Straubing and Bogen have a system of 24 hour pharmacies that works quite well, if you know what you are looking for. All closed Apotheken, should have a sign that tells you which one is "on duty" for that night or weekend. They rotate responsibility for providing 24 hour coverage... rotating coverage a week at a time.
There is no extra charge for nighttime service. The cost of prescription medications is fixed in Germany, so you'll pay the same for a medication, no matter where you go. Some will not take credit cards, so be prepared. There can be a difference between the pharmacies and I hope to fill this information later. Many 'American' formulations are not typically stocked by the Apoteke's. This means they'll have to order them AND that they'll probably be more expensive than their German counterpart. You can save money and trouble by asking Pro-Spine if there is a similar German med that would be a more standard formulation. Some Apotheken are backed by large systems and a 'special order' med will appear, same day. Others may take a couple of days to get a non-standard med. Most of the pharmacies will deliver backordered meds to your hotel if it's not easy for you to come back. You'll love it if the local pharmacist shows up at your hotel with his kids in tow on the way home from work.
I hope this helps,
Mark
Photos below. Click any of the images to download a PDF version.
Note that this information was provided to Mark by Dr. Peter Holzner. He's the pharmacist for the hospital in Bogen and proprieter of Holzner Apotheke.