What is Lorcaserin: Uses, Dosage, Side Effects and More

Lorcaserin was a prescription weight loss medication that helped people lose weight by making them feel full sooner during meals. However, the FDA withdrew this medication from the U.S. market in February 2020 due to safety concerns about increased cancer risk. If you're currently taking lorcaserin or considering weight loss options, it's important to understand what happened and explore safer alternatives with your doctor.

What is Lorcaserin?

Lorcaserin was an appetite suppressant medication designed to help adults lose weight when combined with diet and exercise. It worked by targeting serotonin receptors in your brain that control feelings of hunger and fullness. The medication was sold under the brand name Belviq and Belviq XR.

The drug belonged to a class of medications called serotonin 2C receptor agonists. Think of it as a chemical messenger that told your brain you were satisfied with less food. This helped people eat smaller portions and feel full longer after meals.

Lorcaserin was only approved for adults with a body mass index (BMI) of 30 or higher, or those with a BMI of 27 or higher who also had weight-related health conditions like diabetes or high blood pressure.

What Was Lorcaserin Used For?

Lorcaserin was prescribed specifically for chronic weight management in adults struggling with obesity. It wasn't a quick fix or diet pill, but rather a tool to support long-term weight loss efforts alongside healthy eating and regular physical activity.

Doctors typically prescribed lorcaserin for people who had tried traditional weight loss methods without success. The medication was meant to help break the cycle of overeating by reducing appetite and food cravings. Many patients found it easier to stick to their calorie goals when taking the medication.

The drug was also used for people with weight-related medical conditions. These included type 2 diabetes, high blood pressure, high cholesterol, and sleep apnea. Weight loss often helped improve these conditions, making lorcaserin a valuable treatment option before its withdrawal.

How Did Lorcaserin Work?

Lorcaserin worked by activating specific serotonin receptors in your brain's appetite control center. These receptors, called 5-HT2C receptors, play a key role in telling your body when you've had enough to eat. When activated, they sent signals that you were satisfied and full.

The medication was considered moderately effective rather than a strong weight loss drug. Most people who took lorcaserin lost about 5 to 10 percent of their body weight over the course of a year. While this might not sound dramatic, even modest weight loss can significantly improve health outcomes for people with obesity.

Unlike some other appetite suppressants, lorcaserin was designed to be selective in its action. It primarily targeted the receptors involved in appetite control rather than affecting other systems in your body. This selectivity was intended to reduce side effects compared to older weight loss medications.

How Should Lorcaserin Have Been Taken?

Lorcaserin was typically taken twice daily with or without food. The standard immediate-release version required two 10mg doses per day, while the extended-release version (Belviq XR) was taken once daily as a 20mg dose. Your doctor would have determined the best dosing schedule based on your individual needs.

The medication could be taken with water, milk, or juice. There were no specific food restrictions, though taking it with a meal sometimes helped reduce stomach upset in sensitive individuals. Most doctors recommended taking the medication at the same times each day to maintain consistent levels in your system.

It was important to continue following a reduced-calorie diet and exercise program while taking lorcaserin. The medication worked best when combined with lifestyle changes, not as a replacement for healthy habits. Your doctor would have provided specific dietary guidelines tailored to your weight loss goals.

How Long Should Lorcaserin Have Been Taken?

Lorcaserin was designed for long-term use, but doctors typically evaluated its effectiveness after 12 weeks of treatment. If you hadn't lost at least 5 percent of your initial body weight by this point, your doctor would likely have discontinued the medication since it wasn't providing meaningful benefit.

For those who did respond well, lorcaserin could be continued for extended periods under medical supervision. Some people took it for several years as part of their ongoing weight management plan. Regular check-ups were essential to monitor both effectiveness and potential side effects.

The decision to stop taking lorcaserin was always made in consultation with your healthcare provider. Stopping suddenly didn't cause withdrawal symptoms, but many people found their appetite returned to previous levels relatively quickly after discontinuation.

