Shingles is an outbreak of rash or blisters on the skin that is caused by the same virus that causes chickenpox – the varicella-zoster virus. Anyone who once had chickenpox is at risk of shingles because the virus can become reactivated years after the initial infection. Post-herpetic neuralgia (PHN) is a condition that affects nerve fibres and the skin that can cause excruciating pain for weeks, months or even years. Approximately 10 to 15 per cent of patients who have shingles experience PHN, and the complication is even more common in elderly patients.

Qutenza contains capsaicin, a compound found in chili peppers. Although there are over-the-counter products with lower concentrations of capsaicin that are marketed for the treatment of PHN, Qutenza is the first pure, concentrated, synthetic capsaicin-containing prescription drug to undergo FDA review. It was approved on 16 November.

‘This new product can provide effective pain relief for patients who suffer from PHN,’ said Bob Rappaport, MD, director of the Division of Anesthesia, Analgesia and Rheumatology Products in the FDA’s Center for Drug Evaluation and Research.

The most frequently reported adverse drug reactions included pain, swelling, itching, redness, and bumps at the application site.

Qutenza must be applied to the skin by a health care professional because placement of the patch can be painful, requiring use of a local topical anaesthetic, as well as additional pain relief such as ice or the use of opioid pain relievers. The patient must also be monitored for at least one hour because there is a risk of a substantial rise in blood pressure after patch placement.