Capsaicin

Sounds like 'kap-SAY-i-sin'

Easy-to-read medicine information about capsaicin – what is it, how is it used and possible side effects.

Type of medicine Also called
  • Topical analgesic (which means a cream that is applied to the skin for pain relief) 
  • Zostrix®
  • Zostrix HP®

What is capsaicin?

  • Capsaicin is used to relieve certain types of pain such as pain caused by osteoarthritis or nerve pain caused by shingles or diabetes (diabetic peripheral neuropathy).
  • It works by decreasing a certain natural substance in your body called substance P, that helps pass pain signals to the brain. 
  • In New Zealand, capsaicin is available as a cream that is applied to the skin of the painful area. There are 2 strengths of capsaicin cream:
    • 0.025% (called Zostrix) which is used to relieve pain in osteoarthritis.
    • 0.075% (called Zostrix HP) which is used to relieve nerve pain caused by shingles or diabetes (diabetic peripheral neuropathy).  

How is capsaicin used?

  • Capsaicin cream is applied to the skin of the painful area.  
  • The usual dose of capsaicin cream is a pea-sized amount to the affected area 4 times daily (not more than every 4 hours).
  • Pain relief usually begins within the first week of treatment and increases with continuing regular application for the next 2 to 8 weeks.
  • Use this medication regularly to get the most benefit from it. To help you remember, use it at the same times each day.

Possible side effects

Like all medicines, capsaicin can cause unwanted side effects, although not everyone gets them. 

Side effects What should I do?
  • The most common side effect is a sensation of stinging or burning after application of capsaicin
  • This sensation is related to the action of capsaicin on the skin and is to be expected
  • This sensation usually eases after the first few days of application and in most cases will disappear with time and continued use
  • Blistering/swelling at the application site
  • Increased/unusual pain at the application site
  • Tell your doctor
  • Signs of an allergic reaction such as skin rash, itches, swelling of the face, lips, mouth and tongue or problems breathing
  • Tell your doctor immediately or ring HealthLine 0800 611 116

How to use capsaicin safely

  • Use a small amount of cream for each application and gently rub into the affected area.
  • Wash any left over cream from your hands after applying. If using the cream for arthritis in your hands, do not wash your hands for at least 30 minutes after applying the cream.  
  • Do not apply the cream to broken or irritated skin.
  • Avoid contact with eyes and mucous membranes
  • Do not apply bandages or heat (heating pads, hot water bottles, and heat lamps) to the area where the cream has been used.
  • Do not apply this medication immediately before or after activities such as bathing, swimming, sun bathing, or heavy exercise.
  • Avoid hot showers or baths immediately after application.

Learn more

The following links provide further information on capsaicin. Be aware that websites from other countries may contain information that differs from New Zealand recommendations.

Capsaicin Dermnet NZ
Zostrix Cream Medsafe Consumer Information Sheet, NZ
Zostrix HP Cream Medsafe Consumer Information Sheet, NZ