Diabetes and the Flu Shot: Is It Safe?

Influenza (the flu) vaccines are safe and effective for people with diabetes, including type 1, type 2, and gestational diabetes. People with diabetes have a higher risk of complications from the flu than the general public.

Getting the flu shot can help reduce your risk of being infected with the influenza virus and complications like pneumonia, sinus infections, reduced control of blood sugar levels, and hospitalization. The flu vaccine can help prevent these outcomes.

This article will review the safety and effectiveness of the flu shot for people with diabetes, its possible side effects, things to know before getting the shot, and risks of the flu for people living with diabetes.

Person with diabetes getting the flu vaccine

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Is the Flu Shot Safe and Effective for People With Diabetes?

Influenza vaccines are safe and effective for people with diabetes. Vaccines must pass rigorous developmental and testing procedures to demonstrate their safety for authorized use in the United States.

The Centers for Disease Control and Prevention (CDC) conducts yearly studies of flu vaccines to see how well they protect people against the flu virus. Effectiveness can vary year to year, but overall, getting the flu vaccine reduces the risk of getting the flu by between 40% and 60% in the general population.

Effectiveness depends on whether the yearly flu vaccine is well-matched with the type of flu virus circulating. But the vaccine does provide a significant level of protection and risk reduction.

In addition to reducing the risk of getting the flu, the flu shot can also help reduce the severity of flu if you do get sick. For those with diabetes, the flu shot has been found to help reduce the risk of cardiovascular events (such as heart attack and stroke) and hospitalization due to the flu.

People who should not get a flu shot include:

  • Babies 6 months of age or younger
  • People with severe, life-threatening allergies to any ingredient in the flu shot (excluding egg proteins; there are other options for that)
  • Those who have had a severe allergic reaction to a previous flu shot

Talk with a healthcare provider if you aren’t sure about whether you should get a flu shot due to medical reasons.

Which Type Should People With Diabetes Get?

There are several types of injectable flu vaccines. For people 65 and older, these include a type with a higher dose of antigen (a substance from the virus that provokes the immune response) and a type with an adjuvant (an additional substance unrelated to the virus that creates a stronger immune response).

There are also egg-free flu vaccines for those who may be allergic to eggs. Talk with a healthcare provider about which one is best for you.

People with diabetes should not get the nasal spray flu vaccine, which is the live attenuated vaccine (meaning it contains live but weakened flu virus). Pregnant people should also not get the nasal spray vaccine. Both of these groups should get an injectable flu shot.

Are There Any Side Effects of the Flu Shot?

Side effects can happen with any medication or treatment. Sometimes, vaccines can cause side effects. Common side effects from the flu vaccine can include:

  • Soreness/redness/swelling at the injection site
  • Headache
  • Low-grade fever
  • Nausea
  • Muscle aches
  • Fatigue
  • Fainting

If you’ve ever had an allergic reaction to a vaccine, let your healthcare provider know.

Risks of Flu for People With Diabetes

People with diabetes (type 1 and type 2, as well as gestational diabetes) are at higher risk of developing flu complications, including hospitalization and death. Complications can include:

About 30% of adults hospitalized with flu have diabetes. Flu can also make long-term health problems, including diabetes, worse. This is because flu can weaken the immune system, making it harder to fight infections.

In diabetes, blood sugar levels must be managed through medication and lifestyle measures to keep them in a healthy range. Influenza can also make it more difficult for your body to control blood glucose levels and impact appetite, causing even more blood sugar fluctuations.

What Should People Avoid Before Getting the Flu Shot?

There's nothing special you have to do before getting the flu shot. Check with a healthcare provider first if you're unsure whether you should get the shot or if there's a specific one that would be best for you.

Talk to a healthcare provider about your symptoms if you're feeling sick. They can advise you to get the flu vaccine or wait until you feel better.

Where Does the Flu Shot Come From?

In the United States, the three different flu vaccine production technologies approved by the Food and Drug Administration (FDA) are:

  • Egg-based flu vaccine
  • Cell-based flu vaccine
  • Recombinant flu vaccine

Egg-based vaccines are the most common way the vaccine is made. The CDC or another approved lab partner provides candidate vaccine viruses (CVVs) to be grown in eggs, per FDA requirements. The CVVs are then injected into fertilized hen eggs and allowed to replicate.

The fluid with the virus is then harvested, the virus is killed or inactivated, and the antigen is purified. Then it is tested and packaged.

In cell-based vaccines, the CDC or a lab partner uses viruses grown in cells to make CVVs, which are then put into cultured mammalian cells (not eggs) and allowed to replicate. The virus-containing fluid is collected and the antigen purified, then tested and packaged.

In recombinant vaccines, there is no CVV to produce—these vaccines are created synthetically. They use a gene from the virus that codes for the antigen to produce the antigen in cell lines. No eggs are used.

Where Can You Get the Flu Shot?

You can get a flu shot at a variety of places, including:

  • A healthcare provider’s office
  • Pharmacies (standalone drugstores or in grocery stores or other retailers with pharmacies, such as Target and Walmart)
  • Urgent care clinics
  • Employer-hosted flu shot clinics

If you’re unsure where to get a flu shot near you, the flu shot finder can help you find a facility near you.

When Should You Get the Flu Shot?

 The American Diabetes Association (ADA) recommends getting the flu shot in September. It takes about two weeks to fully take effect and for you body tomount an immune response. Flu season in the Northern Hemisphere starts in the fall and extends throughout the winter.

While getting the flu shot does not mean you are 100% not going to get the flu, it reduces your risk for about six months.

You should get the flu shot every year. The vaccines are made specifically for the flu strains that are likely to circulate, which change yearly.

Summary

Flu shots are safe and effective for people with type 1, type 2, and gestational diabetes. Flu vaccines can help reduce your risk of getting the flu. It can also reduce the severity of the flu and your risk of getting various diabetes-related complications from the flu.

Talk with a healthcare provider about which type of shot may be best for you. Also, let them know if you’ve had a previous allergic response to the flu vaccine. Aim to get a flu shot in September each year.

A Word From Verywell

Getting the flu vaccine is an easy way to reduce your chance of getting the flu and the risk of serious complications from the flu. If you’re concerned about any aspects of the flu vaccine, talk with a healthcare provider. They’ll be able to answer any questions you have, and address concerns that might be on your mind.

Frequently Asked Questions

  • Does the flu shot affect blood sugar in people with diabetes?

    It might, temporarily. This is because the immune system reacts to the vaccine. If you are achy or have any discomfort from the shot, this can cause blood sugars to rise. But this is typically mild.

    Talk with your healthcare provider about what you might expect. Getting the flu can cause more serious fluctuations in blood glucose levels.

  • What are the side effects of the flu vaccine?

    The vaccine can cause soreness/redness at the site, headaches, fever, nausea, fatigue, and muscle aches. These are temporary. Serious reactions like severe allergic reactions include trouble breathing, wheezing, hives, weakness, dizziness, and a fast heartbeat. Let a healthcare provider know if you have any of these symptoms post-vaccine.

  • How effective is the flu vaccine?

    In the general population, the flu vaccine reduces the risk of flu between 40% and 60%. Flu vaccines can also reduce the risk of hospitalization by half for those living with diabetes.

 

11 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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