Alendronic Acid Weekly

How it works

Like daily alendronate it binds bone mineral and inhibits osteoclast farnesyl pyrophosphate synthase, suppressing bone resorption; the larger weekly dose maintains the same antiresorptive effect.

Prescribing in practice

• The same strict administration rules apply on the chosen weekly dosing day: take on rising with plain water and remain upright without food or other medicines until after the post-dose interval, as oesophageal injury risk is the key hazard.
• If a weekly dose is missed it should be taken the next morning and the patient should then return to the original chosen day, not double up.
• Ensure calcium and vitamin D sufficiency and counsel on the rare risks of osteonecrosis of the jaw and atypical femoral fracture.

Monitoring

Monitor renal function and calcium, and periodically reassess fracture risk and the case for a treatment break after extended use.

Counselling the patient

• Take it on the same chosen day each week, first thing with plain water, then stay upright and avoid food and other tablets until after the interval.
• If you forget, take it the next morning and then go back to your usual day.
• Report swallowing problems, heartburn or new thigh or groin pain, and keep up good dental care.

Evidence & guidelines

Weekly dosing was shown to be therapeutically equivalent to daily alendronate on bone density and is endorsed within NICE osteoporosis guidance.