can b12 injections make you nauseous Why do I feel worse after a injection? Vitamin B12 Side Effects Stomach:

1 Mecobalamin 50 mg or placebo was administered intramuscularly twice weekly for 16 weeks to 130 ALS patients who had suffered from ALS for less than one year, were classified as definite, probable, or probable-laboratory supported according to the Updated Awaji Criteria, had an ALS severity rating of grade 1 or 2, had a decrease of 1 or 2 points in the total score on the Revised ALS Functional Rating Scale-Revised (ALSFRS-R) 12 weeks prior to administration, and had a forced vital capacity (%FVC) of more than 60%

Some weight loss clinics include B12 injections as part of their weight management programs, often in combination with other treatments such as a healthy diet and exercise

Vitamin B12 injections are typically administered by a healthcare professional (doctor, nurse) into a muscle (intramuscularly)

Novel small molecule inhibitors of nicotinamide N-methyltransferase (NNMT)