A method for improving the ultrasonic transdermal delivery of an drug by modifying the excipient solution to which an active ingredient is intermixed in a drug formulation, whereby the choice of excipient solution is modified to one which will be more conducive to ultrasound and will propagate the drug substance at a higher delivery speed through the skin under ultrasonic excitation An example of such an excipient change includes a conversion from a standard dibasic sodium phosphate containing formulation to one using far less sodium or less preservative compositions. Reduced dibasic sodium phosphate formulation. Responsively to insonification thereof, including: reducing the amount of dibasic sodium phosphate in the formulation to provide a reduced dibasic sodium phosphate formulation and, making a substance in accordance with the reduced dibasic sodium phosphate formulation.