D-aspartic acid is prepared as its hydrochloride salt or as the hydrochloride salt of its diethyl ester, thereby providing soluble forms of D-aspartic acid that are readily taken up by a human body via its digestive tract. The D-aspartic acid is administered as pills, capsules, powdered drink mixes, beverages, confectionaries, syrups, chewable tablets, nasal sprays, or injectable formulations.
