Can I have the flu jab if ...?

The flu jab is our best defence against flu which kills thousands of people in the UK each year. The NHS has a free flu vaccination programme for people aged over 65, children and other at-risk groups. People who aren't eligible for a free vaccination can still protect themselves by getting a private vaccination from their pharmacist, usually for less than £10.

There are only a few people who aren't able to get the vaccination at all. You can use the Patient Access flu eligibility checker to find out if you are able to get vaccinated and book your flu jab.

We spoke to specialty doctor and medical journalist Dr Patricia Macnair to answer some common questions about getting the flu jab.

Can I have the flu jab if ...

... I'm unwell?

"It depends on how unwell you are," explains Macnair. "If you just have a cold or sniffles then it's not a problem to have the flu vaccine. But if you have a fever or are more unwell then you should postpone your vaccination until you are better or your fever has settled."

The problem with getting a flu vaccine whilst you are unwell with more than a minor illness is that it makes it more difficult to tell if you have a bad reaction to the vaccine. It could also mean that you have a longer recovery time from your illness or that the vaccine ends up not being as effective because your body is already producing antibodies to fight your current infection.

If you are really unwell, it's worth seeking further advice before booking your flu vaccination.

"If you have a major illness requiring specialist treatment, you may want to check with your doctor first," says Macnair.

... I'm on antibiotics?

Usually taking antibiotics shouldn't prevent you from getting the flu vaccine, according to Macnair.

"However if you have just started the antibiotics and you are still feverish from the infection then you should postpone the vaccine," she says.

... I'm taking medication?

If you're taking other medication, you might be wondering if they might interact with the vaccine.

"There are a number of medicines which can affect the effectiveness of, or be affected by, the flu vaccine. These include steroids, phenytoin (for seizures) and drugs used for autoimmune disorders, as well as some over-the-counter treatments, vitamins and herbal products," says Macnair.

In addition, if you're taking the anticoagulant medicine warfarin, your INR blood test reading may be affected by the flu vaccine. For that reason, your pharmacist is likely to need to see your latest INR results (you should have a 'yellow book' in which your medical team writes down these readings every time you're tested) and check they're in the right range for you before they give your flu vaccine.

It's important to weigh up the risk of flu and an interaction, but whoever is giving you your vaccine should be able to advise you, she says. "In most cases the risk from a flu infection is far greater than the risk of an interaction but you should make sure you tell whoever is giving you the vaccine what medication you are taking."

... I'm pregnant?

Not only is it safe to have the flu jab during pregnancy but it is strongly advised. Pregnant women are more likely to develop a severe illness with flu and be admitted to hospital than non-pregnant women.

"Flu vaccination is recommended for pregnant women because it will protect both them and their unborn child," says Macnair. "In the later stages of pregnancy women are more vulnerable to developing complications if they do get flu."

And yet uptake of the vaccine among pregnant women is far lower than any doctor would like at only 47%, with many women not knowing that they're eligible for a free vaccination on the NHS.

"It is safe to have the usual flu vaccine, which doesn't contain any live virus, at any stage of pregnancy. The exception is the new form of flu vaccine given as a nasal spray to children," she explains. "This contains a live but inactivated virus and should not be used in pregnancy."

... I have an egg allergy?

Some flu vaccinations are made using eggs which can be dangerous to people who have an egg allergy as the vaccine may contain egg proteins, says Macnair.

This doesn’t always mean that people who have an allergy to eggs can’t have the vaccine.

"Some newer vaccines are not made with eggs and can be given to people with egg allergies. Make sure you tell the doctor or nurse giving you the flu vaccine that you are allergic to eggs. They can then give you a vaccine which does not contain egg proteins," she explains.

"If you have a severe egg allergy you may need to have the flu vaccine in hospital where any reaction can be quickly managed."

... I have an allergy to latex?

Some people have an allergy to latex which manifests as skin inflammation when their skin comes into contact with latex - so-called contact dermatitis. However, neither the vaccine nor any of the vaccine components that are in contact with the injection solution contain latex. That means that Public Health England has advised that people who are allergic to latex can have the vaccine.

A very small number of people have a very severe anaphylactic reaction when they come into contact with latex. Therefore, some pharmacists will advise people with this extreme form of latex allergy to contact their GP if they need a flu vaccination.

... I have a long-term health condition?

The free NHS flu vaccination programme covers a variety of long-term health conditions but uptake is still relatively low across the board. Even if you aren't eligible for a free vaccine, you can still get vaccinated privately at a pharmacy.

"Vaccination against flu is recommended for most people with long-term health conditions, such as asthma, heart disease or diabetes, especially among older people," says Macnair. "This is because these groups of people are more likely to develop serious complications such as pneumonia should they catch the flu."

Not every condition is covered by the free vaccination programme, and in some cases it might not be advisable to have a particular vaccine, she explains. "There are some conditions where the vaccine, especially the live attenuated type, may not be recommended, including those on high-dose steroids, being treated for cancer with chemotherapy or immunotherapy, or with unstable neurological conditions. Always check with your pharmacist or doctor first."

You can use the Patient Access flu eligibility checker to check whether you can get the flu vaccine. Get vaccinated to protect yourself and those around you this flu season.