Zoledronic Acid (Rheumatology — Osteoporosis)

How it works

It inhibits osteoclast-mediated bone resorption by interfering with the mevalonate pathway, increasing bone mineral density.

Prescribing in practice

• Correct hypocalcaemia and ensure adequate vitamin D and calcium before infusion, as the infusion can precipitate dangerous hypocalcaemia, and it is contraindicated in significant renal impairment.
• Ensure good hydration and assess renal function before each dose, since rapid or repeated infusion can cause acute kidney injury.
• Counsel on the rare risks of osteonecrosis of the jaw and atypical femoral fractures, and arrange a dental check before treatment where needed.

Monitoring

Monitor renal function and serum calcium before infusion, and review for acute-phase reactions, jaw symptoms, and atypical thigh or groin pain over time.

Counselling the patient

• A flu-like reaction with fever and aches is common after the first infusion and usually settles within a few days.
• Maintain good calcium and vitamin D intake and attend dental check-ups.
• Report any new thigh, hip, or groin pain, or jaw pain, to your doctor.

Evidence & guidelines

Annual zoledronic acid infusion reduces vertebral and non-vertebral fractures in osteoporosis trials and is recommended in NICE guidance.