M Toronto Myositis Centreat St. Michael's Hospital
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Calcium channel blockers

nifedipine (Adalat), amlodipine (Norvasc) · say “nif-ED-i-peen, am-LO-di-peen”
For Raynaud's (usual first choice)
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The usual first medicine for Raynaud's.

These relax blood vessels so more blood reaches your fingers and toes. Your doctor starts at a low dose and builds up slowly to limit side effects.

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What it is

Opening the blood vessels in your fingers.

Raynaud's is when cold or stress makes the small blood vessels in your fingers and toes tighten, so they turn white, then blue, then red, and can hurt. In some people this leads to sore spots on the fingertips that are slow to heal, called finger ulcers. Calcium channel blockers relax these blood vessels and are the usual first medicine. They are used this way based on long experience.

How to take it
  • A tablet once or twice a day, usually the long-acting form.
  • Your doctor starts low and increases the dose slowly.
  • Take it at the same time each day.
  • If you also take it for blood pressure, do not stop suddenly. Check with your doctor.
What to expect
  • Fewer and milder attacks over a few weeks.
  • It helps protect your fingers from ulcers more than it heals ulcers you already have.
  • The dose is adjusted to balance the benefit against side effects like headache or ankle swelling.
Benefits

How it helps you.

Fewer, milder attacks

Reduces how often Raynaud's happens and how bad it is.

A simple daily pill

Easy to take, and widely used.

Protects your fingers

Helps prevent painful finger ulcers.

Well established

A long track record and low cost.

Also lowers blood pressure

A helpful bonus if your blood pressure runs high.

Risks & side effects

What you should know.

Your doctor chose this because the likely benefits outweigh the risks for you. Here is the honest, full picture.

Common side effects
Headache
Common early on, and often eases with time.
Flushing
A warm, red face for a while after a dose.
Ankle swelling
Puffy ankles can occur. Tell your doctor if it bothers you.
Dizziness
Feeling lightheaded, especially when standing up quickly.
Serious but uncommon
Low blood pressure
Rarely, blood pressure can drop too far, causing faintness. The dose can be adjusted.
Bothersome swelling
Ankle swelling that affects you can usually be improved by changing the dose or medicine.
Staying safe

Monitoring and precautions.

Regular monitoring
  • Blood pressure is checked, especially as the dose goes up.
  • How your fingers and toes are doing is reviewed at visits.
  • Any ankle swelling is noted and managed.
Everyday precautions
  • Keep warm. Layers, gloves, and hand warmers help a lot, and reduce how much medicine you need.
  • Stop smoking. Nicotine tightens blood vessels and works against the medicine.
  • Limit caffeine and avoid decongestants (cold medicines that narrow vessels).
  • Stand up slowly to avoid dizziness.
When to call your doctor

Contact the clinic if you notice:

A finger that stays white or blue
A fingertip that stays pale or blue, is very painful, or is cold and numb for a long time. Report it soon.
A sore that will not heal
A new sore or ulcer on a fingertip, or one that looks red, swollen, or infected.
Fainting or severe dizziness
Report this, as the dose may need changing.
Bad ankle swelling
Swelling that bothers you or does not settle.

Pregnancy & breastfeeding

Nifedipine is often the preferred Raynaud's medicine in pregnancy. Tell your doctor if you are pregnant or planning, so the right choice can be made.

!

This guide is for learning, not medical advice. Myositis care is different for everyone, and many of these medicines are used based on specialist experience rather than a formal Canadian myositis approval. Never start, stop, or change a medicine without your own doctor. Your doses are decided with your care team at the Centre.

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