Where should I inject insulin?

The most effective and common sites for injecting insulin or placing a Continuous Glucose Monitor (CGM) sensor are areas with a healthy layer of subcutaneous fat. This includes the abdomen (staying at least two inches away from the belly button), the outer thighs, the back of the upper arms, and the upper buttocks. Injecting into fat ensures the insulin is absorbed at a steady, predictable rate. If you accidentally inject directly into muscle tissue, the insulin will be absorbed far too quickly, which can lead to a sudden, dangerous drop in blood sugar. Rotating your injection and sensor sites is absolutely critical. If you repeatedly inject into the same two-inch area, the tissue becomes traumatised. Over time, this leads to lipohypertrophy—the buildup of hard, rubbery scar tissue and fat deposits beneath the skin. If you inject insulin into this scarred tissue, the absorption rate becomes highly erratic; sometimes it absorbs immediately, and other times it pools and absorbs hours later, causing massive blood sugar rollercoasters. Always visualize a grid and rotate your sites daily.