Hyperpigmentation. Other than my face.

My hyperpigmentation keeps getting worse after using OTC medicines. Have used Tretin-A for some months. As soon as i stop, my face becomes very dark especially around my mouth. It looks as if i have a moustache and have shaved it. Its quite embarassing as people have told me that i look like a monkey. Doctor gave kojivit for lightening of darkness but i got allergy all over my face. Second time, i was prescribed Melaglow which also contained little bit of Kojivit and i got allergy again. So i discontinued medicines all together. Just using sun screen lotion and home made recipes to lighten the darkness. Sometimes, i feel that doctors have done a test and trail method for my condition. I am telling this because, i have used multiple medicines from multiple doctors which only aggravated my condition. Now, literally i am scared to consult a doctor and start medication again. I dont have any other medical complaints other than my face.