Martin Lewis encouraged viewers of his ITV show to search for a specific code when comparing different tablets to see if they can get the same product for less. He mentioned the tip as the cost of an NHS prescription in England is increasing from £9.35 to £9.65 next month which could mean a big increase in costs for those on regular medication.
Over-the-counter medicine packaging should have a product licence (PL) code unique to that particular item, rather than the active ingredient in the medicine.
This means if two different products have the same code, they are exactly the same product but prices can vary for different brands.
To illustrate this, Mr Lewis compared two packets of tablets for period pain. They both had the same PL code but one packet cost £5.29 while the other cost just £3.45.
He said: “Exactly the same tablets. Same product licence, same tablets, totally different price. Just for the packaging.”
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He told viewers they can also make big savings when buying tablets by looking for the active ingredient in medicine.
For example, in Nurofen the active ingredient is ibuprofen, and there are other tablets containing ibuprofen which are much cheaper.
People should be aware different brands may use different coating for the tablets so a person should check they are not allergic to any of the ingredients.
Some people can get NHS prescriptions for free including those aged 60 or over, or those aged under 16, or aged 16 to 18 and in full-time education.
The cost of the certificates is also increasing in April with a three-month certificate costing £31.25 while a 12-month certificate will cost £111.60.
All people in Scotland and Wales can get free NHS prescriptions regardless of their situation.
Many other bills are also increasing in April, including water bills, broadband and mobile tariffs and council tax.
The Martin Lewis Money Show returns tomorrow for a Budget special at 8.30pm.