Alendronic acid Flashcards
What class of drug is alendronic acid?
Bisphosphonate
Name 3 other bisphosphonates.
Clodronate
Pamidronate
Risedronate
What is the mechanism of action of bisphosphonates?
Bisphosphonates are absorbed onto the hydroxyapatite crystals of bone
Bisphosphonate is released when osteoclasts resorb bone
The bisphosphonate interferes with the osteoclasts ability to continue to resorb bone
Also promotes apoptosis of osteoclasts and inhibits apoptosis of osteoblasts
What are the indications for alendronic acid?
Prophylaxis and treatment of osteoporosis
Hypercalcaemia of malignancy
Paget’s disease of bone
Osteolytic lesions and bony metastases
What are the common side effects of alendronic acid?
GI disturbance
Alopecia
Dizziness
Headache
MSK pain
Oesophagitis
What are the important side effects of alendronic acid?
Osteonecrosis of the jaw
Severe oesophagitis with stricture formation
Atypical stress fractures with long term use
What are the contraindications of alendronic acid?
Renal impairment
Pregnancy
Hypocalcaemia
Oesophageal abnormalities
What are the interactions of alendronic acid?
Antacids - reduced bisphosphonate absorption
Aminoglycoside antibiotics - increased risk of hypocalcaemia
Oral iron - reduced bisphosphonate action
How should alendronic acid be taken?
On an empty stomach (30 minutes before food)
With a full glass of water
Patient should remain sitting upright or standing for 30 minutes
What extra advice should patients taking alendronic acid be given?
To seek medical attention if they notice any symptoms of oesophageal dysfunction (difficulty swallowing, reflux)
Maintain good oral hygeine and see dentist regularly to prevent osteonecrosis of the jaw
What are the monitoring requirements for alendronic acid?
Monitor serum calcium during treatment
