Humans also take metro (it is a prescription only med) but it won't be at the same dosage. I would get the Seachem dosage (can be another brand at same or similar dosage) to mix into meds just because I know you won't over medicate and hurt your fish. I don't have experience with other potency. I'm also not completely sure if there may be any difference between what people take and what you can mix into your aquarium, although I think it's the same thing. You can mix General Cure by API into a med too. It's metro and prazi in a packet.
Okay, this is just a quick question about the Metro. Does it have to be specifically for pets/fish? My dad and mom works at the hospital so I think we have some. Does it even need a prescription? I don't know. lol