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Lorcaserin (Oral)

Generic name: lorcaserin [ lor-KA-ser-in ]
Brand names: Belviq, Belviq XR
Drug class: Anorexiants

Medically reviewed by Drugs.com. Last updated on Aug 13, 2023.

Uses for lorcaserin

Lorcaserin is used together with a reduced-calorie diet and proper exercise to help you lose weight. It is also used in overweight people who may also have diabetes, high blood pressure, high cholesterol, or heart disease.

This medicine is available only with your doctor's prescription.

Before using lorcaserin

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Appropriate studies have not been performed on the relationship of age to the effects of lorcaserin in the pediatric population. Safety and efficacy have not been established.

Geriatric

Appropriate studies performed to date have not demonstrated geriatric-specific problems that would limit the usefulness of lorcaserin in the elderly. However, elderly patients are more likely to have kidney problems, which may require caution and an adjustment in the dose for patients receiving lorcaserin.

Breast Feeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Interactions with Medicines

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.

Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

Proper use of lorcaserin

Take this medicine only as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered.

This medicine comes with a patient information insert. Read and follow the instructions carefully. Ask your doctor if you have any questions.

You may take this medicine with or without food.

Carefully follow your doctor's instructions for a reduced-calorie diet plan and regular exercise. Talk with your doctor before starting any exercise program.

Your doctor should tell you to stop taking this medicine if you do not lose a certain amount of weight within the first 12 weeks of treatment.

Dosing

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

Missed Dose

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.

Precautions while using lorcaserin

It is very important that your doctor check your progress at regular visits, to make sure that this medicine is working properly. Blood tests may be needed to check for unwanted effects.

Using this medicine while you are pregnant can harm your unborn baby. Use an effective form of birth control to keep from getting pregnant. If you think you have become pregnant while using this medicine, tell your doctor right away.

Make sure your doctor knows about all the other medicines you are using. This medicine may cause serious conditions, such as serotonin syndrome or neuroleptic malignant syndrome (NMS)-like reactions, when taken with certain medicines. Call your doctor right away if you have a fever, confusion, mental changes, restlessness, fast heartbeat, muscle spasms, trouble walking, nausea, vomiting, or diarrhea.

Check with your doctor right away if you have rapid weight gain, swelling of the ankles, feet, or lower legs, or troubled breathing while using this medicine.

This medicine may cause dizziness, drowsiness, trouble in thinking, or poor judgment. Make sure you know how you react to this medicine before you drive, use machines, or do other jobs that require you to be alert or able to think well.

If you develop any unusual and strange thoughts or behavior while you are taking this medicine, be sure to discuss it with your doctor. Some changes may be more unusual and extreme, such as confusion, worsening of depression, hallucinations (seeing, hearing, or feeling things that are not there), suicidal thoughts, and unusual excitement, nervousness, or irritability.

For patients with diabetes: Weight loss may result in an improvement in your condition, but may increase your chance of having hypoglycemia (low blood sugar). You should check your blood sugar more often before taking this medicine and during Belviq® treatment. If you notice any changes in your blood sugar levels, check with your doctor.

If you experience a prolonged or painful erection for 4 hours or more, contact your doctor immediately. This condition may require prompt medical treatment to prevent serious and permanent damage to your penis.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal (e.g., St. John's wort) or vitamin supplements.

Side Effects of lorcaserin

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

More common

Less common

Rare

Incidence not known

Get emergency help immediately if any of the following symptoms of overdose occur:

Symptoms of overdose

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

Less common

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Commonly used brand name(s)

In the U.S.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.