Not really sure, but maybe you could call your pharmacist. I know how it is to call the dr. office, but my pharmacy is really good to talk to me right away. Maybe yours will be too. Just a suggestion. Good luck and I hope you get your answer soon.
I can't think of any solid reason why you should be taking the Toprol and Altace at different times if it is inconvenient for you (well, other than the fact that your doctor told you you shouldn't).
Post-marketing studies were done on Altace to see if people taking Altace and extended release propranolol had any increased risk of side-effects (propranolol is a beta-blocker similar to Toprol but with more beta-blocking capacity). The results showed that there is no increased risk of side-effects if you take both Altace and propranolol at the same time. I don't see why this would be any different for Toprol--it should be just as safe.
The only thing I can think of is that your doctor may want to minimize any sudden drop in your blood pressure by taking two antihypertensives at once. Since you are artificially inducing low blood pressure to control your hypertension, your body has to adjust each day when you take the medication. Taking each medication an hour apart may allow each to begin having an effect and give your body time to adjust without effects from the other drug. However, I find this highly unlikely since people often take multiple antihypertensives in the same dose without any trouble.
Point being...without any reasoning from your doctor, you should be fine taking both medications at the same time. If you want more information about each medication, visit www.rxlist.com. There you can find out about the side-effects and what drug interactions exist for Altace and Toprol XL.
Thank you!! My thoughts exactly! And thanks for the website, very informative.