. You may have pain in the bone, especially if you have Paget's disease or fibrous dysplasia. Other complications are not common, and include a transient decrease in the white blood cell count or blood calcium. The infusion site may become sore or infected. Rare side effects are inflammation of the eyes, kidney damage, or problems with the bones underneath the teeth.
To be safe, the following blood tests should be normal before giving pamidronate: calcium (greater than 9.0 mg/dl) creatinine, white blood cell count, vitamin D (at least 20 ng/ml). It should not be given during an active infection.
You do not need other osteoporosis medications for at least 6 months after an infusion. You should be sure to get adequate calcium and vitamin D after pamidronate infusions.