Anticipate how the animal could respond to an injection and assure yourself that the animal's reaction to the injection will not lead to injury to yourself or to others. Do not place yourself at needless risk of injury for the sake of an injection. If you cannot give the medication safely, don't give it. The volume of drug administered at an injection site depends not only on the dosage of the medication but also on the route of administration and the maximum volume recommended per site. Always follow the label recommendations for dosage and volume per injection site unless directed to do otherwise by your veterinarian.
Injection needles are available in varying lengths and diameters.
The diameter of a needle is measured by its gauge. The larger the gauge, the smaller the diameter of the needle. Needles used for subcutaneous injection should be 1 inch or less in length for any age animal. Use only needles with aluminum hubs because they are less likely to break during injections. Do not use needles with plastic hubs.