Phono means sound and phoresis means migration of the ions through a membrane by the action of an electric current.
Phonophoresis is defined as the movement of the drugs through skin into the subcutaneous tissues under the influence of ultrasound.

Phonophoresis depends upon:

·         Intensity of ultrasound
·         Frequency of ultrasound
·         Nature of drugs
In 1950s, they said that the drugs goes 4 – 5 cm deep to the skin while recent study shows that drugs go 1 -2 mm deep into the skin.


·         Bursitis
·         Tendinitis
·         Medical interest of transcutaneous systemic delivery of substances such as insulin that cannot be delivered effectively by mouth
·         For superficial effects, cutaneous anaesthetic are delivered by frequency devices