M Toronto Myositis Centreat St. Michael's Hospital
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Bisphosphonates

risedronate (Actonel), alendronate (Fosamax), zoledronic acid · say “bis-FOS-fo-nates”
Bone protection
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Take it correctly, and see your dentist.

Oral bisphosphonates must be taken on an empty stomach with a full glass of water, staying upright afterward. A dental check is done before starting.

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What it is

Protecting your bones from steroids.

Bisphosphonates slow the breakdown of bone. Because long-term prednisone weakens bone and raises fracture risk, a bisphosphonate is often prescribed to prevent and treat steroid-induced osteoporosis. Common options are risedronate (Actonel) and alendronate (Fosamax) taken by mouth, or zoledronic acid given once a year by infusion.

How to take it
  • Oral (risedronate, alendronate): taken weekly or monthly, first thing in the morning on an empty stomach, with a full glass of plain water.
  • After an oral dose, stay upright (sitting or standing) and take nothing else by mouth for at least 30 to 60 minutes, then eat.
  • Intravenous (zoledronic acid): given once a year by infusion, an option if tablets are not tolerated.
  • Keep your calcium and vitamin D adequate, since these medicines work best when they are.
What to expect
  • They lower fracture risk over months to years; you will not feel a day-to-day difference.
  • Your bone density is rechecked periodically to guide how long to continue.
  • A short flu-like reaction can follow the first IV dose and settles quickly.
Benefits

How it helps you.

Reduces fracture risk

Protects the spine and hip against the bone loss that long-term steroids cause.

Well established

Decades of evidence for preventing and treating osteoporosis.

Flexible options

Weekly or monthly tablets, or a once-yearly infusion.

Affordable

Available as low-cost generics.

Risks & side effects

What you should know.

Your doctor prescribed this because the expected benefits outweigh the risks for your situation. Here is the honest, full picture.

Common side effects
Heartburn or irritation
With tablets, especially if taken incorrectly. Correct technique prevents most of this.
Flu-like symptoms
After the first IV dose: aches, mild fever, tiredness for a day or two.
Muscle or joint aches
Occasionally, usually mild.
Serious but uncommon
Jaw osteonecrosis
Rare. Risk is lowered by a dental check before starting and good dental care. Tell your dentist you take it.
Atypical thigh fracture
Rare, with long-term use. Report new thigh or groin pain.
Esophageal irritation
With tablets taken incorrectly. Staying upright and taking with water prevents it.
Staying safe

Monitoring and precautions.

Regular monitoring
  • Calcium and vitamin D should be adequate before and during treatment.
  • A dental check is recommended before starting.
  • Bone density scans track how well it is working and how long to continue.
  • Kidney function is checked before an IV dose.
Daily precautions
  • Take tablets correctly: empty stomach, full glass of water, stay upright, nothing else by mouth for 30 to 60 minutes.
  • Keep up dental care and tell your dentist you take a bisphosphonate.
  • Maintain calcium and vitamin D.
  • Report new thigh or groin pain rather than waiting.
When to call your doctor

Contact the clinic if you notice:

New thigh or groin pain
A dull ache in the thigh or groin can rarely precede an atypical fracture. Report it.
Jaw pain or dental problems
Jaw pain, or a dental site that will not heal. Report promptly.
Severe heartburn or swallowing pain
With tablets, stop and call rather than pushing through.
Numbness or muscle cramps
May signal low calcium; report it.

Pregnancy & breastfeeding

Bisphosphonates are generally avoided in pregnancy and breastfeeding, since they stay in bone for a long time. Tell your doctor if you are pregnant or planning, so bone protection can be reviewed.

!

This guide is for education, not medical advice. Myositis treatment is individual, and many of these medications are used based on specialist experience and evidence rather than a formal Canadian myositis indication. Never start, stop, or change a medication without your own doctor. Your doses and choices are decided with your care team at the Centre.

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