Descriptive analysis of reported adverse events associated with anti-obesity medications using FDA Adverse Event Reporting System (FAERS) databases 2013-2020

Int J Clin Pharm. 2022 Feb;44(1):172-179. doi: 10.1007/s11096-021-01330-2. Epub 2021 Sep 26.


Background Obesity is a globally growing health problem, and its treatment has been challenging. The use of anti-obesity medications (AOMs) has been associated with severe adverse events (AEs). Several AOMs have been withdrawn from the market owing to documented AEs. Aim To describe, estimate and characterize the frequency of AEs attributable to the use of the AOMs, and investigate previously unreported potential AEs associated with AOMs. Method Using the US FDA Adverse Event Reporting System (FAERS) between January 2013 and June 2020, a retrospective, descriptive analysis was conducted to analyze all major reported AEs and outcomes including death, life-threatening, hospitalization, disability, and required intervention or congenital anomaly. The total numbers of AEs reports, cases, adverse reactions and outcomes were calculated for each medication. Results A total of 18,675 unique AEs reports associated with AOMs used for 15,143 patients. The mean age was 49.8 years [SD 1.83], while most patients were female adults (73.4%). The most frequently reported AEs were nausea and vomiting, followed by dizziness and headache, drug ineffectiveness, cardiovascular diseases, and kidney complications. There were 21,229 unique outcomes, including 1039 deaths (fatality ratio of 4.9% of all analyzed reports), 1613 (7.6%) life-threatening events, 7426 (35%) hospitalizations, and 1249 (5.9%) disability cases. Phentermine/topiramate fatal cases represent 6% of the overall medication's reported AEs. Cardiovascular AEs represented 31%, 23%, and 22% of phentermine, liraglutide, and phentermine/topiramate total AEs, respectively. Conclusion The analysis of FAERS database revealed numerous serious AEs associated with AOMs. These AEs can lead to serious cardiovascular and kidney complications. It is necessary to continue and systematically monitor safety of AOMs' to optimize patient anti-obesity therapy.

Keywords: Adverse events; Adverse reactions; Anti-obesity medications; Cardiovascular disease; Drug safety; Drug utilization; FDA Adverse Events Reporting System; Obesity.

MeSH terms

  • Adult
  • Adverse Drug Reaction Reporting Systems
  • Anti-Obesity Agents* / adverse effects
  • Databases, Factual
  • Drug-Related Side Effects and Adverse Reactions* / diagnosis
  • Drug-Related Side Effects and Adverse Reactions* / epidemiology
  • Female
  • Humans
  • Middle Aged
  • Obesity / drug therapy
  • Obesity / epidemiology
  • Retrospective Studies
  • United States / epidemiology
  • United States Food and Drug Administration


  • Anti-Obesity Agents