bac water 30ml Bacteriostatic (25 pack) – SyringesNeedlesDepot 30ml Bacteriostatic Water (each) –

Alternative solvents include sterile water (no preservative, single-use only), acetic acid water (0.6% acetic acid, used for peptides with poor solubility at neutral pH), and sodium chloride 0.9% (isotonic saline)

The many faces of B12 deciency include neurologic symptoms such as numbness and tingling in the hands and feet, muscle cramps, dizziness, cognitive disturbances, difficulty walking, erectile dysfunction, as well as fatigue and psychiatric symptoms like depression and even psychosis. In addition to these more spectacular symptoms, B12 deficiency over time is associated with a rise in homocysteine in the blood, an amino acid that, when elevated, leads to a hardening and thickening of artery walls

Regarding your first point, I can't find any SOPs or other guidance specifically around stacking

If stomach disturbance is a concern, may be taken with a meal, however, absorption may be decreased

Losing 50 pounds means losing some muscle along with the fat, especially if protein intake is inadequate during the weight loss period