Formulations for oral transmucosal compositions including a synergistic combination of low doses of testosterone with an aromatase inhibitor (AI) that are combined with transmucosal absorption enhancers are disclosed. Oral transmucosal compositions can be for fast release or slow release, and can be administered to increase bloodstream testosterone levels and thereby reduce symptoms of testosterone deficiency. Oral transmucosal compositions include liquid dosage forms, solid dosage forms, and chewing gums. Further dosage forms include mucoadhesive thin strips, thin films, tablets, patches, and tapes, among others. Other dosage forms are: mucoadhesive liquids such as gel-forming liquids; gel-forming semisolids; and gel-forming powders, among other dosage forms that exhibit mucoadhesive properties, and provide oral transmucosal delivery of testosterone and AI. Oral transmucosal compositions will deliver testosterone and AI directly into the patient's bloodstream, and provide high bioavailability of testosterone and AI; therefore, the required doses are lower.