Choosing the correct needle gauge size (G) is crucial for safe and effective medication delivery. According to the NCBI, using the right gauge ensures accurate dosage and patient comfort. Remember, needle gauges work inversely: the lower the gauge number, the wider the needle—for example, an 18G needle is wider than a 25G. Smaller, higher-gauge needles (like 25G or 26G) generally offer a more comfortable injection, but the right size depends on the medication’s viscosity and the type of injection (intramuscular, subcutaneous, etc.). Always select the gauge based on medical need, not just comfort.