What is lorcaserin (Belviq)? What is it used for?

Lorcaserin is an orally administered medication that promotes weight loss. It is used with diet and exercise in overweight adults with a weight-related medical problem or obese adults to lose weight and keep it off.

Lorcaserin is a serotonin 2C (5-HT2C) receptor agonist. Although the exact mechanism of action is not known, lorcaserin is thought to selectively stimulate 5-HT2C receptors in the hypothalamus, the area of the brain known to play a major role in regulating hunger and food intake. By activating these receptors, lorcaserin may decrease food consumption by decreasing appetite and making a person feel full even after eating less food than usual.

Lorcaserin was approved by the FDA in June, 2012. Use and distribution of lorcaserin is under strict control by the federal government as it has a potential for abuse and drug dependence. As such, lorcaserin is classified as a schedule IV controlled substance.

What brand names are available for lorcaserin (Belviq)?


Is lorcaserin (Belviq) available as a generic drug?


Do I need a prescription for lorcaserin (Belviq)?


What are the side effects of lorcaserin (Belviq)?

The most common side effects are:

Other less common but serious side effects associated with lorcaserin include:

  • heart valve problems,
  • changes in attention or memory,
  • mental problems,
  • depression or thoughts of suicide,
  • painful erections,
  • slow heartbeat,
  • a drop in blood cell count, and
  • an increase in the hormone, prolactin.


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What is the dosage for lorcaserin (Belviq)?

The recommended dose of lorcaserin is 10 mg administered by mouth twice a day. Lorcaserin may be taken without regard to meals. Lorcaserin should be discontinued in patients who fail to achieve at least a 5% weight loss by week 12 since these patients are not likely to experience meaningful weight loss with continued treatment.

Which drugs or supplements interact with lorcaserin (Belviq)?

Due to the potential risk for serotonin syndrome, a rare but serious disorder caused by abnormally high levels of serotonin, extreme caution should be exercised when using lorcaserin with certain medications. Examples include triptans (a type of medication used for treating migraine headaches), linezolid (Zyvox), tryptophan, lithium (Lithobid, Eskalith), tramadol (Ultram), St. John's Wort, dextromethorphan (a common over-the-counter medicine for treating colds and coughs), and various classes of commonly used antidepressants including selective serotonin reuptake inhibitors (SSRIs), serotonin norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants (TCAs), and monoamine oxidase inhibitors (MOAIs).

Lorcaserin may increase blood levels of drugs broken down by CYP 2D6 liver enzymes. Caution must be used if lorcaserin is used with drugs that are extensively metabolized via this pathway.

Is lorcaserin (Belviq) safe to take if I'm pregnant or breastfeeding?

Weight loss offers no potential benefit during pregnancy and may harm the unborn baby. Use of lorcaserin during pregnancy is not recommended. Lorcaserin is classified as FDA pregnancy risk category X (animal and/or human data demonstrating fetal abnormalities).

It is not known if lorcaserin is excreted in breast milk. Many drugs are excreted in human milk and have the potential of causing harm to the nursing infant. A decision should be made to either discontinue nursing or taking the drug.

What else should I know about lorcaserin (Belviq)?

What preparations of lorcaserin (Belviq) are available?

Oral film coated tablets: 10 mg

How should I keep lorcaserin (Belviq) stored?

Tablets should be stored at room temperature, between 15 C to 30 C (59 F to 86 F).


Lorcaserin (Belviq) is a drug that promotes weight loss by affecting the brain's hypothalamus. People taking lorcaserin eat less and feel fuller. Side effects, drug interactions, and use during pregnancy should be reviewed prior to taking any medication.

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