Antibiotics have been called the most important step in medical history, and since penicillin was discovered in 1928, the drugs have saved millions of lives.

[Read more: 7 things you should always have in your medicine cabinet]

We’re always told it’s vital to complete antibiotic courses to make sure the infection has been completely eradicated – but now a group of senior scientists have said there’s no evidence to support this.

Instead, they suggest just taking antibiotics till you feel better might be “safe and effective”, and help reduce the growing bacterial resistance which is threatening the effectiveness of antibiotics.

However, the Royal College of General Practitioners (RCGP) insists the current approach to antibiotics shouldn’t change because of just one study, and is urging patients to carry on taking their full antibiotic courses.
Confused? Here are the facts:

What do antibiotics do?

Antibiotics either kill bacteria by interfering with the formation of the bacterium's cell wall or its cell contents, or they stop bacteria from multiplying. They can only treat infections caused by bacteria, and aren’t effective against viruses, such as colds and flu.

Why are bacteria becoming resistant to antibiotics?

Some bacterial resistance is thought to stem from the overuse of antibiotics, because when someone takes antibiotics, sensitive bacteria are killed but resistant bacteria are left to grow and multiply. Consequently, repeated use of antibiotics increases the number of drug-resistant bacteria.

In a bid to slow down the increase in resistant bacteria, doctors have been trying to reduce the unnecessary use of antibiotics, for instance, by not prescribing them for viruses. But patients who are prescribed antibiotics are always told it’s important to complete the whole course to prevent the infection returning.

[Read more: Here's the scary situation we'll face when antibiotics stop working]

No evidence to support course completion

However, a new report in the British Medical Journal by 10 senior scientists says that after scouring relevant medical literature, they found no studies to support the ‘complete the course’ doctrine. Therefore, they suggest it could be better for patients to stop taking antibiotics as soon as they feel better, as this may help reduce antibiotic resistance in bacteria. The report says: “There is evidence that in many situations stopping antibiotics sooner is a safe and effective way to reduce antibiotic overuse.”

Don’t stop yet

But Professor Helen Stokes-Lampard, chair of the RCGP, insists the public shouldn’t change the way they take antibiotics on the back of just one study.

“Resistance to antibiotics is one of the biggest health challenges we face globally,” she says. “It’s important that we take new evidence around how to curb this on board, but we cannot advocate widespread behaviour change on the results of just one study.”
She points out that recommended courses of antibiotics aren’t random, but are tailored to individual conditions and in many cases, are quite short. For urinary tract infections, for example, three days is often enough to cure the infection.

Stokes-Lampard says that while more research on antibiotic courses is clearly needed, guidelines will not be changed unless there’s more good evidence to do so. “We’re not at that stage yet,” she stresses.

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Always take the full course

“We are concerned about the concept of patients stopping taking their medication mid-way through a course once they ‘feel better’, because improvement in symptoms does not necessarily mean the infection has been completely eradicated.

“It’s important that patients have clear messages and the mantra to always take the full course of antibiotics is well known – changing this will simply confuse people.

“GPs are playing a huge part in curbing the trend for overuse of antibiotics, and will prescribe in accordance with clinical guidelines, and act in the best interests of the patient.

“We would urge our patients not to change their behaviour based on one study.”