What sizes of insulin syringes are available, and what is the difference? ... The higher the gauge, the thinner the needle. They are typically available in sizes ranging from 28–31.

The size of the barrel determines how much insulin a syringe holds, and the needle gauge determines the needle thickness. Thinner needles may be more comfortable to inject for some people.

However, the review does conclude that severe and non-severe local reactions probably occur less frequently when 25mm (either 23G or 25G) needles are used to administer DTwP combination vaccines to ...

To determine whether needle size influences a patient's perception of pain, 50 patients requiring hormonal manipulation for prostate cancer were blindfolded and randomised to receive two goserelin ...

To administer a local anesthetic agent, you will need 1% or 2% lidocaine, a 10-ml syringe, and one small-gauge needle (size 25); for anesthetizing deeper layers of tissue, you will also need one ...