The amount of wasted medicines thrown away in England in one year could fill 75 swimming pools, according to a pharmacy group.
The National Pharmacy Association (NPA) estimated that 3,400 tonnes of partly used medicines were disposed of in England in 2024-25.
The organisation, which analysed data from regional health bodies, also estimated that the problem costs the NHS at least £480m annually.
Olivier Picard, chair of the NPA, said: “Wasted medicines cost the NHS significant sums of money every year that could be invested in better services for patients.
“More than this, wasting medicines can have environmental and health consequences, and we can do much more to tackle this growing problem.
“As soon as a medicine leaves a pharmacy, even if it is not used and is unopened, it must be disposed of, so it is important patients only get medicines they are sure they will use.”
The NPA, which represents 6,000 independent community pharmacies in the UK, called for patients with several repeat prescriptions to have more reviews so that medicines that were no longer needed could be identified.
It also urged the public not to “over order” medicine.
Picard added: “We are urging patients only to request medicines if they really need them when ordering repeat prescriptions.
“As well as this, patients who are prescribed multiple medicines should have these more regularly reviewed to ensure they are being fully utilised.
“If a patient has any concerns about their medicines, they should speak to their pharmacist who can help them get the most out of their medicines.”
Dr Rasha Abdelsalam Elshenawy, a senior lecturer at the University of Hertfordshire, said surplus medicines “aren’t only a financial and environmental problem – it’s a patient safety and resistance problem”.
She added: “Leftover antibiotics kept at home are often taken later without medical advice, which fuels antimicrobial resistance, one of the biggest threats to modern medicine.
“Regular medication reviews and only ordering what is needed protects patients, the NHS and the environment.”
An NHS England spokesperson said it had taken action to ensure people could better manage their prescriptions on their mobile phones through the NHS app, including repeat prescriptions.
“We know there is more to do, which is why several local NHS services are running campaigns to reduce medicines waste, alongside wider efforts to optimise medicines use that have also seen the total number of dependency-forming medications prescribed fall over the last decade,” they added.
In June, health leaders warned that Britons were facing some of the “most severe” shortages of NHS medicines on record, including common painkillers, epilepsy drugs and HRT.
The NPA and the Royal College of GPs highlighted long-lasting supply issues affecting Estradot, a hormone replacement therapy (HRT) medicine used by menopausal women, and Creon, a drug taken by people with pancreatic cancer and cystic fibrosis to help them digest food.
