Depending on which area that gets injected. The larger the muscle mass the more often it can be pinned. The glutes and quads have more surface area so you can rotate around those areas more often. I would not inject an IM site more than once every two days. This just allows the site to first and foremost disperse the material and secondly to heal. You can "blow" a site, meaning injecting too much material into one area. What will happen is the material will seep between the layers of skin and muscle and an abscess will form or even worse and infection. This is most often seen in the arms of steroid users who inject too much oil into the delts or triceps. Try not to go over 1-1.5mls in these smaller muscles or you risk fully inflamming the arm. Look it up if you don't believe me. The entire appendage will swell up for a week or more while the cmpds disperses between layers of skin. The larger areas (glutes, lats, quads can handle 2-3mls. If you are injecting a large volume like that do not inject one area more than once every 5 days. These are guidelines I use for injecting vaccinations and such for my line or work. Hope this helps.