best size needle for vitamin b12 injections Ulove Prs 12 Pack 1ml Industrial Syringes with 25Ga 1 Inch Needle, Plastic Disposable Syringe and Scientific Labs, Liquids Refilling and Measuring : Industrial & Scientific What needle size is best

If the needle is too short for the person, or the angle is wrong, the dose can end up in subcutaneous fat, where absorption is slower and less predictable

A blood test that checks your B12 levels can rule out or confirm that a vitamin deficiency is the cause

160-200 pounds (72-90kg): The standard 400mcg daily protocol works well for most individuals in this range

We test as needed after that

The dose simply not working An incorrect dose, or one that mostly landed in fat, may mean your symptoms do not improve as expected

8,9 Manifestations Vitamin B 12 deficiency affects multiple systems, and sequelae vary in severity from mild fatigue to severe neurologic impairment 1,2,6,10 (Table 2 4,10 )