Belviq® and Belviq XR® - Williams Cedar LLC



There are over 70 million adults in the United States are classified as obese. Obesity is defined as having a BMI (Body Mass Index) over 30. BMI is calculated by dividing your weight in pounds by your inches in height squared and multiplying by a conversion factor of 703. The CDC hosts a BMI Calculator on their website to assess if you lie within a healthy weight range. They define a “Normal” range as any BMI between 18.5 and 24.9. A BMI below 18.5 is considered “Underweight” and a BMI from 25 to 29.9 is considered “Overweight”.

Belviq® and its Purpose

Belviq®  (lorcaserin) was approved by the FDA in June 2012 after first being rejected in September 2010 by an FDA advisory panel after concerns over testing in rats which showed tumor growth, and its weight loss efficacy was considered “marginal”.

The drug is used to help promote weight loss in patients with a BMI of over 30 (obese) or adults with a BMI of over 27 (overweight) who also had one weight-related condition such as hypertension (high blood pressure), type 2 diabetes or dyslipidemia (high cholesterol).

The drug works by activating 5-HT2C receptors in the hypothalamus, which activates proopiomelanocortin production, which promotes weight loss through satiety (the feeling of being full).

Side Effects and Serious Injuries

In May 2013, the DEA (US Drug Enforcement Agency)  classified Lorcaserin as a Schedule IV drug due to its hallucinogenic properties when taken in higher than approved doses which could cause patients to become psychiatrically dependent on the drug.

In January 2020, the US FDA (Food and Drug Administration) released a statement that a clinical trial showed a possible increase in instances of certain cancers for patients taking Belviq®. These cancers included Pancreatic Cancer,  Colorectal and Lung Cancer.

Less serious side effects include:

  • low blood sugar (hypoglycemia)
  • mental problems
  • slow heartbeat
  • headache
  • dizziness
  • drowsiness
  • feeling tired
  • fatigue
  • nausea
  • dry mouth
  • cough
  • back pain
  • constipation
  • painful erections
  • diarrhea
  • vomiting
  • upper respiratory tract infection
  • runny or stuffy nose
  • urinary tract infection
  • muscle pain
  • sore throat
  • rash

FDA Warnings Against Belviq®

They stated that they were unsure of the cause of the increased risk, and would continue to evaluate the trials and alert the public when more information was available.

Another FDA statement was issued in February 2020 which announced that the drug manufacturer Eisai was voluntarily withdrawing Belviq® from the US market.


If you or a loved one has developed pancreatic, colorectal or lung cancer after taking Belviq®, you may require the guidance of an experienced defective drug attorney to discuss your options if this dangerous drug has interrupted your quality of life.

Dangerous drug manufacturers must be held accountable for their actions. At Williams Cedar, our dangerous drug lawyers are dedicated to protecting our clients. Call us today at 215-557-0099  or contact us online to schedule a consultation if you have suffered an injury that might be associated with your use of Belviq®. While our offices are located in Philadelphia, Pennsylvania, and Haddonfield, New Jersey and we are dedicated to serving clients nationwide in bringing defective drug claims against drug manufacturers and distributors.