Sexually active male comes with complaints of recurrent ulcers over the glans which heals with hyperpigmentation, probable diagnosis is -
Fixed drug eruption manifests as skin lesions at fixed sites following drug intake. The lesions progressively fade over several days often leaving a residual post inflammatory brown pigmentation. Page no.294. Reference IADVL's concise textbook of dermatology
Aphathous ulcer
Fixed drug eruption
Herpes genitalis
Chlamydial infection
Autoimmune skin disorders