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How long do antibiotics take to work?

ANTIBIOTICS are usually something you'll come across if you suffer a nasty bug.

The life-saving pills are used by millions every year, for a whole host of issues.

Millions of people are prescribed antibiotics every year and here we discuss how long the drugs take to work
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Millions of people are prescribed antibiotics every year and here we discuss how long the drugs take to workCredit: Getty

They are specifically used to help our bodies fight off bacterial infections.

And once upon a time, they were handed out relatively freely.

But since, many countries have joined the fight to prevent antibiotic resistance, the drugs are no longer routinely used to treat all infections.

At the end of last year pharmacists faced shortages of several antibiotics as soaring Strep A cases lead to a huge increase in demand for the drugs at the end of last year.

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Antibiotics don't work for everything and here we take a look at how long it takes them to work and whether or not you need to take the full course.

How long does it take for antibiotics to start working?

Antibiotics start to work straight away — but you might not get them until you felt unwell for a while.

They work by or preventing bacteria from spreading or killing them, the NHS states.

However, they don't work for viral infections.

This includes colds and flu, Covid, chest infections, ear infections in children, and most coughs and sore throats.

In most cases they will be prescribed to you if the bacterial infection won't clear up without them or if you could infect others.

Medication could also be given if the infection would take too long to clear on its own or if it carries the risk of more serious complications.

When will I feel better and are there any side effects?

Everyone is different - as is there response to antibiotics.

Most people will feel better towards the end of the course, but this varies.

"It depends on the infection and antibiotic being taken," Mike Hewitson, a pharmacist from Bristol says.

"Remember that even if you feel better from the infection the antibiotics may make you feel unwell.

"Antibiotics can make you feel nauseous or give you an upset stomach," he adds.

If you have completed the course and don't see any signs of improvement, talk to your doctor or pharmacist.

According to Mike Hewitson, a pharmacist from Bristol, antibiotics get to work immediately, but you might not start to feel better straight away.

Mike says: "How quickly you begin to work depends what antibiotic you are on, the strength of it and what infection you are treating.

"If you're receiving them through an IV they can begin to work within hours.

"But some oral antibiotics can take a week or so to take effect."

Most antibiotics should be taken for one to two weeks but shorter treatments work just as well in some cases.

Your doctor will decide the best length of treatment and correct antibiotic type for you.

Do I need to take my full course of antibiotics?

It can be tempting to stop taking antibiotics as soon as you're starting to feel better - but doctors say you shouldn't.

Mike says: "It's very important to finish your course of antibiotics, even if you're no longer feeling infectious and you feel better.

"Not finishing the course may result in the infection returning."

Doing so also contributes to the growing issue of antibiotic resistance

Do not stop your antibiotics early without first talking with your doctor.

If you forget to take an antibiotic, it's not the end of the world, but take that dose as soon as you remember and carry on with the course of antibiotics as normal.

But if it's almost time for the next dose, skip the missed one and continue your regular dosing schedule.

Do not take a double dose to make up for a missed one as this can increase the risk of side effects.

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When it comes to side effects of the medication, the NHS states that the most commonly, people will feel sick, be sick, have bloating and indigestion, with others also have diarrhoea.

Guidance states that some people might also have an allergic reaction to the medication - especially penicillin and another type of antibiotic called cephalosporins.

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