Approximately 139,963 prescriptions are filled on the island each month.
The former health minister said no data was kept on how many British prescriptions were dispensed on the Isle of Man.
Laurie Hooper was asked by Onchan MHK Julie Edge how many pharmacists she had worked with on the island in the past five years.
He gave his answer before resigning in Tynwald this week.
Mr Hooper revealed that approximately 139,963 prescriptions are dispensed on the island each month, with a net cost to Manx Care of approximately £1.35 million.
These include outpatient prescriptions from GPs, dentists and hospitals.
Ms Edge asked whether his department would commit to investigating people she identified as “prescription holidaymakers” who may wish to redeem cheaper UK prescriptions here. .
But Mr Hooper said that would not be possible under the recently extended reciprocal health agreement.
