Formulation and pharmacological studies of a controlled release pentagastrin injection

Abstract

Four formulations were designed to release pentagastrin at different rates after subcutaneous injection. These formulations were tested in vitro for rate of diffusion across a dialysis membrane into pH 7·3 phosphate buffer, and in vivo in rats for rate of excretion in the bile and on dogs for pharmacological responses. Good agreement was observed between the in vitro data, elimination rate and dose response data for the rate of release and duration of action of the four formulations. The results agreed with the theory that by controlling the rate of release of a short acting drug, one could sustain the pharmacological response to the drug and increase the total response by better utilization of an administered dose.