When you go through a clinic and a licensed compounding pharmacy, that chain of custody is built in you're not trusting an anonymous website's claim about what they shipped
This area is easy to reach and less likely to cause discomfort compared to more muscular injection sites
People who eat animal products can still obtain B12 through their diet but it is harder for vegetarians and vegans
MOTS-c MOTS-c: Mitochondrial-derived exercise mimetic peptide
Side Effects: Itching Rash Hives Swelling of face, lips, tongue, or throat Difficulty breathing Dizziness or headache (mild) Nausea or upset stomach (mild) Low potassium levels (hypokalemia, rare with prolonged use) Dosages: Vitamin B12 Deficiency Treatment:Initial treatment dosages often range from 1000 mcg to 5000 mcg injected intramuscularly.Frequency might start with injections every other day or once a week, depending on the severity of the deficiency.Once levels improve, the frequency may be reduced to maintenance injections, typically once a month

Symptoms of B12 deficiency include: Low energy and fatigue Digestive problems Depression and moodiness Insomnia Brain fog and memory loss Anemia Reduced immune system function Tingling or numbness in the extremities Swollen tongue Loss of vision or hearing Jaundice Kidney disease Pale skin Poor circulation in the extremities If you are over age 50 and are experiencing one or more of the above symptoms, boosting your intake of B12 cannot hurt, and it may provide a safe and inexpensive solution while preventing a wrong diagnosis