Q: I have recently noticed skin discolouration in the armpits. The skin has become reddish brownish in colour but is neither itchy nor flaky. There is just a reddish brown patch under both the armpits. What could be the reason for that and should I apply any lotion or cream?

A:This could either be a fungal infection or erythrasma, which is a bacterial infection. A skin scraping (KOH exam for fungus) or woods lamp exam (for bacterial infection) would be diagnostic. Treatment for fungal infection is topical Oxyconazole or oral Fluconazole and for the bacterial infection is oral Roxithromycin.