Which option correctly pairs iontophoresis medications with their polarity and purpose?

• A. DEX (-) inflammation; Lido (+) pain; Saline (-) scars; Acetic Acid (-) calcifications
• B. Lido (-) pain; DEX (+) inflammation; Saline (+) scars; Acetic Acid (+) calcifications
• C. DEX (+) inflammation; Lido (-) pain; Saline (-) calcifications; Acetic Acid (-) scars
• D. DEX (-) pain; Lido (+) inflammation; Saline (-) calcifications; Acetic Acid (+) scars

Answer: (A)

In iontophoresis, you move charged medications through the skin by using an electric field, so the drug’s charge must match the electrode you place it under and the therapeutic effect comes from delivering that charged drug to the target tissue.

Dexamethasone is used for inflammation and, in iontophoresis, is typically supplied in a negatively charged form. Placing it under the negative electrode drives it into the tissue to reduce inflammation.

Lidocaine is a positively charged local anesthetic, so it’s placed under the positive electrode to deliver pain relief at the treated area.

Acetic acid is used to address calcium deposits because it forms acetate (a negative ion) and is delivered with the negative electrode to help dissolve calcifications.

Saline serves as an electrolyte vehicle rather than a targeted drug, and when used in this context it’s about facilitating conduction and tissue hydration rather than delivering a specific pharmacologic action.