Also, since you need stomach acid to absorb B12, long-term use of acid-suppressing proton pump inhibitors (such as Nexium, etc.) can lead to B12 deficiency, as can chronic intestinal conditions such as Crohns disease, celiac disease, and intestinal parasites
With the BPC 157 application (Sikiric et al., 1993
2 mL equals 200 units on a U-100 insulin syringe, or two full 1 mL syringes drawn and added to the vial
However, in rare cases, very high doses may lead to mild side effects such as headaches, nausea, diarrhea, or skin reactions like itching and rashes
Faster Absorption Bypasses the digestive tract, making injections useful for low dietary intake, absorption issues, or medications that reduce B12 uptake