Bone loss medications such as bisphosphonates may be used to treat complex regional pain syndrome (CRPS). Bisphosphonates are effective for bone loss, making them common treatments for bone conditions such as osteoporosis. In CRPS, bisphosphonates help manage pain and bone loss that may occur in the affected region. CRPS can be complex to diagnose and treat. For this reason, bone loss medications may not be the only type of treatment recommended for CRPS patients.
How Bisphosphonates Work
Bone loss medications can prevent and manage bone loss by reducing a process called bone resorption. Bone resorption is a natural process in which bone is broken down. During this process, minerals are released and calcium is absorbed into the blood from the bone fluid. Typically, new bone tissue replaces the broken down tissue to maintain homeostasis, or balance.
In conditions such as CRPS and osteoporosis, bone resorption occurs faster or more frequently than new bone tissue develops. This leads to bone loss. Bone loss medications such as bisphosphonates encourage the death of osteoclasts, the cells responsible for bone resorption and breakdown. As a result, the bone loss process becomes slower.
Other Bisphosphonate Uses
Bone loss medications may be used for other conditions, such as:
- Paget’s disease of bone, which causes misshapen and enlarged bones
- Bone metastasis, or the invasion of cancer into bone tissue
- Multiple myeloma, a type of blood plasma cancer present in bone marrow
- Osteogenesis imperfecta, a congenital disorder causing chronic brittle bones
- Fibrous dysplasia, during which normal bone tissue is replaced with fibrous tissue resulting in bone expansion
- Primary hyperparathyroidism, a condition where excessive hormones cause increased blood calcium levels
Types of Bisphosphonates
There are several types of bisphosphonate drugs that are used to treat CRPS, osteoporosis, and other bone conditions. Examples of common drug names and their active ingredients include Fosamax (alendronate), Boniva (ibandronate), Actonel and Atelvia (risendronate), and Reclast (zoledronic acid). The majority of these drugs are taken orally. Reclast and other zoledronic acid bisphosphonates are administered intravenously (IV), or through the veins.
Bisphosphonates primarily benefit CRPS patients with patchy bone loss, or bone loss in certain areas affected by the condition. CRPS bone loss more commonly occurs during the later stages of the condition. Atrophy, or wasting away, may occur due to lack of use of the CRPS-affected region. CRPS-affected regions typically include a limb such as a hand, arm, foot, or leg.
CRPS patients who experience bone loss often experience severe pain as a result. Several studies support the theory that bisphosphonates may also provide pain relief for patients with CRPS and other conditions. However, there is not sufficient evidence to support the use of bisphosphonates specifically for pain relief. It is unadvised for patients to begin a bisphosphonate treatment regimen for pain as opposed to bone loss.
Bisphosphonate Side Effects
CRPS patients who are considering a bisphosphonate treatment regimen should be sure that they are fully educated on the possible side effects. Common side effects include upset stomach, as well as inflammation and erosion of the patient’s esophagus. For this reason, patients should remain upright for up to an hour after taking bisphosphonates orally.
While bisphosphonates can reduce pain in patients, they are also known to cause pain. Many patients have reported severe joint, bone, or musculoskeletal pain while taking bisphosphonates. For this reason, the U.S. Food and Drug Administration mandated label changes for bisphosphonate drugs.
Intravenous Side Effects
When administered intravenously, or directly into veins, patients may experience flu-like symptoms and fever after the first treatment infusion. This is believed to be caused by the activation of a specific type of cells. In most cases, these symptoms do not persist after the first treatment. Intravenous bisphosphonates are also associated with a severe condition called osteonecrosis of the jaw (ONJ). Osteonecrosis of the jaw may lead to deterioration of and breakdown of the jaw bone.
Ruggiero, Salvatore L. “Bisphosphonate-Related Osteonecrosis of the Jaw: An Overview.” Annals of the New York Academy of Sciences 1218.1 (2011): 38-46. Academic Search Complete. Web. 13 Mar. 2014.
Scott, Mollie Ashe, Lindsy Meadowcraft, and Debbie Skolnik. “FPIN’s Clinical Inquiries. Risks of Bisphosphonate Use.” American Family Physician 88.10 (2013): 697. MEDLINE with Full Text. Web. 10 Mar. 2014.
Silverman, Stuart L. “Bisphosphonate Use in Conditions other than Osteoporosis.” Annals of the New York Academy of Sciences 1218.1 (2011): 33-37. Academic Search Complete. Web. 10 Mar. 2014.