Introduction of Bisphosphonates to the Public
Bisphosphonates were introduced to the public in the 1990’s (Strewler, 2005).
The Indication for Bisphosphonates and Patient Population that Most Commonly Receives a Prescription for the Drug
Bisphosphonates are commonly used in the alleviation of osteoporosis in people of all ethnicities and gender. However, it is commonly used among women past the age of menopause, which is usually at the age of 50 years and above (National Osteoporosis Foundation, 2010. Since menopause is a universal phenomenon in all females, bisphosphonate prescriptions apply to women of all ethnicities. Bisphosphonates are also used in the treatment of breast malignancy that metastasizes to the bone (Body, 2003). Several studies have shown that its use over a period of about five years leads to a substantial reduction in the chances of having bone fractures.
Pharmacokinetics of Bisphosphonates
Bisphosphonates attach sturdily to hydroxyapatite and remains sedentary until the bone holding bisphosphonates are reabsorbed. The bisphosphonates then move locally and systemically and attach again to the exteriors of the bones (Cremers, Pillai, & Papapoulos, 2005). The half-life of the drug following assimilation into mineralized bone is ten years.
Pharmacodynamics of Bisphosphonates
Bisphosphonates have an elevated attraction for bone tissue and cling firmly to the surfaces of bones and obstruct the actions of the enzyme farnesyl pyrophosphate synthase that is vital to the formation of the cytoskeleton in osteoclasts. As a result, the process of bone resorption is constrained.
Bisphosphonate Dosage
The dosage of bisphosphonates depends on the type of drug. For example, alendronate is available in 10mg everyday tablets, 70mg weekly pill or fluid preparation, and a 70mg weekly pill for treatment (National Osteoporosis Foundation, 2010). Prevention formulations of the same drug are 5mg daily pills and 35mg weekly pills. Ibandronate, conversely, is available in 2.5mg everyday pills, 150mg once-a-month pills and 3mg quarterly intravenous injections.
Monitoring Required with the Medication
Before administering bisphosphonates, patients must be assessed to detect the presence of possibly treatable causes of other factors causing to osteoporosis. This assessment includes testing for calcium levels, vitamin D shortage, and renal damage by quantifying serum, creatinine and 25-hydroxyvitamin D. Any disorder should be corrected before treatment. A careful history to identify any aberrations of the esophagus and an incapability to stay upright for about an hour should also be performed. Impending plans for intrusive dental procedures should be discussed, and the prescription of bisphosphonates postponed until the jaw has healed sufficiently to avoid osteonecrosis of the jaw.
Common Side Effects of Bisphosphonates
The most prevalent side effect that comes from the use of bisphosphonates is the disturbance of the gastrointestinal tract. Bisphosphonates also lead to the irritation of the esophageal, which is likely to erode the esophagus and predispose the user to esophageal cancer. Bone cells in the jaw may also die in a process known as osteonecrosis, which mostly happens following dental surgery involving the jaw in patients who receive intravenous doses of bisphosphonates. Despite treating bones, bisphosphonates can lead to bone pain, muscle discomfort, and joint aches. As a result, the Food and Drug Administration (FDA) has published a caveat regarding this problem and encourages healthcare specialists to assess such discomfort in patients on bisphosphonates to decide whether or not to withdraw the drug. The use of bisphosphonates brings about aberrant heart rhythm, which is a condition that is known as atrial fibrillation, particularly in ageing women. The abnormal splintering of the femur has also been reported following extended usage of the drug for several years.
The Average Cost of Bisphosphonates
The average cost is determined by the type of drug and is approximately $775 a month for pamidronate therapy. Overall, bisphosphonates are approximated to cost about $3800 per woman, but save approximately $2,100 on costs related to fractures.
Clinical Practice Guideline or Professional Group Recommendation for the Use of Bisphosphonates
The National Osteoporosis Foundation (2010), which comprises a multi-specialty assembly of medical specialists in the area of bone health, has formulated guidelines to govern clinician’s use of bisphosphonates in the treatment of osteoporosis. The prescription of bisphosphonates is determined by the patient’s bone mineral density (BMD). The decision to initiate treatment using the drug should only be made if the patient has low bone mass with a T-score that ranges from 1 to 2.5 at the femoral neck and spine as well as a 10-year chance of hip fracture.
