IME I've never had a problem mixing either Melafix or Pimafix with a actual med.
I wouldn't hesitate to add either or both of these in with a med.
When I use Mela/Pimafix, I use'em together.
I too wouldn't ever mix actual medicines without 100% knowledge of compatibility.
I only use/recommend meds as a last resort, I much prefer a natural solution if possible.
Water quality, heat, salt, natural remedies, stress reduction and etc...