Traveling with Prescription pills

I've traveled with plastic box of pills for years, no issues.

This topic has been covered a lot recently - use search function “traveling with prescription drugs”. While never having been to Spain have traveled elsewhere in Europe and never had any queries about my medications. Have used both methods.

I have traveled to many places in Europe (including flying in and out of Madrid and Barcelona a few times each) using my Monday - Sunday pill container without any problems whatsoever. However, to be on the safe side, I do photograph the prescription bottle labels prior to my trip and store the photos on Google Keep on the very slim chance that I was questioned about it.

Haven't been to Spain but I don't see why your pill holder won't work. I put my prescriptions and OTC pills in tiny ziplock pills bags. I ask the pharmacist for duplicate labels and make a drug sheet which I carry in my paperwork file; also take a picture of it for quick access. The only drugs I keep in the original containers are antibiotics and a very old pain med prescription.

Spain's official tourism site says:

You can only carry the medicines you need, and they must be accompanied by a copy of the prescription or medical report.
https://www.spain.info/en/travel-tips/customs-regulations/#ancla-1

I spent two months in Spain last year and no one queried my medications, even the ones in the special travel cooler. Now, Heathrow was a very different story ...