I take the toprol xl and I use the generic and it cost me roughly $20 and I take 125mg twice a day. but you must make sure it is the generic for toprol xl because there is metoprolol succinate which is the generic for toprol xl and metoprolol tartrate which is the generic for lopressor. They both work in two different ways so they can not be interchanged at the same dose. I asked this question before toprol xl became a generic. Hope this helps :)
Toprol XL is metoprolol succinate and is an extended release prescription...the immediate release is metoprolol tartrate. If he was prescribed 100 mg Toprol XL once/day it should be the same as taking metoprolol tartrate 50 mg 2/day. We are not physicians nor pharmacists and you should consult one or both about drug substitutions and dosage equivalents.