Should you get a flu shot 💉 while taking prednisone 💊 or not?

A Prednisone Warrior’s wife asked me,

“My husband is on Prednisone. Should he get a flu shot or not? And if so, what dose?”

Discover how I responded to these and other questions about prednisone and the influenza vaccine by watching the following video or reading the article below. 

Watch now!

Once upon a time, I gave 200 flu shots in one day! Phew! I’ll never forget it.

Full disclosure: I am a certified immunizer. Although it’s been a while since I’ve given one, I have given lots of flu shots in my pharmacy career. In addition, I believe in following the guidance from the CDC and expert organizations–check out my summary of quotes from their official statements on prednisone and the flu shot at the end of this article.

Should I get a flu shot while taking prednisone?

First of all, should you get a flu shot or not? It’s kind of confusing because prednisone can cause immunosuppression. So does that mean you shouldn’t get flu shots? Here’s the answer: there are different kinds of flu vaccines.

1. Nose Spray (Avoid this on Prednisone): There’s the nasal spray (FluMist) and that is a live vaccine. It’s made of a live attenuated influenza virus and that one isn’t really safe for people on prednisone. Everybody on prednisone should pretty much avoid the nasal spray.
2. Injection: The injection, the vaccine that goes in your arm, that one should be safe for people on prednisone because it’s not a live vaccine. It’s what they call inactivated. It’s like a killed virus and so it’s not as harmful for people on prednisone.

In fact the injection of the vaccine is really good because it helps you to prevent what could be potentially fatal: the flu. You do not want to get the flu while you’re on Prednisone because you’d have a harder time fighting it. You have a higher risk of pneumonia and other influenza complications because you are on prednisone.

Is there an interaction between prednisone and the flu vaccine?

No, there is not an interaction between prednisone and the injection of inactive influenza virus vaccine.

Should I get a high-dose flu vaccine or not?

The only people who really need the high-dose vaccine are over 65 years old. This Prednisone Warrior who sparked this article by asking the question is over the age of 65 and so yes, he should get the high-dose influenza vaccine because of his age. You can get the high-dose vaccine if you’re over 65 and that should be fine even if you’re taking prednisone.

Does it matter which dose of Prednisone to get the Flu Shot? Or when is the best time to get the flu shot?

Short Term and Low Dose Prednisone

If you are taking Prednisone for less than two weeks and a dose of less than 20 mg, then you should wait until you are done taking the prednisone before you get the vaccine. The only people who should wait are those who will be finishing prednisone within two weeks.

<20 mg + <2 weeks = wait until you’re done with prednisone.

High Dose or Long Term Prednisone

If you are on any other dose (over 20 mg or taking prednisone longer than two weeks), there’s no reason to wait to get your flu shot. For those who are going to be taking prednisone longer than 2 weeks, get your flu vaccine without delay (see below the best month). Get that protection in you!

>20 mg or >2 weeks of prednisone = get the flu shot.

<20 mg and >2 weeks of prednisone = get the flu shot.

When should you get your flu vaccine?

September and October is a good choice for most people on prednisone. Don’t get the vaccine in July or August if you’re over 65, instead, wait until September or October.

When is the flu vaccine most effective? 

It is very most effective if you get it in October. If you do get it before October, then you’re ready for the beginning of the flu season. But getting the vaccine in October gives you six months of flu season coverage lasting through April. There’s not a lot of evidence that the flu shot lasts longer than 6 months, so if you get it in August, the protection is going to start running out in February. The flu season continues through April, so you have two months that you still need to fight. So the very, very best time is October because you’re getting it right before the flu season gets strong but enough time that it’s going to last throughout the flu season.

Can I get the COVID Vaccine at the same time as the Flu shot?

Yes, they are fine to be given together. In fact, they are currently testing a one-shot option that would contain both flu and Covid vaccines in one vial.

Flu Shot & Covid Shot: How long after should I restart prednisone?

A Prednisone Warrior asked: “I just got a Flu shot and a Covid refresher shot. Could you please tell me how long I should wait before I will be able to start with a new course of prednisone?”

Check out this video for my answer for how long to wait to restart prednisone after a flu shot.

Does the flu shot give the flu?

The answer is no. But do some people feel “flu-ish”? Yes. It is common to have a very slight fever. The flu shot can make you feel like you have the flu, but it’s not actually the flu. It’s just your body’s immune response to the vaccine, and that is to be expected. Your immune system is doing its job against the vaccine and so no, that is not the flu. It’s working. Definitely report if you’re getting an extremely high fever or extreme symptoms.

It’s kind of how the COVID mRNA vaccines can make you feel awful as your body makes the immune response. The COVID mRNA vaccines aren’t giving you a COVID infection. Instead, the achy joints, fever, headache, and other vaccine side effects are actually a sign that your body’s immune system is working hard to build the weapons it will use to fight a future infection. Those are called antibodies.

Does the flu vaccine sometimes not work?

When they make the flu vaccine, the scientists have to guess about a year to six months in advance of the flu season what the flu is going to look like in the upcoming flu season. That means they have to guess how the virus is going to replicate. That’s the kind of tricky to do and they can guess wrong. It’s all based on what the flu was like on the other side of the world, in the Southern Hemisphere. During their winter, which is our summer, the flu passes around and mutates.

