My doctor always gives me one Rx and tells me I can only take it for 1 week than 3 weeks off and then another week. In 1 week my nail infection almost clears up but then I have to stop taking it for no reason she has given me and wait 3 weeks until I can take another week. In 2 weeks my infection is horrible again. Can I just take this Rx until the infection is gone? Is there any reason I can't take it foe more than a week?