The Controversy that Surrounds the Use of Bisphosphonates
Even though bisphosphonates are mostly nontoxic and well endured, disquiets have arisen regarding the negative upshots associated with the longstanding use of the drug (Eriksen, 2012). In the majority of patients with osteoporosis and osteopenia, the advantages of the drug are more than its shortcomings. Additionally, the drug amasses in bone tissue leading to a reduction in the chances of developing fractures long after the treatment is terminated (Whitaker, Guo, Kehoe, & Benson, 2012). Therefore, it is necessary to deliberate a break from the drug (McClung, 2013). There is extensive controversy about the ideal length of treatment and the period of the break, which should be determined by the patients’ separate evaluation of dangers and benefits (Whitaker et al., 2012). The two main adverse effects associated with the longstanding use of bisphosphonates include osteonecrosis of the jaw as well as atypical femur fractures (Diab & Watts, 2013).
The controversy surrounding the use of bisphosphonates in osteoporosis is related to its side effects after protracted usage. Currently, there is insufficient proof to support the necessity of a drug break or to ascertain the efficacy of treatment following the resumption of therapy. Also, there is an absence of strong substantiation to act as a guide regarding the length of treatment or break and when to resume treatment. However, a study by Diab and Watts (2012) recommends that patients with diminished chances of having fractures should not be treated with bisphosphonates while those with moderate risk should only use the drugs for a maximum of ten years followed by a three to five-year break until there is a substantial decline in bone mass density.
Bisphosphonates Alternatives
The first alternative to bisphosphonates is denosumab (Prolia), which is an entirely fully human monoclonal antibody used in the management of postmenopausal women with elevated chances of osteoporotic fractures (MedlinePlus, 2015). The drug is administered as an injection once every six months. Its mode of action entails the containment of bone renewal that may increase the chances of osteonecrosis of the jaw. Reported side effects include limb and back aches, elevated cholesterol, and diseases of the urinary bladder.
Calcitonin-salmon (Miacalcin) is an artificial form of the body’s inherent hormone, calcitonin that is secreted by the thyroid gland (Drugs.com, 2015). It works by preventing the elimination of bone by osteoclasts and stimulates the formation of novel bone tissue by osteoblasts. The drug exists as a nasal spray and injection.
My Decision on the Use of Bisphosphonates
For the majority of patients suffering from osteoporosis, the advantages of therapy using bisphosphonates overshadow the risks. Therefore, I would still prescribe the drug in the management of osteoporosis. However, given the few cases of adverse effects associated with the drug, I would exercise caution when prescribing the drug and only recommend it for short-term usage. Alternatively, I would keep an eye on the patient’s reaction to the drug and prescribe alternative drugs if the patient’s reaction to bisphosphonates is not satisfactory.
References
Body, J-J. (2003). Effectiveness and cost of bisphosphonate therapy in tumor bone disease. Cancer, 97(3 Suppl), 859 – 865.
Cremers, C. L. M. S., Pillai, G. & Papapoulos, S. E. (2005). Pharmacokinetics/ pharmacodynamics of bisphosphonates use for optimization of intermittent therapy for osteoporosis. Clinical pharmacokinetics, 44(6), 551-570.
Diab D., Watts N. (2012). Bisphosphonates in the treatment of osteoporosis. Endocrinology and Metabolism Clinics of North America, 41(3), 487–506.
Diab, B. & Watts, N. (2013). Bisphosphonate drug holiday: who, when and how long. Therapeutic Advances in Musculoskeletal Disease, 5(3), 107-111.
Drugs.com. (2015). Miacalcin (calcitonin) uses, dosage, side effects. Web.
Eriksen, E. F. (2012). Treatment of osteopenia. Reviews in Endocrine and Metabolic Disorders, 13(3), 209–223.
McClung, M. (2013). Controversies in osteoporosis management: concerns about bisphosphonates and when are “drug holidays” required? Clinical Obstetrics & Gynecology, 56(4), 743-748.
MedlinePlus. (2015). Denosumab injection. Web.
National Osteoporosis Foundation. (2010). Clinician’s guide to prevention and treatment of osteoporosis. Washington, DC: National Osteoporosis Foundation. Web.
Strewler, G. J. (2005). Long-term bisphosphonates for osteoporosis: An introduction. BoneKEy-Osteovision, 2(2005), 6–9.
Whitaker M., Guo J., Kehoe T., Benson G. (2012). Bisphosphonates for osteoporosis–where do we go from here? New England Journal of Medicine, 366(22), 2048–2051.