is vitamin b12 injections subcutaneous or intramuscular Optimal Injection Sites for Maximum Absorption and Benefits Cyanocobalamin Injection, USP Rx Only

B12 deficiency may rarely cause blue-grey hyperpigmentation or nail thinning, though nail changes are uncommon

[6] [25] At levels only slightly below normal, deficiency can result in fatigue, headaches, feeling faint, rapid breathing, pale skin, numbness or tingling, poor appetite, heartburn, poor balance, difficulty walking, poor reflexes, blurred vision, memory problems, depression, irritability, inattention, cognitive decline, dementia, and even psychosis

It is also effective for neuropathy, delayed wound healing, scurvy, and symptoms like weakness, fatigue, and reduced immunity caused by vitamin deficiencies

Participants receiving higher doses achieved average weight loss of up to 24% over a 48-week period

0.8 kg in placebo over 24 weeks) that did not meet the magnitude needed for regulatory approval