###Human: I have acne marks due to pimples during periods. What has to be done? ###Assistant: Hi. I have gone through your case. First, you need to understand acne is common and you may experience frequent exacerbation due to stress or periods as you already told. Moreover, steroids should never be used in acne skin. In fact, this aggravates acne. Please apply Clindamycin gel two times a day on pimples. Apply Vitamin C serum on dark lesion for three months twice daily. Use Cetaphil cleanser.