Which Insulin Size is Best to Use

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The gauge and length of needles is used to determine their thickness. Doctors advise needles to be between 4 to 6 millimeters long. There's no reason why you should use a needle longer than 8 millimeters, for almost all body types. A needle which is too long may be too deep and deliver intramuscular injections. Insulin injections into muscle can increase insulin absorption and possibly lead to hypoglycemia.

The past was when people believed that the needle's size was to be adjusted to the person's weight, which means obese people needed longer needles. A longer needle might be beneficial to some who have weight issues or other medical conditions such as arthritis, but recent studies have shown that the weight of the body does not impact needle effectiveness, according to an article that was published in Diabetes Spectrum.