b12 for injection Vitamin Cyanocobalamin 1,000 mcg, 25/Box (Rx) — Mountainside Medical Cyanocobalamin (B12) Injection - Wells

Injectable B12 bypasses the digestive tract, ensuring superior absorption compared to oral supplements

Your doctor will look at how you're doing and might suggest switching to less frequent doses, maybe every two to four weeks

The Infusion: Most drips take about 3045 minutes

Patients with Normal Intestinal Absorption Where the oral route is not deemed adequate, initial treatment similar to that for patients with pernicious anemia may be indicated depending on the severity of the deficiency

In other words, the schedule is a sensible default that a clinician can adjust, not a fixed rule you should try to bend on your own