The deficiency is so rare in humans that there isnt much information available on the symptoms of the condition
Important safety warning seek urgent medical attention if you experience any of the following: Severe or persistent abdominal pain (which may indicate acute pancreatitis) Right upper quadrant pain, fever, or jaundice (which may indicate gallbladder disease) Reduced urine output, dizziness, or signs of dehydration (which may indicate acute kidney injury) Severe nausea or vomiting preventing adequate fluid intake Signs of a serious allergic reaction (swelling, difficulty breathing, rash) Symptoms of hypoglycaemia such as dizziness, sweating, or confusion These may represent serious adverse effects requiring prompt clinical assessment
These Warrant Pulling Back Nausea affects your ability to eat adequately for more than a week
At 20 mg/ml, that is 0.1875 ml, or about 18.75 units
A simple blood panel will confirm your vitamin B12 levels and then your provider can develop a plan of action from there