What Were the Side Effects of Lorcaserin?

Like all medications, lorcaserin could cause side effects, though many people tolerated it well. The most common side effects were generally mild and often improved as your body adjusted to the medication. However, the serious concern that led to its withdrawal was an increased risk of cancer.

Here are the most frequently reported side effects that people experienced while taking lorcaserin:

• Headache and dizziness
• Nausea and upset stomach
• Fatigue and weakness
• Dry mouth
• Constipation
• Back pain
• Cough and upper respiratory infections

These common side effects were usually manageable and temporary. Most people found that drinking plenty of water, eating regular meals, and getting adequate rest helped minimize these symptoms.

More serious but rare side effects included serotonin syndrome, especially when combined with other medications that affect serotonin levels. This condition caused symptoms like confusion, rapid heart rate, high blood pressure, and muscle stiffness. Additionally, some people experienced heart valve problems, though this was uncommon.

The most concerning finding was an increased risk of cancer, particularly lung, pancreatic, and colorectal cancers. This discovery during a long-term safety study led to the FDA's decision to remove lorcaserin from the market in February 2020.

Who Should Not Have Taken Lorcaserin?

Several groups of people were advised not to take lorcaserin due to increased risks or reduced effectiveness. Pregnant and breastfeeding women were strictly prohibited from using this medication since weight loss during these periods could harm both mother and baby.

People with certain medical conditions needed to avoid lorcaserin entirely. This included individuals with severe kidney or liver disease, as these organs were responsible for processing the medication. Those with a history of heart valve problems were also advised against taking lorcaserin due to potential cardiac complications.

Additionally, people taking certain medications couldn't safely use lorcaserin. This included those on MAO inhibitors, some antidepressants, migraine medications, and other drugs that affect serotonin levels. The combination could lead to dangerous serotonin syndrome.

Lorcaserin Brand Names

Lorcaserin was marketed under two main brand names in the United States. Belviq was the immediate-release version that required twice-daily dosing, while Belviq XR was the extended-release formulation taken once daily. Both versions contained the same active ingredient but were designed for different dosing schedules.

The medication was manufactured by Arena Pharmaceuticals and later marketed by Eisai Inc. Other countries may have had different brand names, but the active ingredient remained lorcaserin hydrochloride regardless of the manufacturer or brand name.

Since the FDA withdrawal in 2020, these brand names are no longer available in the United States. Any remaining supplies were required to be removed from pharmacies and returned to manufacturers.

Lorcaserin Alternatives

Several FDA-approved weight loss medications are available as alternatives to lorcaserin. These options work through different mechanisms and may be suitable depending on your individual health profile and weight loss goals. Your doctor can help determine which alternative might work best for you.

Current prescription weight loss medications include orlistat (Xenical), phentermine-topiramate (Qsymia), naltrexone-bupropion (Contrave), and liraglutide (Saxenda). Each has its own set of benefits and potential side effects, so careful evaluation with your healthcare provider is essential.

Non-medication alternatives include structured weight loss programs, meal replacement plans, and bariatric surgery for those who qualify. Many people find success with comprehensive lifestyle modification programs that combine dietary counseling, exercise guidance, and behavioral support.

Was Lorcaserin Better Than Other Weight Loss Medications?

Lorcaserin's effectiveness was similar to other prescription weight loss medications available at the time. Most people lost about 5 to 10 percent of their body weight over a year, which was comparable to other FDA-approved options. The main advantage was its relatively mild side effect profile compared to some alternatives.

However, the cancer risk discovered in long-term studies ultimately outweighed any benefits lorcaserin might have offered. This is why the FDA concluded that the risks exceeded the benefits and requested its removal from the market. Other weight loss medications continue to be available because their benefit-to-risk profiles remain favorable.

Each weight loss medication has unique characteristics that may make it more or less suitable for different individuals. What matters most is finding a safe, effective option that works with your specific health conditions and lifestyle under proper medical supervision.