'Black box' explained as Covid vaccine 'to get FDA’s strongest warning'

The US is reportedly looking at applying a 'black box' warning to vaccines for Covid-19 – but what does that mean exactly?

Manufactured during the height of the pandemic, the Covid vaccine - often referred to by brand names such as Pfizer, AstraZeneca and Moderna - played a huge role in combating the respiratory virus and allowing nations to let their citizens out of lockdown.

However, not everyone was convinced to take the shot, with a growing 'anti-vax' movement seeing numerous people refuse the vaccine amid a growing mistrust in modern medicine.

And recent news is likely to cause more anxiety, as the US Food and Drug Administration is weighing up adding a black box label to the drug, according to a report from CNN.

But what exactly is a black box or boxed warning?

Opinions on the safety of the Covid vaccine differ greatly (Getty Stock Images)

What does a 'black box' or boxed warning mean?

According to an explainer from a pharmacologist in The Conversation, drugs receive a boxed warning when they are considered to have side effects which can result in serious injury or death.

The warning is printed on package inserts for the medication and allows doctors to weigh up the benefits of prescribing the drug against the risk of possible side effects.

As of 2022, over 400 different medications had been given a boxed warning by the FDA. This includes drugs containing opioids (due to increased risk of addiction) and certain antidepressants (due to a risk of suicidal ideation when given to young people).

While the highest level of warning used for medications, this boxed warning does not mean a drug is banned from being used.

The decision to add this warning to Covid vaccines is yet to be confirmed, with a spokesperson for the US Department of Health and Human Services saying the reports were 'pure speculation', however an announcement is expected to be made at the end of the year.

The news also follows an update to guidelines on the Covid vaccine, which sees it no longer recommended to children and pregnant women in the US.

A 'black box' warning is considered the most serious safety warning for drugs (Getty Stock Images)

Why would this warning be applied to Covid-19 vaccines?

The reports follow a decision by the FDA to update prescription guidelines for Covid vaccinations, after a possible link between the drug and side effects myocarditis and pericarditis.

Conditions which cause inflammation of the heart's muscle (myocarditis) or wall (pericarditis), which can often occur after the body has fought off a viral infection.

In mild cases, the disease can resolve on its own, however more serious cases of myocarditis and pericarditis require medical attention.

When it comes to the Covid jab, the side effect is believed to be rare, with up to one in 10,000 people vaccinated affected by the illness.

Research found that you're more likely to develop myocarditis or pericarditis from catching Covid itself (Getty Stock Images)

Meanwhile, a recent study noted that patients are more likely to develop either myocarditis or pericarditis from catching Covid itself rather than the vaccine, while research published in the journal JAMA Network Open revealed that patients who've taken the vaccine have a 25 percent lower risk of all-cause mortality.

LADbible previously reached out to the US Department of Health and Human Services, as well as Pfizer and Moderna, for comment.