Three things you shouldn't do after the flu shot, according to doctors

Medical Advice

Express newspaper

09/10/2025 19:26

Around 30 million people in the UK and millions more around the world receive the flu vaccine every winter.

Doctors emphasize that the vaccine is safe and effective, but some common habits can negatively affect its effectiveness or make you feel worse after receiving it.

Who is the flu vaccine recommended for?

It is mainly recommended for: people over 65, pregnant women, and those with weakened immune systems.

Studies show that the vaccine can cut the risk of getting the flu by more than half. However, some simple choices before and after vaccination can affect how your body absorbs the protection.

1. Don't use sedatives right away

One of the most common mistakes is the rapid use of painkillers. Studies show that anti-inflammatory drugs, such as ibuprofen, can weaken the immune response by blocking the inflammation needed to create protective antibodies.

Although paracetamol is considered safe to relieve mild side effects – such as a sore arm or a low fever – doctors warn against taking it before the vaccine. Some studies suggest that using it beforehand may reduce the effectiveness of the vaccine.

Excessive use of paracetamol also carries risks: a large study of more than half a million people over 65 showed that regular use increases the likelihood of stomach ulcers, heart failure and kidney disease.

Even infrequent use – twice in six months – was associated with a higher risk of stomach bleeding.

Professor Zhang, the study leader, advised:

"Take it only when necessary, do not use it every day at the maximum dose, and be especially careful if you are over 65."

2. Avoid excessive alcohol

An occasional glass of wine is not expected to cause problems, but excessive drinking damages the immune system by affecting white blood cells, which fight infections.

This can cause more fatigue, muscle aches, and pain around the injection site, making you more susceptible to other infections.

Also, alcohol is a diuretic – it increases fluid loss through urine, which can lead to dehydration. Some studies suggest that this may slow down antibody production, making the vaccine less effective.

3. Do not do very heavy exercises immediately after the vaccine

Experts advise avoiding high-intensity workouts for 1–2 days after the vaccine, as they can increase fatigue and headaches.

However, moderate physical activity has positive effects. A 2022 study found that people who did a brisk walk, jog, or cycle for 90 minutes after getting a flu shot produced more antibodies against infections than those who didn't exercise — without any additional side effects.

The doctors' message is clear:

Do not use medications unnecessarily, especially before the vaccine; Avoid excessive alcohol and limit heavy physical activity in the first few days after vaccination.

These simple tips can make the difference in getting the most out of your flu vaccine. /GazetaExpress/