A Fresh Look at Iontophoresis

The rate of penetration of fluorescein and gentamicin ions into the anterior chamber of the rabbit was increased more than 100-fold by the passage of 1 mamp; the amount of drug that penetrates is better controlled by iontophoresis than by instillation. The potential value, the safety and the limitations of this procedure are discussed, and a theoretical basis for the increase is provided. Practical methods of using iontophoresis in the clinic are described. A 30-s application should result in a therapeutic level of the antibiotic in the anterior segment over a 12-hour period in eyes with an intact epithelium.