Is It Safe To Take Heptatitis B Vaccine Again If I Have Taken It Already?

Posted on Wed, 22 Aug 2012

Medically reviewed by Ask A Doctor - 24x7 Medical Review Team

Wed, 22 Aug 2012 Answered on

Sat, 8 Sep 2012 Last reviewed on

Question : I am not sure if I took the Hepatitis B vaccine before or not. Is it safe to go for vaccination now (even if I took it already)?

Answered by Dr. Ioan Dorian OANA (18 minutes later)

Hi XXXXXXX

Thanks for your query.

Hepatitis B immune globulin (HBIG) alone or in combination with vaccine (if not previously vaccinated) is safe and effective in preventing HBV infection after an exposure, but should not be seen as an alternative to a strategy of prevention of transmission.

The vaccine is not needed for those people who have HbsAg or hepatitis B surface antibody (anti-HBs), but it should not be delayed while awaiting blood test results, so my recommendation is to take the Hepatitis B vaccine as soon as possible if you haven't done those blood test yet.

If you have any more queries, feel free to ask.

Regards
Dr. Dorian Oana MD, PhD

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar

Follow up: Dr. Ioan Dorian OANA (6 minutes later)

Doctor, my question is whether it is safe to take the vaccine twice as I am not sure if I have taken it already?

Answered by Dr. Ioan Dorian OANA (9 hours later)

Hi XXXXXXX

Thanks for your reply.

I apologize for the misunderstanding. However the answer to your question has been included in my previous answer too.

I was saying "The vaccine is not needed for those people who have HbsAg or hepatitis B surface antibody (anti-HBs)". So, in this case you should do blood tests and check HbsAg and hepatitis B surface antibody (anti-HBs).

If you have any of these 2, you do not need the vaccine. If you have neither, then you need the vaccine.

If you have any more queries, feel free to ask.

Regards
Dr. Dorian Oana MD, PhD

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar