BOSTON (CBS) — Dr. Mallika Marshall is answering your coronavirus vaccine-related medical questions. If you have a question, email her or message her on Facebook or Twitter.

Dr. Mallika is offering her best advice, but as always, consult your personal doctor before making any decisions about your personal health.

Sally says she received the Pfizer vaccine in March, but before the vaccine she had a “complete physical.” She says her blood sugar was “normal before the vaccine but elevated after the vaccine.” She wants to know if it was a bad reaction to the vaccine.

There have been reports of blood sugars rising temporarily in people with diabetes after getting vaccinated. People with diabetes should monitor their blood sugars in the days after vaccination and call their doctors if there are any significant changes.

Guy asks, “If I had Covid-19 in March 2020 and my quantitative antibodies are currently greater than 250, why do I need to be vaccinated?”

The FDA has recently said that antibody testing should not be used to determine whether someone is immune to the coronavirus or not. It’s still not clear what level of antibodies is sufficient nor how long those antibodies will last. That will take more time to tease out. So even if you’ve had COVID and have evidence of antibodies in your blood, you still should get vaccinated to optimize your protection against future infections, including emerging variants.

John says, “I had the virus and then had the antibody infusion. How does the infusion affect my own produced antibodies?”

It’s not clear. That’s why if you’ve received monoclonal antibodies for a COVID-19 infection, you should wait 90 days before getting the vaccine. You will already have circulating antibodies in your system which could interfere with the effects of the vaccine.

Sara asks, “My concern is if I do get the vaccine will it cause bad effects to the heart? I was recently diagnosed with a PFO. I did ask the cardiologist and he said I should. I also have high blood pressure and diabetes.”

You should definitely follow the advice of your cardiologist. Based on what you’ve mentioned, there is no reason to be concerned that the vaccine is going to have an adverse effect on your heart. But we do know that COVID-19 could have devastating effects on your body, including your heart, especially given that you have diabetes.

Dr. Mallika Marshall