Hi, I just got married and after getting married i had a massive acne breakout. I went to see the doctor and he put me on tetralysal 300 for 2 weeks. Today my tetralysal course has finished. I am supposed to have my periods since 5 days but nothing. I went for a pregnancy test which was negative. I am not having any pregnancy symptoms. I am generally very very regular with my periods. IS it possible that tetralysal might have caused the delay or missed period?