Once you dissolve our methyl B12 in saline, you’ll need to use syringes with needles so that you can inject it. You can choose syringes designed to deliver the medication either into muscle tissue or into fat tissue (subcutaneously). We prefer subcutaneous, because it is painless, effective, very easy to do by yourself, and carries no risk of nerve injury.
Every day, millions of people around the world inject insulin subcutaneously. This raises the question: Can you use insulin syringes for B12 injections? Absolutely. The needles designed for insulin purposes naturally work very well for B12 shots.
But, even insulin needles vary by size and gauge. All of them will work, but some will just be more comfortable to use. So, what are the best needles for B12 injections?
B12 Injection Needle Size & Gauge
Needle size refers to the length of the needle, which determines its penetration depth and is measured in millimeters (mm). Gauge, on the other hand, refers to the thickness or diameter of the needle, with a higher gauge number indicating a thinner needle. The following are our recommended vitamin B12 injection needle size and gauge:
B12 Shots Needle Size (Length)
For subcutaneous B12 injections, we suggest using shorter 4-5mm needles. This helps minimize the risk of accidentally piercing muscle tissue:
Needles >or=8 mm, inserted perpendicularly, may frequently enter muscle in limbs of males and those with BMI <25 kg/m(2). With 90 degrees insertion, needles 4-5 mm enter the subcutaneous tissue with minimal risk of IM injection in virtually all adults.
Skin and subcutaneous adipose layer thickness in adults with diabetes at sites used for insulin injections: implications for needle length recommendations
Shorter needles are also less painful, because they penetrate less tissue:
The needle lengths that were once recommended for SC injection (for adults, ≥8 mm; for children, ≥6 mm) are now known to be too long because they increase the risk of IM injections without evidence of improved glucose control. Shorter needles are much safer and are better tolerated and less painful.
New Insulin Delivery Recommendations
The 4-mm needle was shown to be safe and efficacious in adult patients of all sizes; skin leakage was equivalent and pain scores were improved with the 4-mm needle. Similar studies have been performed in various other groups, including obese patients.
Traditional subcutaneous needle sizes extend up to 12.7 mm. However, we now know that these long needles are excessive. Research shows that 4 mm needles are effective, less painful, and carry no risk of penetrating muscle tissue, even in lean people.
In general, the shorter the needle, the lower the risk of injecting into muscle by accident, especially in people with minimal fat. And they’re more comfortable to use. When Becton Dickinson introduced their BD Ultra-Fine™ 6 mm needle, they reported that 80% of patients preferred the shorter needles over the 8 mm and 12.7 mm alternatives.
So, if you can find 4 mm or 5 mm needles, we recommend using them. If not, 6 mm or 8 mm needles will also work. Just ensure that you pinch the skin if the injection site is too lean. We advise using the area around the belly button if it has some fat.
Needle Gauge for B12 Injection (Diameter)
The gauge of a needle refers to its diameter and plays a crucial role in both patient comfort and the rate at which B12 is delivered into your subcutaneous tissue.
For instance, a thicker 25G gauge may offer faster B12 delivery but could result in more discomfort. On the other hand, a 30G gauge represents thinner, less painful needles at the cost of slower delivery. When choosing a gauge, consider your skin thickness and the viscosity of the B12 solution; a thicker solution may need a slightly thicker needle.
From our experience, higher gauges like the 30-31G needles from Insumed and BD cause minimal pain, even though they take a few extra seconds to inject. We think it’s worth the tradeoff. However, the choice is personal. For example, our reader Becky prefers 23G:
So, try a few different gauges to find out which one suits you best.
Needle-Free Will Soon Be An Option
If you have a fear of needles, you might soon be able to avoid them by using a needle-free injector. These devices propel liquid through the skin into the fat tissue using high-pressure, allowing you to inject B12 or any other liquid injectable without needles. However, try out 4-6 mm / 30-31G needles first. They’re almost as pain-free.
Conclusion
Based on the current research and our experience, which needles for vitamin B12 injection should you opt for? The best needle for B12 injection into fat tissue would be within the 4-5 mm size range, combined with a gauge of 30G or higher.
The 4 mm needle is long enough to traverse the skin and reach the subcutaneous tissue with minimal risk of intramuscular or intradermal penetration. It’s considered the safest choice for both adults and children, regardless of age, gender, ethnicity, or BMI. And the higher, thinner gauge guarantees as little pain as possible from a needle.
Here are some final tips from the New Insulin Delivery Recommendations paper:
- Ensure that the skin is clean and dry before injecting. Patients usually do not need to use a disinfectant on the skin, but if they do, they should allow it to dry completely before injecting.
- Use needles of shorter length (4 mm or the shortest available) and smaller diameter (highest gauge number), and the tip with the lowest penetration force to minimize pain. Use a sterile, new needle with each injection.
- Insert the needle through the skin in a smooth but not jabbing movement. Pain fibers are in the skin, and going through the skin too slowly or too forcefully may increase the pain.
If you can’t find 4-5 mm needles, 6-8 mm ones can also be suitable as long as you inject into an area with enough fat, such as around the belly button. Pinch the fat when you inject, to prevent accidental muscle penetration, and you should be alright.
Of course, feel free to experiment with various sizes and gauges to know for certain which needles for B12 shots you personally like best.
Best wishes.