Dexamethasone is commonly delivered via iontophoresis for which condition?

• A. Migraine
• B. Hyperpigmentation
• C. Asthma
• D. Tendonitis or bursitis

Answer: (D)

Iontophoresis uses an electrical current to push a charged drug through the skin into nearby tissues, so a corticosteroid that can be delivered in charged form is ideal for localized inflammatory problems. Dexamethasone is available as a phosphate salt that carries a charge, making it suitable for this method to reach superficial soft tissues. This approach is particularly helpful for tendonitis or bursitis, where targeted anti-inflammatory delivery to the affected area can reduce pain and swelling with less systemic exposure. The other conditions listed—migraine, hyperpigmentation, and asthma—do not rely on this skin-penetrating, localized anti-inflammatory treatment: migraines are treated with systemic or abortive therapies, hyperpigmentation with topical depigmenting agents or procedures, and asthma with inhaled or systemic corticosteroids, not topical iontophoresis.