Scientific References Frequently Asked Questions How long does it take to feel better after a B12 injection
Other side effects that can occur include: Excessive sweat production Rapid weight gain Pain when breathing Shortness of breath when lying down Anxiety Increased or irregular heart rate Numbness, tingling or muscular weakness Increased thirst Urinary frequency B12 injections can also cause allergy symptoms immediately after administration, like difficulty breathing, a swollen throat, mouth, or swelling of the mouth, tongue or face
How quickly do B12 injections work
If simple measures do not provide relief within two to three weeks, further medical review is appropriate to exclude other causes and consider alternative supplementation routes
Then theres the placebo effect
Intravenous B12 Dose Considerations Healthcare providers must think carefully about Vitamin B12 IV doses