回复：用过两个月，开始脸干，痛。后来不知为什么脸色发暗就停了

should start with lowest %, and use only at night, and use a lot of sunscreen in daytime. But, don't quit retin-a, it's a great thing for your skin. And better consult with dermatologiest to choose a suitable % for yourself. Or you could check out Green Cream or Neutrogena anti-wrinkle first, once your skin is adapted to retinol. You could move onto higher level %.