From what I've observed, those who take a break or stop Minoxidil usually start to lose the results from the medication at around the three week mark.
Unfortunately yes, it's possible that taking a one week break from Minoxidil can actually lead to shedding. There is a member here by the username of zzzzz who had to stop using Minoxidil for a week and a half. Then a couple months later, they went through a massive and lost a lot of hair.
Last year in the Summer of 2014, I quit using Minoxidil for two months and I went through a massive shed and lost a lot of density, and ever since then, my hair hasn't been the same. That was almost one year ago and my hair is taking very long to recover.
The only thing that I can recommend is to keep using Minoxidil to keep hair growth and prevent shedding.
