Which compound is NOT listed as an analgesic or anti-inflammatory used for iontophoresis?

• A. Dexamethasone
• B. Lidocaine
• C. Salicylate
• D. Acetaminophen

Answer: (D)

Iontophoresis works best when the drug can carry a charge and move through the skin under an electric field. Dexamethasone and salicylate are commonly used for their anti-inflammatory effects because they exist as charged ions in solution, making them effective for iontophoretic delivery. Lidocaine is used for its local anesthetic action and also relies on a charged form to migrate through the skin. Acetaminophen, while an analgesic, does not provide significant anti-inflammatory effect and does not ionize well enough for reliable iontophoretic delivery, so it isn’t listed as an analgesic or anti-inflammatory used for this method.