Angular Cheilitis: A deficiency of B2, Riboflavin. Very common on a modern Western diet. Don’t be a vegetarian! Don’t drink any kind of soda, cola, fizzy pop drink.
Take 1 x B2 and 1x multi-B tablet for a week, then once a week thereafter.
Source: Experience, Merck’s manual, Upjohn’s vitamin manual, the vitamin bible. Newton’s pharmacy.