Various drugs are used to treat and manage osteoporosis.

BISPHOSPHONATES reduce the activity of cells that cause bone loss with little or no effect on cells that build up bone. They are effective in preventing and treating osteoporosis. They are taken on an empty stomach with plain water only daily or once a week. One should not take mineral water, coffee, tea, juice or dairy products before taking the tablet, which should be swallowed and not chewed or sucked.

If there is chest pain, heartburn, difficult or painful swallowing, one should stop taking the tablet and consult the doctor. Other side effects include abdominal discomfort, nausea, vomiting, diarrhoea, constipation, gas, headache and muscle, bone, or joint aches.

Bisphosphonates are not suitable for those who have problems in the oesophagus, kidneys that are not functioning well, low or high levels of blood calcium, cannot stay in an upright position for at least 30 minutes or are allergic to it.

·Risedronate is used to prevent and treat osteoporosis in women after menopause as well as women and men who are starting or continuing steroids for chronic medical conditions. It increases bone density and reduces the risk of spinal and non-spinal fractures. It helps preserve bone micro-architecture, provides sustained spinal fracture reduction over five years and reduces non-spinal fractures significantly over three years.

·Alendronate is used to prevent or treat osteoporosis in women after menopause, increase bone mass in men with osteoporosis and to treat women and men who are taking steroids. It increases bone density in both the spine and hip. There are reports that a combination of alendronate and oestrogen is more effective than either taken separately. Side effects are generally mild.

·Ibandronate is used to treat and prevent osteoporosis in women after menopause. It increases bone density in the spine and hip, and reduces the risk of spine fractures. It is available in a daily, monthly or three monthly dose. Side effects are generally mild.

·Etidronate is a bisphosphonate used to treat and prevent osteoporosis in women after menopause. It increases bone density at the lumbar spine and hip, and reduces the incidence risk of spine and hip fractures. The dose is daily for two weeks every three months. Continuous daily use will result in demineralisation.

Selective Oestrogen Receptor Modulators (SERMs)

These compounds bind to oestrogen receptors and bring about an oestrogen-like (agonist) effect in some tissues and an oestrogen-blocking (antagonist) effect in other tissues. There are two main types of oestrogen receptors. Each SERM binds the receptor in a unique configuration and depending on the tissue which the SERM binds to the receptor, it either blocks or activates its function. SERMs have no beneficial effect on menopausal symptoms while its effects on brain function are not yet known.

They are only prescribed after menopause and to those with few or no menopausal symptoms. It is unknown whether a combination of hormone and a SERM provides any advantage or loss of an individual effect, and their combined use is not recommended.

Raloxifene is a second generation SERM that mimics the oestrogen effects on bones but does not have oestrogen’s effects on the breast or uterus. It prevents bone loss, has beneficial effects on bone mass and reduces the risk of spine fractures. It is most suitable for osteopenic or osteoporotic women, who have breast or uterine problems, concerns about hormones or no major menopausal symptoms. It is taken once daily. It has a small increased risk of thromboembolism (VTE) similar to oral oestrogen. However, no cases of VTE have been reported in postmenopausal Asian women on raloxifene.

Calcitonin

This hormone is involved in calcium regulation and bone metabolism. It is taken as a single daily nasal spray or as an injection under the skin. In women who are at least five years postmenopausal, it slows bone loss and increases spinal bone density. Some patients also report pain relief from bone fractures. Injected calcitonin may cause an allergic reaction, flushing of the face and hands, nausea, increased urinary frequency and skin rash. The side effects are a runny nose and other signs of nasal irritation.

Strontium Ranelate

This compound has a novel action as it increases bone formation and at the same time reduces bone loss. It is used for treating postmenopausal osteoporosis and reduces the risk of spinal and non-spinal fractures. In addition, strontium ranelate has demonstrated reduction in fracture risk in a wide range of patients, from those with mild osteoporosis (osteopenia) to those above 80 years, regardless of severity of the condition. It is taken daily with a glass of water. The common side effects are nausea and diarrhoea.

Parathyroid hormone

Parathyroid hormone and its analogue teriparatide, which is a recombinant human parathyroid hormone, increases bone turnover, stimulating bone formation to a greater extent than bone loss. It increases bone density in the spine and hip and reduces the risk of spinal fractures significantly. It is used to treat individuals with severe osteoporosis especially after a fracture. Most doctors stop the bisphosphonates before starting teriparatide. It is given as a subcutaneous injection daily. The common side effects include pain in a limb, anaemia, depression, vertigo, nausea, dizziness and muscle cramps. It cannot be given to those who have prior radiation to the skeleton, bone cancers and metabolic bone conditions other than osteoporosis.

Managing osteoporotic fractures

Surgery is used early in most instances today as conservative treatment results in myriad problems such as respiratory problems, thromboembolism, pressure ulcers, additional bone loss.

The majority of osteoporotic spinal fractures are stable. Operative treatment is carried out if there is spinal cord or nerve root compression. It may be used in chronic backache and progressive spinal deformities. Supportive braces may be used temporarily.

The relief of spinal pain can be problematic. Narcotic analgesics may be needed. Calcitonin is useful in providing pain relief. Physiotherapy and a brace can provide significant pain relief. Healing can be aided by adequate intakes of calcium, vitamin D and protein. Parathyroid hormone is prescribed in severe osteoporosis especially after a fracture.

Source: Dr Milton Lum