Vitamin B12 is needed after gastric sleeve surgery, I need help with dosage.

vitamin b 12 supplementation after a bariatric procedure will depend on the type of procedure, whether it is restrictive or malabsorptive.

the gastric sleeve is a procedure classified among the restrictive ones, since it does not change the way your digestive system works, so it would not be necessary the supplementation of these vitamins since the absorption zone of these vitamins in the gastrointestinal tract is not affected.

Gastric sleeve patients do not need to be on vitamin B12 after the surgery.  Only some gastric bypass patients do.  If you do not have any B12 issues right now, you will not need B12 after your gastric sleeve.  The only B12 issue I find most often in my sleeve patients is that their B12 is too high from taking B12 when they do not needed.  After a gastric sleeve, you will need to be on a good bariatric multivitamin, and a healthy balanced diet.