How long until the lotrimin (clotrimazole) af medicine starts working on your tinea?

2 weeks: I think 2 weeks of applying the medication would be a fair time frame. Keep in mind not all medication works on all coonditions and sometimes you may have to switch to a different medication. On the feet, you can try applying a mositurizer first as the skin on the bottom of the foot is thicker and tis will soften to allow better penetration of the antifungal.