Flu Shots and Diabetes: What You Need to Know 

When you live with diabetes, staying healthy during flu season is especially important. The flu can raise your blood sugar, make managing diabetes more difficult, and increase your risk of serious illness.  

The best prevention effort? An annual flu shot.  

Here’s a rundown of all you need to know about flu shots and diabetes. 

What Is In a Typical Flu Shot? 

A flu shot helps your body learn how to fight off the flu virus by introducing inactive or harmless parts of the virus, which triggers an immune response without causing illness. This process trains your immune system to create specific antibodies that can recognize and attack the flu virus if you’re exposed later, providing protection or reducing the severity of illness. 

There are several types of flu vaccines available, and your healthcare team can help you determine which option is best for you. Most insurance plans—including Medicare and Medicaid—cover flu shots at no cost. Protection typically begins about two weeks after vaccination and lasts for around six months. 

Flu vaccines are available through healthcare providers and many local pharmacies. You can find a convenient location near you by visiting VaccineFinder.org. 

Flu shots typically contain: 

• Inactive parts of the flu virus that teach your immune system how to respond.  A flu shot does not give you the flu. 

• A small amount of preservative. This helps keep the vaccine safe and effective by protecting it from germs, especially during storage. Flu vaccines are currently available in both preservative-containing versions (typically for multi-dose vials) and preservative-free versions. 

• A small amount of stabilizers and adjuvants: Some flu vaccines contain stabilizers, such as a small amount of sugar, which help protect the vaccine from heat and light, keeping it potent. Certain vaccines also include an adjuvant, a substance that enhances the body’s immune response. Aluminum salts are a common type of adjuvant used for this purpose. 

Because the flu virus changes every year, the medical community updates the vaccine to match the strains most likely to spread. Each year, a new flu vaccine is developed based on scientists’ predictions of which strains will be most prevalent. When the vaccine is well-matched to circulating viruses, it can reduce a person’s risk of illness by 40–60%. 

Side Effects of the Flu Shot – And What To Expect If You Have Diabetes 

Most people, including those with diabetes, handle the flu shot well. Common side effects include soreness or redness in your arm, low fever, tiredness, headache and body aches.  

These side effects are mild and usually last one to two days. They are signs that your body is building protection. If these symptoms persist or are severe, contact your healthcare team.  

How Side Effects Can Be Different for People Living With Diabetes 

People living with diabetes can experience the same side effects as those living without diabetes, but there are a few differences to keep in mind…  

• Blood sugar may rise temporarily. When your immune system responds to the flu shot, your body may release stress hormones. These hormones can raise blood sugar for a short time. This does not happen in people living without diabetes the same way. 

• Side effects may feel more intense if your blood sugar is already high. High blood sugar can make your body more sensitive to stress or illness. 

• Dehydration can happen more easily. Mild fever or aches may make you drink less water, which can affect blood sugar. 

In most cases, these changes are small and short-lived. Checking your numbers a little more frequently for a day or two can help you stay in control. 

How the Flu Shot Affects Your Diabetes Diagnosis 

A flu shot cannot change your diabetes diagnosis or make your diabetes “worse” whether you have type 1 or type 2. What it can do is temporarily affect your blood sugar levels, as previously discussed. It may make it feel like your diabetes is acting differently for a day or two. Once the response settles, your blood sugar should return to its usual pattern. 

If you experience these effects and your blood sugar stays high or low for several days, check in with your care team. 

When Is the Best Time To Get the Flu Shot? 

Ideally, you want to get your flu shot before cold weather sets in. This timing has less to do with the temperature itself and more with the fact that colder weather brings people indoors, increasing the transmission of the flu. By getting your flu shot early, you give your body time to build strong protection before the flu becomes widespread. 

The American Diabetes Association recommends that people with diabetes get a flu shot every year in early fall—ideally by the end of October—but it’s still beneficial to get vaccinated in November or even December. Flu season typically peaks between December and January but can extend into March or April. It’s also recommended that everyone in your household receives a flu shot to help reduce the spread of the virus. 

That said, even if you’re into the cold weather, it is still helpful to get the vaccine! As long as the flu is circulating, the shot can protect you from serious illness. 

Flu Shots for Children and Older Adults With Diabetes 

Children With Diabetes 

Children with diabetes should get a flu shot every year starting at six months old. It helps prevent severe illness, high blood sugar caused by infection, and hospital stays. Some young children may need two doses the first year they get the flu shot, depending on their age and vaccine history. 

Adults and Seniors With Diabetes 

All adults with diabetes should get a flu shot each year. Adults 65 and older may receive a high-dose flu shot because their immune system needs a stronger signal to build protection. This is safe for people living with diabetes. 

There are no age limits that prevent people with diabetes from getting the flu shot. 

Are There Any Restrictions or Reasons To Wait? 

Most people living with diabetes can safely receive flu shots. Still, you should talk to your doctor if: 

• You have had a severe allergic reaction to a previous flu vaccine 

• You are very sick or running a high fever 

• You have an allergy to any ingredient in the vaccine 

Diabetes itself is not a reason to skip the flu shot. In fact, people with diabetes are strongly encouraged to get vaccinated every year. Diabetes can make recovering from the flu more complicated due to fluctuating blood glucose levels and a weakened immune system. Getting vaccinated helps prevent infection and can also reduce the severity of illness if you do get sick. 

Keeping Yourself Protected 

A flu shot is one of the simplest and most effective ways to protect your health when you are living with diabetes. It lowers your risk of serious illness; Helps maintain more stable blood sugar by reducing the severe spikes and drops that can occur when a person with diabetes contracts the flu. Getting vaccinated helps prevent infection, reduce the severity if you do get sick, and avoid more serious health complications. Whether you are caring for yourself, your child, or an older adult living with diabetes, getting a flu shot each year is an important step in staying well. 

As always, with questions, contact your healthcare providers.  

Author: Connie Ely, Pharmacist | CCS Health       

This site is for educational purposes only. Talk to your doctor or healthcare provider before making any decisions about your health.