A transdermal patch comprising (2R,6R)-hydroxynorketamine or a conjugate thereof. The active agent may be in its free base form. The transdermal patch may comprise a drug-containing layer comprising the active agent and a carrier material. The transdermal patch may comprise an adhesive. Examples of adhesive materials that could be used include pressure-sensitive acrylic adhesives, pressure-sensitive silicone adhesives, or other type of pressure-sensitive adhesive.
