Optimizing testosterone starts to work within days. There are several different ways to deliver testosterone which include cream, injection, pellet, and dissolvable lozenge. Depending on which type of delivery system being used will determine the rate of testosterone optimization. Within one week, you can expect a noticeable change in how you feel which should continue as your hormones start to get balanced. Generally speaking, every person is different and as such, HRT can take varying amounts of time to reach the goal of resolving Low T symptoms.