Compositions, formulations, methods, and systems for treating regional fat deposits comprise contacting a targeted fat deposit with a composition comprising long acting beta-2 adrenergic receptor agonist and a compound that reduces desensitization of the target tissue to the long acting beta-2 adrenergic receptor agonist, for example, glucocorticosteroids and/or ketotifen. Embodiments of the composition are administered, for example, by injection, and/or transdermally.