A no-deal Brexit could see prescription strengths decrease and “alternative” remedies handed out in Scotland.
And patients have been urged not to stockpile medicine.
The warning came from Scotland’s top medical official Dr Catherine Calderwood as Britain moved closer to crashing out of the EU without a trading agreement.
Calderwood said: “Shortages may occur but the NHS will manage the situation and, if necessary, provide suitable alternatives or other treatment while supply is restored to normal levels.”
The advice was set out in a letter published by the Scottish Government.
Calderwood and chief pharmaceutical officer Dr Rose Marie Parr said a no-deal exit risks “more shortages than are normally experienced”.
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The advice added: “Where more serious shortages of medicines occur, individual ‘serious shortage protocols’ may be developed and clinically authorised which will enable pharmacists to amend prescriptions to dispense a different strength, formulation or an alternative medicine, within the scope of the protocol.”
Medicines not already part of a six-week stockpile are kept under review.
The letter added: “The Scottish Government is working with all other UK administrations to make sure that people receive the medicines and other medical supplies they need, as far as is possible, if the UK leaves the EU without a deal.
“Pharmaceutical companies have stockpiled medicines and across the UK the NHS has stockpiled other supplies like medical devices and clinical consumables.
“Arrangements are also being made to transport into the UK, including by air, items that cannot be stockpiled.
“The UK Government has stated that, if there are delays at the UK border, medical supplies will be given priority for entry into the UK.
“Members of the public, GPs, community pharmacies and hospitals should not stockpile.”
Scottish Lib Dem health spokesman Alex Cole-Hamilton said: “Any Brexit will be bad for our NHS, whether it be by crashing out without a deal or cutting off the precious supply of European workers who support patients in our health service.”
