The aim of this form of treatment is to induce a local allergic skin reaction (contact dermatitis) that stimulates hair re-growth by distracting the immune system from attacking the hair follicles. Diphenylcyclopropenone (DPCP) is the most commonly used treatment in the UK.
This treatment is initially applied to a small area of the scalp or the arm, in a process called sensitisation – this makes the person allergic to the solution. Two weeks later a weaker concentration is then applied to the affected areas on the scalp. The solution usually remains on the skin for up to 24 hours and is then washed off. The aim of treatment is to trigger a mild reaction lasting 24-36 hours, with the scalp feeling a little itchy, red and flaky. The strength of the medication is gradually increased, depending on the level of the reaction.
The team at Salford NHS Foundation Trust have very kindly put together these helpful videos on: