Around 139,963 prescriptions are dispensed on-Island each month
The former health minister says there is no data held on how many UK prescriptions have been dispensed on the Isle of Man.
Lawrie Hooper was asked how many have gone through Island pharmacists in each of the last five years by Onchan MHK Julie Edge.
He gave his answer before he resigned in Tynwald this week.
Mr Hooper revealed that each month, around 139,963 prescriptions are dispensed on-Island at an approximate net cost of £1.35 million to Manx Care.
These include GP, dental and hospital outpatient prescriptions.
Ms Edge asked if his department would commit to looking into what she deemed 'prescription holidaymakers' who may wish to redeem UK prescriptions here where the charge is lower.
But Mr Hooper said that was not possible under the recently extended reciprocal health agreement:
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