Capsi

Indications

Capsaicin is the substance that makes chilli peppers hot. Applied to the skin as a cream, gel or patch, it is used to relieve muscle and joint pain such as osteoarthritis pain, backache, sprains and strains, and certain types of nerve pain, for example pain that remains after shingles (post-herpetic neuralgia) and painful diabetic nerve damage.

How It Works

Capsaicin activates a pain receptor (TRPV1) on nerve endings in the skin, which first causes a warm or burning feeling. With regular use, these nerve endings become less sensitive and release less of the chemical (substance P) that carries pain signals, so pain is gradually reduced. Full benefit often takes 1 to 2 weeks of regular use.

Dosage and Administration

Creams and gels: adults apply a thin layer to the painful area 3 to 4 times a day, rubbing in well, or as directed on the label. Wash hands thoroughly with soap after use (unless the hands are being treated). Do not use heating pads or tight bandages over the area. High-strength patches are applied only by a health professional in a clinic.

Interactions

No important interactions with oral medicines are known. Avoid using other skin rubs, heat products or creams on the same area at the same time. ACE inhibitors such as Enalapril may rarely increase the chance of cough.

Contraindications

Do not use if you are allergic to capsaicin or chilli peppers, or on broken, irritated or infected skin, open wounds, or near the eyes and mucous membranes.

Side Effects

A burning, stinging or warm feeling and redness where it is applied are common, especially in the first days, and usually lessen with continued use. Coughing or sneezing may occur if dried cream is breathed in.

Get urgent medical help if the burning becomes severe or blisters form, if it gets into the eyes and pain does not settle after rinsing, or if you have signs of a serious allergic reaction such as swelling of the face or difficulty breathing.

Pregnancy and Lactation

Little capsaicin is absorbed through the skin, but safety in pregnancy and breastfeeding is not well studied. Use only on medical advice, and do not apply to the breast area while breastfeeding.

Precautions and Warnings

For external use only. Keep away from the eyes, nose, mouth and genitals, and do not touch them after applying. Avoid hot showers, sunbathing or strenuous exercise just before or after use, as heat increases burning. Stop and see a doctor if pain worsens or does not improve after 2 to 4 weeks. Not for children under 12 unless advised.

Overdose

Using too much on the skin causes more intense burning; wash with soap and cool water. If swallowed, it can cause burning in the mouth and stomach upset; seek medical advice, especially for a child.

Therapeutic Class

Topical analgesic (counter-irritant, TRPV1 agonist).

Storage

Store below 30°C in a dry place, away from light and out of the reach of children.