I used it once a day throughout my cycle, and if I noticed shedding I used it twice a day till it subsided. Some people can do it twice with no problems- others will have trouble with a dry scalp. If you need to use it twice a day then get a healthy scalp conditioner, that will help with the dryness. There has to be a trade off here -- which would you rather have, a itchy flaky scalp for 8 weeks, or maybe some premature balding? I know what the answer is for me-
C