Cyanocobalamin is the man-made version of B-12
Professional IM injections utilize bioactive forms including methylcobalamin and Methyl B12 that require minimal cellular conversion compared to synthetic cyanocobalamin found in most oral supplements
doi: 10.2337/diabetes.47.9.1464
Reported applications include NNMT enzyme inhibition assays measuring 1-methylnicotinamide formation or S-adenosylhomocysteine release, intracellular target-engagement assays in differentiated 3T3-L1 adipocytes where 5-Amino-1MQ reduced intracellular 1-methylnicotinamide with an EC near 2.3 M (Neelakantan et al., Biochem Pharmacol, 2018), membrane permeability and Caco-2 transport characterisation, methyltransferase selectivity panels covering COMT, DNMT1 and PRMT3, and rodent studies of NNMT inhibition in adipose tissue and liver following the antisense knockdown work of Kraus and colleagues (Nature, 2014)
Acupuncture for muscle spasms has a strong evidence base for both neck spasms and low back muscle spasms
Blood tests can determine B12 levels