That doctor sounds like he might not know what he's doing. He switched your husband FROM amlodipine becasue it caused swollen ankles (it does for a LOT of people) and he switched him to amlodipine plus benazepril.
The amlodipine STILL is causing the swillen ankles.
Is it possible his doctor doesn't KNOW he's prescribing the same drug? If so, he should look for a different line of work.
If your husband is showing ankle swelling he should STOP taking Lotrel, Norcasc or amlodipine...all the same thing. This same problem is occurring all over his body; it is just most noticeable in the ankles.