Frequent Question/Answers



There are a number of medications that you may need to inject at home, including fertility drugs, vitamin B12, hormones, insulin, cancer medications, and epinephrine for an severe allergy reaction. You might need to administer the medication to yourself, administer medication to a family member, or you may need to have a family member learn how to inject you with your medicine.

The most important thing to keep in mind when you need to give yourself or someone else an injectable medication is that the prescribing medical professional undoubtedly welcomes questions if you get stuck figuring out which size needles or syringes to use or how to use them properly.

Which Needle should I use for Testosterone Injections?

LENGTH:The needle used to inject should be long enough to penetrate through the subcutaneous tissue into the muscle mass, or the patient will have more pain.
GAUGE:The typical needle gauge used to inject testosterone is between 22 and 25.

Our facility sells Testosterone IM Kits Click Here

What color needle is used for intramuscular injections?

Needles should be long enough to penetrate the muscle but still allow a quarter of the needle to remain external to the skin. In an adult, needle choice is usually green (21 gauge) or blue (23 gauge). For children a blue is the obvious choice. 

Intramuscular injections. The deltoid muscle is most often used as the site for IM injections in adults: Needle length is usually 1–1½", 22–25 gauge, but a longer or shorter needle may be needed depending on the patient's weight.

What size needle is used for b12 injections?

In general for IM (intramuscular) B12 injections you would use a 23 to 25 gauge needle 1 inch long for an adult.

For SQ (subcutaneous) injections you would typically use a 25 to 27 gauge needle 1/2 to 5/8 inches long.



Choosing the Best Syringe and Needle Size for an Injection

Syringe Sizes

Syringes are labeled based on how much liquid they can hold, and there are different ways in which syringe capacity can be measured. Syringe capacity can either be labelled in milliliters (mL), the term used to describe liquid volume, or cubic centimeters (cc), which describes the volume of solids. Whatever measurement is used, the volume is the same: 1 cc equal 1 mL.

If you will be injecting a medication at home, you need to make sure that you select a syringe that will hold the amount of medication you've been prescribed.

For example, if you're supposed to give yourself 3 cc (3mL) of a drug, you should be sure to get a syringe that holds exactly 3 cc or just a little more than 3 cc. If you use a syringe that holds only 2 cc, you would have to inject yourself more than once, which is unnecessarily painful.

Needle Sizes

Needles are labeled differently than syringes. The packaging will have a number, then a "G," and then another numberWhen determining needle size, note that the first number in front of the letter G indicates the gauge of the needle. 
The higher the number, the thinner the needle. The second number indicates the 
length of the needle in inches.

Needle Gauge

If you will inject yourself with a small amount of medication, a thin, high-gauge needle is fine and should cause less pain than a wider, low-gauge needle. For larger amounts of medicine, however, the latter option is better.

While it may cause you more pain, it will deliver the injection far faster than a thin, high-gauge option. If you have smaller-than-average veins, you may need a thinner needle.

Needle Length

There are two main types of shots that are used at home. Some medications are well absorbed superficially, directly underneath the skin, and others are absorbed in
the muscles:
  • Subcutaneous injections go into the fatty tissue just below the skin. Since these are relatively shallow shots, the needle required is small and short—typically one-half to five-eighths of an inch long with a gauge of 25 to 30.
  • Intramuscular injections go directly into muscle. Muscle is deeper than the subcutaneous layer of skin, so the needle used for intramuscular injections must be thicker and longer. The size needles that usually are best are 20 or 22 G needles that are an inch or an inch-and-a-half-long. For these injections, you must pay attention to the amount of body fat the needle has to go through. Someone who's thin can usually use an inch-long needle, while a person who's on the heavier side may need to use an inch-and-a-half-long needle.