Bromocriptine Mesylate for Glycemic Management in Type 2 Diabetes Mellitus

Abstract

Objective: To review the pharmacologic characteristics, safety, and efficacy of bromocriptine mesylate for glycemic control in patients with type 2 diabetes mellitus. Data Sources: A Scopus and MEDLINE search (1950–June 2010) was conducted using the key words bromocriptine, diabetes, and circadian rhythm. Data were also received from the manufacturer. Study Selection and Data Extraction: Available abstracts, studies, and review articles published in English with human data discussing bromocriptine treatment for type 2 diabetes mellitus were reviewed. Data Synthesis: Bromocriptine is an ergot derivative available for treatment of type 2 diabetes. The mechanism of action of this agent is unclear; however, activity as a dopamine D2 receptor agonist seems to provide the primary mechanism for utility in resetting the circadian rhythm in patients with type 2 diabetes. Other mechanisms, including α-1 antagonist, α-2 agonist, and serotonin and prolactin modulator, may also help to explain bromocriptine's glucose-lowering effects. Studies with bromocriptine have included 4328 patients with type 2 diabetes. The majority of available trials conducted enrolled patients for a study duration of 6–24 weeks. One trial evaluating the safety and efficacy of bromocriptine concluded after 52 weeks of follow-up. Endpoints of hemoglobin A1c (A1C) reduction and plasma glucose concentrations were the primary focus of all studies, with statistically significant differences found. Bromocriptine use resulted in a mean A1C reduction of 0.27% (range 0.1–0.6), while placebo resulted in a mean A1C increase of 0.48% (range 0.3–1.1), Incidence of adverse effects of nausea, vomiting, headache, and rhinitis was greater than that of placebo in clinical trials. Cardiovascular endpoints did not differ from those of placebo. Conclusions: Bromocriptine has demonstrated efficacy as an adjunctive agent in the management of type 2 diabetes. Caution may be warranted in the elderly population or patients at risk for suspected drug-drug interactions. Further studies of longer duration may help to define the role of bromocriptine in the management of diabetes.