Most itchy armpits are due to frequent sweating and sweat impregnation in the armpit area, which may be secondary to fungal or bacterial infections. The fungal or bacterial infection will produce certain fermentation and release irritants, including ammonia and other inflammatory factors, which cause localized itching of the skin. Therefore, itching usually requires topical cleansing, which is followed by oral anti-itch medications, such as antihistamines, and usually oral loratadine or levocetirizine hydrochloride.