Provided herein is an optimized method of enhancing endogenous gonadotropins and testosterone/estrogen production and concentrations comprising administration of a therapeutically effective amount of at least one GnRH agonist to a patient in need of such treatment. A method and dosing regimen is also described for delivery across the mucosa of the oral cavity for maximizing absorption and delivery, limiting systemic exposure and unwanted side effects, effectuating a sustained increase in concentrations of sex hormones and providing a non-invasive delivery that does not require inpatient visits. The method described benefits conditions such as hypogonadism in men due to aging or disease and symptoms related to menopause in women.
