Martin Lewis has shared a tip that could help people potentially save a bit of money when buying over-the-counter medicines in England.

On the Martin Lewis Money Show yesterday (Tuesday, March 14), he revealed a "simple" check people should make before buying a certain product.

He shared that there is a "secret" nine-digit code, known as the Product Licence code, which is printed on the box of every product. 

By using this code, viewers could identify cheaper off-brand alternatives to big-name brands, The Mirror reported.

Speaking on the show Martin said: "I have in front of me two packets that were bought today. They are both for period pains - painkillers.

The Argus: In some cases the exact same tablets can cost differently based on what the packaging branding isIn some cases the exact same tablets can cost differently based on what the packaging branding is (Image: PA)

"This one cost £5.29, this is £3.45. But if you look on the side of these boxes, the PL Code, the Product Licence code. 12063/0071. And 12063/0071.

"That doesn't mean same active ingredient. That means these are exactly the same tablets."

He suggested that in many cases, people are "paying for the packaging" with big-name brands, and therefore it would be beneficial to do a bit of research and compare prices using the Product Licence code.

Further Martin Lewis advice on saving money when buying medicine

The Money Saving Expert also advised people to check the code even if there's not an identical medicine that's cheaper.

This is because it can often be possible to save cash by turning away from branded products and opting for an unbranded or own-brand equivalent.

Martin said it was the medicine's "active ingredient" that mattered and the rest is largely irrelevant unless you have certain allergies.

He explained: "If you're buying Nurofen the active ingredient in it is ibuprofen and you can buy generic ibuprofen for far less than Nurofen, it does the same thing."

"The only thing you have to watch for is whether it's coated, or what the ingredients are if you've got an allergy or something like that and maybe the speed of operation. But the active underlying ingredient is the same."