Treatment for coughs, colds and the flu will look a little different in future after all medicines containing pholcodine were pulled from shelves.

But why were the medicines withdrawn - and what even is pholcodine?

Here's everything you need to know.

Why have some cough, cold and flu medicines been pulled?

The medicines have been withdrawn as a precaution following concerns over very rare cases of allergic reaction.

There is a "very rare" chance of people experiencing these allergic reactions when pholcodine is combined with general anaesthetic.

The Medicines and Healthcare Products Regulatory Agency (MHRA) conducted a review and took advice from the independent advisory body, the Commission on Human Medicines (CHM).

The conclusion of the review was that pholcodine-containing medicines are being withdrawn from the UK market "as a precaution".

What is pholcodine?

Pholcodine is used to treat dry coughs.

It is an opioid-based ingredient that has been used since the 1950s.

It works in the brain, suppressing the cough reflex by reducing the nerve signals that are sent to the muscles involved in coughing.

What happens when it's combined with general anaesthetic?

Neuromuscular blocking agents (NMBAs) are often used when someone is put under general anaesthetic to relax the muscles.

Taking pholcodine up to 12 months before undergoing general anaesthetic with NMBAs increases the chances of it causing a severe allergic reaction (anaphylaxis).

Scientists say this is because the antibodies from the pholcodine can stay in the body for a year - and will fight the NMBAs - as they are of a similar structure to the pholcodine.

This severe allergic reaction can result in brain damage or death.

However, the risk to patients who have taken pholcodine is "very small", the government's recall notice said.

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What should you do if you've taken a medicine containing pholcodine?

Taking one of these medicines doesn't mean you're immediately at risk of something bad happening.

Check your cough medicines to see if pholcodine is a listed ingredient.

If it is and you have questions, talk to a pharmacist who will be able to recommend an alternative treatment.

If you are due to undergo surgery with general anaesthetic and have taken medicines containing pholcodine - particularly in the previous 12 months - tell your anaesthetist.

The medicines being recalled include:

• Boots Night Cough Relief Oral Solution

• Boots Dry Cough Syrup 6 Years+

• Boots Day Cold & Flu Relief Oral Solution

• Cofsed Linctus

• Care Pholcodine 5mg/5ml Oral Solution Sugar Free

• Galenphol Linctus

• Galenphol Paediatric Linctus

• Galenphol Strong Linctus

• Covonia Dry Cough Sugar Free Formula

• Pholcodine Linctus Bells Healthcare 5mg Per 5ml Oral Solution

• Numark Pholcodine 5mg per 5ml Oral Solution

• Well Pharmaceuticals Pholcodine 5mg per 5ml Oral Solution

• Superdrug Pholcodine Linctus BP

• Strong Pholcodine Linctus BP

• Pholcodine Linctus BP

• Strong Pholcodine Linctus BP

• Pholcodine Linctus

• Day and Night Nurse Capsules

• Day Nurse Capsules

• Day Nurse