score:4
There are no DEA controlled substances.
Please check this for the UK and this for Ireland
The US Embassy in the UK states :
If you have a pre-existing condition, we recommend that you carry a letter from your physician listing the diagnosis and any medicine you take, including the generic names of prescribed drugs. Medications should be left in their original containers and clearly labelled.
The US Embassy in Ireland has an even more categorical wording :
Carry your prescription medication in original packaging with your doctorβs prescription. Also, carry a list of your medical history and all medications you are taking (including dosage and brand-name). Such lists will save Irish medical staff a lot of time, in the case that you are admitted to an Irish hospital during your vacation.
Leaving them in the original container is a near fool-proof way to be prevent being stopped/delayed at the border while they wonder what those pills are.