Q: My wife is 27 years old. She has dark brown patches on her forehead, below and above eyes and on her elbow. The biopsy report of my wife shows she has toxic melanosis. What is the cause and treatment for it?

A:Toxic melanosis is an umbrella term that encompasses a huge number of causes of inflammatory and non-inflammatory pigmentation. Examples include Riehls melanosis, pigmented cosmetic dermatitis, pigmented contact dermatitis, pigmented cosmetic contact dermatitis, melanosis faciei feminae, erythroderma exfoliativa recidivans faciei, lichen ruber planus cum pigmentatione. They are all brought on by a combination of sunlight, cosmetics, and internal medication. Proper history-taking gives the clues to aetiology. All of them respond to oral HCQS, topical steroids and topical hydroquinone, singly or in combination.