Phonophoresis is described as?

• A. Use of ultrasound waves to introduce medication across the skin into subcutaneous tissues
• B. A surgical technique to implant drug reservoirs
• C. A heat therapy technique
• D. An electrical stimulation method

Answer: (A)

Phonophoresis uses ultrasound energy to push a topically applied medication through the skin into deeper tissues. The ultrasound temporarily increases skin permeability through mechanical effects like cavitation and acoustic streaming, sometimes with mild heating, enabling the drug to reach subcutaneous tissues more effectively. This approach is used in physical therapy to enhance local anti-inflammatory or analgesic effects without injections. It isn’t a surgical technique, nor is it primarily a heat therapy or an electrical stimulation method (which would be iontophoresis).