HealthCareMagic is now Ask A Doctor - 24x7 | https://www.askadoctor24x7.com

Get your health question answered instantly from our pool of 18000+ doctors from over 80 specialties
159 Doctors Online

By proceeding, I accept the Terms and Conditions

Dr. Andrew Rynne
MD
Dr. Andrew Rynne

Family Physician

Exp 50 years

HCM Blog Instant Access to Doctors
HCM BlogQuestions Answered
HCM Blog Satisfaction

What Causes Weakness Despite Taking Vitamin B12 Injection?

Hi In August this year I was diagnosed as B12 deficient and immediately given injection followed by a first 3monthly in September. I felt no difference in energy levels etc so my GP referred me to hospital consultant to investigate chronic fatigue. I have just been for my next 3 monthly and told there has been a mistake as I have never had a loading dose and therefore need 5 of these every other day for next fortnight. Does this mean that the previous have had no effect without the loading dose? If so this should explain why I am still feeling so tired.
Wed, 11 Jan 2017
Report Abuse
Diabetologist,  's  Response
Hello,

The reasons for weakness can be many. Vitamin B12 deficiency is not necessarily causing weakness. B12 deficiency leads to macrocytic anemia where folic acid deficiency is also associated. Giving high dose vitamin B12 injection on regular basis is not needed, the reason being human body can not store large quantities of it. It will be flushed out through urine. Liver can store just about 1 microgram of B12. So this concept of "loading dose" of B12 is not really there. You may have check if there are other reasons for weakness like Hemoglobin %, presence of diabetes or hypothyroidism.

Hope I have answered your query. Let me know if I can assist you further.

Thanks,
Dr. Prabhakar Laxman Jathar
I find this answer helpful
Note: For further follow up on related General & Family Physician Click here.
Disclaimer: These answers are for your information only and not intended to replace your relationship with your treating physician.
This is a short, free answer. For a more detailed, immediate answer, try our premium service [Sample answer]
Share on
 
Loading Online Doctors....
What Causes Weakness Despite Taking Vitamin B12 Injection?

Hello, The reasons for weakness can be many. Vitamin B12 deficiency is not necessarily causing weakness. B12 deficiency leads to macrocytic anemia where folic acid deficiency is also associated. Giving high dose vitamin B12 injection on regular basis is not needed, the reason being human body can not store large quantities of it. It will be flushed out through urine. Liver can store just about 1 microgram of B12. So this concept of loading dose of B12 is not really there. You may have check if there are other reasons for weakness like Hemoglobin %, presence of diabetes or hypothyroidism. Hope I have answered your query. Let me know if I can assist you further. Thanks, Dr. Prabhakar Laxman Jathar