Although shortages have been reported for a number of medicines, figures show that manufacturers are providing ‘more than enough' stock of these products, the association said.
However, data suggest that 11% of the UK's 12,600 pharmacies are exporting medicines intended for the UK market, along with a ‘tiny number' of dispensing doctors, the ABPI said.
A wide range of drugs have been affected by supply problems. They include insulin, asthma treatments and oral contraceptives, as well as immunosuppressants, cardiovascular drugs and psychological therapies for conditions such as depression, epilepsy and attention deficit hyperactivity disorder.
Prescription drugs tend to be cheaper in the UK than elsewhere in Europe. This pricing discrepancy and the weak pound has created an incentive for wholesalers, pharmacists and dispensing doctors to order extra stock and sell medicines overseas for profit.
David Baker, chief executive of the Dispensing Doctors' Association, said that any dispensing doctors carrying out such trade, known as parallel exporting, should stop doing so.
‘Our advice is that you really shouldn't be doing this,' he said. ‘It is legal, but it is ethically questionable.'
Dr Baker said he would like the government to take action to ensure that medicines intended for UK patients could only be exported once the home market need had been met.