Healthcare consultancy Medicom Group is handling the comms activity behind a report launched by the European Alliance for Access to Safe Medicines (EAASM) last week.
The report, which questioned 100 online pharmacies, revealed that 62 per cent of medicines purchased online are 'fake or sub-standard'.
These include medicines claiming to treat serious conditions such as cardiovascular and respiratory disease, neurological disorders and mental health conditions.
The report found that more than 90 per cent of commonly purchased prescription-only medicines were being ordered online.
All medicines were delivered without requiring sight of the prescription, which is illegal.
'The industry has to strike a balance between responsibly informing patients that counterfeit drugs exist and not overly worrying them to the point that they don't take their medicines,' said Medicom chairman Martin Ellis.
Almost all (96 per cent) of online pharmacies researched operate illegally and 94 per cent do not have a named, verifiable pharmacist. The report found that there is a three in five chance of receiving a fake or substandard medicine when you buy online.
EAASM chair Jim Thomson commented: 'The report findings are shocking and the problem is set to become even bigger than it is now.
'We need support from the pharma industry and other stakeholders to take action and halt this dangerous trend.'