Bisphosphanates

Last updated 12.12.13

Definition

- Medication used to reduce bone absorption

Features

- Inhibits resorption of bone by inhibiting osteoclasts

- BMD repeated 1-2yrs after commencement if for Osteoporosis

Indications

- Prevention & treatment of Osteoporosis

- Increase bone denisty by 4-8% in spine & 1-3% in hip over 3-4yrs

- Reduce spinal fractures by 30-70% & hip fractures by 30-50%

- Pagets disease of bone (Osteitis Deformans)

- Advanced Breast Ca

- Multiple Myeloma

- Hypercalcaemia

PBS Indications

- Listing depends on particular medication

- Osteoporosis with minimal trauma fracture, 70+ yrs old with BMD T-score <-3.0

- Corticosteroids: 7.5mg+ daily for 3months+ & BMD <-1.5

- Pagets disease of the bone

Side Effects

- Osteonecrosis of jaw

- Rare but serious

- Higher risk if: IV Bisphosphanate, pre-existing poor dental hygeine & dental procedures whilst on Bisphosphanates

- Consider dental referral prior to commencing

- Oesophageal irritation/oesophagitis, Gastritis

- Avoid combination with NSAIDs

- Headaches, dizziness

- Mouth ulcers

- Myalgia, arthralgia

- Iritis

Drugs

- Alendronate +/- Calcium +/- Vitamin D

- Etidronate +/- Calcium

- Pamidronate

- Ibandronate

- Risedronate +/- Calcium

- Clodronate

- Tiludronate

- Zolendronate

Administration

- Should correct Vitamin D levels prior to commencement

- Take on an empty stomach with a glass of water

- Best taken first thing in the morning

- Taken at least 30min before or after other medication

- Cannot lie down for at leas 30 minutes after taking (to reduce oesophageal irritation)

- Often prescribed with calcium & vitamin D

- For osteoporosis usually taken for 5yrs+

- Absorption may be reduced by antacids & PPIs

References

 TGA: Bisphosphanate drugs and Osteonecrosis of the Jaw 2007

Australian Rheumatology Association: Patient Information on Bisphosphanates