Bisphosphonates Flashcards
1
Q
What are examples of generic and brand names of bisphosphonates?
A
- Alendronic acid (Fosamax)
- Risedronate (Actonel)
- Pamidronate
- Zoledronic acid
2
Q
What is the method of action of bisphosphonates?
A
- Similar structure to naturally occurring pyrophosphate – readily incorporated into the bone
- Inhibit the action of osteoclasts which are cells responsible for bone resorption
- Also promotes apoptosis of the osteoclasts
- = ↓ in bone loss and improvement in bone mass
3
Q
What are the indications for bisphosphonates?
A
- Osteoporotic fragility fractures – Alendronic acid is 1st line
- Severe hypercalcaemia of malignancy – Pamidronate and zoledronic acid are used
- For patients with myeloma and breast cancer with bone metastases, bisphosphonates reduce the risk of pathological fractures, cord compression and need for radiotherapy/surgery
- Metabolically active Paget’s disease – reduces bone turnover and pain
4
Q
What are the contraindications for bisphosphonates?
A
- Severe renal impairment
- Hypocalcaemia
- Active upper GI disorder – oral administration contraindicated
- Smokers – due to risk of osteonecrosis
- Dental disease – due to risk of osteonecrosis
5
Q
What are the side effects of bisphosphonates?
A
- Oesophagitis
- Hypophosphataemia
- Osteonecrosis of the jaw – rare but serious, more likely with IV
- Atypical femoral fracture – rare but serious, more common on long term treatment
6
Q
What are the interactions with bisphosphonates?
A
- Calcium salt containing products e.g. antacids – due to binding to Ca so absorption is ↓
- Iron salts
7
Q
What organ eliminates bisphosphonates?
A
Kidney
8
Q
What information should be given to patients taking bisphosphonates?
A
- Should be swallowed whole at least 30 mins before breakfast/other medication
- Take with plenty of water
- Remain upright for 30 mins after taking to reduce oesophageal irritation
