Lorcaserin extended-release tablets

What is this medication?

LORCASERIN (lor ca SER in) is used to help people lose weight and maintain weight loss. This medicine should be used with a reduced-calorie diet and, if appropriate, an exercise program.

This medicine may be used for other purposes; ask your healthcare provider or pharmacist if you have questions.



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What should I tell my care team before I take this medication?

They need to know if you have any of these conditions:

  • Anatomical deformation of the penis, Peyronie's disease, or history of priapism (painful and prolonged erection).
  • Diabetes.
  • Heart disease.
  • History of sickle cell anemia, multiple myeloma, or leukemia.
  • History of irregular heartbeat.
  • Kidney disease.
  • Liver disease.
  • Suicidal thoughts, plans, or attempt; a previous suicide attempt by you or a family member.
  • An unusual or allergic reaction to lorcaserin, other medicines, foods, dyes, or preservatives.
  • Pregnant or trying to get pregnant.
  • Breast-feeding.

How should I use this medication?

Take this medicine by mouth with a glass of water. Follow the directions on the prescription label. Do not cut, crush or chew this medicine. You can take it with or without food. Take your medicine at regular intervals. Do not take it more often than directed. Do not stop taking except on your doctor's advice.

Talk to your pediatrician regarding the use of this medicine in children. Special care may be needed.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.

NOTE: This medicine is only for you. Do not share this medicine with others.


What if I miss a dose?

If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

What may interact with this medication?

  • Cabergoline.
  • Certain medicines for depression, anxiety, or psychotic disturbances.
  • Certain medicines for erectile dysfunction.
  • Certain medicines for migraine headache like almotriptan, eletriptan, frovatriptan, naratriptan, rizatriptan, sumatriptan, zolmitriptan.
  • Dextromethorphan.
  • Linezolid.
  • Lithium.
  • Medicines for diabetes.
  • Other weight loss products.
  • Tramadol.
  • St. John’s Wort.
  • Stimulant medicines for attention disorders, weight loss, or to stay awake.
  • Tryptophan.

This list may not describe all possible interactions. Give your healthcare provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.


What should I watch for while using this medication?

Visit your healthcare professional for regular checks on your progress. You may need blood work done while you are taking this medicine.

Do not drive, use machinery, or do anything that needs mental alertness until you know how this medicine affects you.

This medicine may affect blood sugar levels. Ask your healthcare provider if changes in diet or medicines are needed if you have diabetes.

Patients and their families should watch out for new or worsening depression or thoughts of suicide. Also watch out for sudden changes in feelings such as feeling anxious, agitated, panicky, irritable, hostile, aggressive, impulsive, severely restless, overly excited and hyperactive, or not being able to sleep. If this happens, especially at the beginning of treatment or after a change in dose, call your healthcare professional.

Contact your doctor or health care professional right away if you are a man with an erection that lasts longer than 4 hours or if the erection becomes painful. This may be a sign of serious problem and must be treated right away to prevent permanent damage.

Women should inform their healthcare provider if they wish to become pregnant or think they might be pregnant. Losing weight while pregnant is not advised and may cause harm to the unborn child. Talk to your healthcare provider for more information.

This medicine may increase your risk of cancer. Talk to your healthcare professional about risks and benefits.

What side effects may I notice from receiving this medication?

Side effects that you should report to your doctor or health care professional as soon as possible:

  • Allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue.
  • Abnormal production of milk.
  • Breast enlargement in both males and females.
  • Breathing problems.
  • Changes in emotions or moods.
  • Changes in vision.
  • Confusion.
  • Fast or irregular heartbeat.
  • Feeling faint or lightheaded, falls.
  • Fever or chills, sore throat.
  • Hallucinations.
  • High or low blood pressure.
  • Males: prolonged or painful erection lasting more than 4 hours.
  • Menstrual changes.
  • Restlessness.
  • Signs and symptoms of low blood sugar such as feeling anxious; confusion; dizziness; increased hunger; unusually weak or tired; increased sweating; shakiness; cold, clammy skin; irritable; headache; blurred vision; fast heartbeat; loss of consciousness.
  • Slow or irregular heartbeat.
  • Stiff muscles.
  • Sweating.
  • Suicidal thoughts.
  • Swelling of the ankles, feet, hands.
  • Unusually weak or tired.
  • Vomiting.

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

  • Back pain.
  • Constipation.
  • Dizziness.
  • Dry mouth.
  • Headache.
  • Nausea.
  • Tiredness.

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Where should I keep my medication?

Keep out of the reach of children. This medicine can be abused. Keep your medicine in a safe place to protect it from theft. Do not share this medicine with anyone. Selling or giving away this medicine is dangerous and against the law.

Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Throw away any unused medicine after the expiration date.

NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

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Note: Introduction and Additional Common Questions written and medically approved by Cleveland Clinic professionals.

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