i.            Iontophoresis uses electric current to transport ions into tissues through skin while Phonophoresis uses acoustic energy (ultrasound) to drive molecules into the tissue through skin.
       ii.            Iontophoresis has immediate effect while Phonophoresis has prolong effect
      iii.            The treatment time for Iontophoresis is 15 – 20 min while that for Phonophoresis is 5 -10 min.
     iv.            Iontophoresis is done through electrode while Phonophoresis is through probe (transducer head)
       v.            In Iontophoresis there are chances of chemical burn while Phonophoresis is safe.
     vi.            Iontophoresis is painful while Phonophoresis is painless.
    vii.            Iontophoresis is difficult method while Phonophoresis is simple method