Sometimes by the time the flu virus has traveled all the way to the Northern Hemisphere it’s changed so much that it doesn’t match anymore. Some years it’s a really great match and you’re really glad you got your flu shot. Other years it does not match as well. In that case, the vaccine protects you from a virus that is no longer circulating. The new virus can make you sick.

It doesn’t mean the flu vaccine doesn’t work. Instead, it means the match that season failed. Humans are trying to predict virus behavior, and that’s really hard to do, and sometimes the scientists’ best guess didn’t match.

2023-2024 Flu Vaccines

The CDC published these updates to the flu vaccine for the 2023-2024 season.

“The 2023-2024 season U.S. flu vaccines will contain an updated influenza A(H1N1)pdm09 component:

• A/Victoria/4897/2022 (H1N1)pdm09-like virus for egg-based vaccines and
• A/Wisconsin/67/2022 (H1N1)pdm09-like virus for cell-based or recombinant vaccines.

How well flu vaccine works can depend in part on the match between the vaccine viruses and circulating viruses. Preliminary estimates show that last season, people who were vaccinated against flu were about 40% to 70% less likely to be hospitalized because of flu illness or related complications.”

Finally, am I going to get the flu vaccine?

Yep! I’m taking all my kids in October to get our flu shots. Why? Because I have no desire to have a bunch of kids with the flu and wondering whether they have flu or Covid! Plus since the last few years’ flu seasons ended up being mild, this year’s flu may be much worse.

So… are YOU going to get your flu shot?

Want a 1-page Printable version of tips for coping with vaccine side effects?

I have a little printout of all the ways to feel better that I suggested in my article about Covid Vaccine Side Effects. Most of it should apply to flu vaccine as well! So if you would like a copy of that, enter your email in the form below asking for a copy of the Vaccine Side Effect Tips and I will send you an email with all of those tips. It’s a one-sheet printout summarizing all of my best vaccine side effect coping tips.

Official Scientific Statements on Prednisone and Influenza Vaccine

The following are direct quotes from official sources regarding prednisone, immunosuppression, and the influenza vaccine.

CDC Statement: What is Immunosuppression?

A substantially immunosuppressive steroid dose is considered to be ≥2 weeks of daily receipt of 20 mg or 2 mg/kg body weight of prednisone or equivalent.

Two conditions are temporary contraindications to vaccination with live vaccines: pregnancy and immunosuppression.

Use of aerosolized steroids, such as inhalers for asthma, is not a contraindication to vaccination; nor are alternate-day, rapidly tapering, and short (less than 14 days) high-dose schedules, topical formulations, and physiologic replacement steroid dose schedules.

CDC Statement on Immunocompromised Persons

Immunocompromised persons should receive an age-appropriate IIV or RIV4.
LAIV4 (nasal spray) should not be used for immunocompromised persons.
Immune response to vaccines might be blunted in immunocompromised persons, and might be reduced or minimal as a result of medications, chemotherapy, or transplant regimens.
Timing vaccination during some period either before or after interventions which compromise immunity may be appropriate. The Infectious Diseases Society of America (IDSA) has published guidance concerning the timing of vaccination in relation to such interventions.

CDC Statement on Corticosteroids like Prednisone

The amount of systemically absorbed corticosteroids and the duration of administration needed to suppress the immune system of an otherwise immunocompetent person are not well defined. Although the immunosuppressive effects of steroid treatment vary, the majority of clinicians consider a dose equivalent to either ≥2 mg/kg of body weight or ≥20 mg/day of prednisone or equivalent for persons who weigh >10 kg when administered for ≥14 consecutive days as sufficiently immunosuppressive to raise concern about the safety of vaccination with live-virus vaccines (37). This dosage is referred to as “high-dose corticosteroids”.

Corticosteroids used in greater than physiologic doses also can reduce the immune response to vaccines. Vaccination providers should defer live-virus vaccination for at least 1 month after discontinuation of high-dose systemically absorbed corticosteroid therapy administered for ≥14 days. Following vaccination, the decision needs to be made when to restart immunosuppressive therapy. There are no specific recommendations about when to restart immunosuppressive medicines. However, when initiating immunosuppressive therapy, providers should wait 4 weeks after a live vaccine and 2 weeks after an inactivated vaccine. However, if patients require therapy for chronic inflammatory conditions, this therapy should not be delayed because of past administration of vaccines.

Corticosteroid therapy usually is not a contraindication to administering live-virus vaccine when administration is 1) short term (i.e., <14 days); 2) a low to moderate dose (i.e., <20 mg of prednisone or equivalent per day or <2mg/kg body weight per day for a young child); 3) long-term, alternate-day treatment with short-acting preparations; 4) maintenance physiologic doses (replacement therapy); or 5) topical (skin or eyes), inhaled, or by intra-articular, bursal, or tendon injection. No evidence of an increased risk for more severe reactions to live, attenuated viral vaccines has been reported among persons receiving corticosteroid therapy by aerosol, and such therapy is not a reason to delay vaccination.

Study on Children and Influenza Virus

Prednisone bursts did not diminish the response of asthmatic children to the 1996 influenza virus vaccine, compared with controls. Children can be effectively vaccinated against influenza virus while they are receiving prednisone therapy bursts for asthmatic exacerbations.

Read more…

• Should I Get the COVID Vaccine? 💉
• COVID Vaccine Side Effects for People on Prednisone
• Why I changed my mind about the COVID Vaccine (it’s not what you think)
• Prednisone Side Effects: The Ultimate List