Praziquantel (By mouth)


Praziquantel (praz-i-KWON-tel)

Treats infections caused by parasites such as liver flukes (worms) or schistosoma (blood flukes).

Brand Name(s)


When This Medicine Should Not Be Used

How to Use This Medicine


  • Your doctor will tell you how much medicine to use. Do not use more than directed.
  • Most people need to wait at least 4 hours after taking one dose of this medicine before they take the next dose. Do not wait more than 6 hours between each dose of this medicine.
  • Swallow the tablet with some liquid during a meal. Swallow the tablet whole. Do not chew.
  • Do not break the tablet unless your doctor tells you to. If you have been told to break your tablet, you can break off a part by pressing the notch with your thumbnails. If one-fourth of a tablet is required, break the tablet from the outer end.

If a dose is missed:

  • Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose.

How to Store and Dispose of This Medicine

  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.
  • Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any outdated medicine or medicine no longer needed.
  • Keep all medicine out of the reach of children. Never share your medicine with anyone.

Drugs and Foods to Avoid

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

  • Make sure your doctor knows if you are using chloroquine (Aralen®), cimetidine (Tagamet®), dexamethasone (Decadron®), erythromycin (E-Mycin®, Ery-Tab®), itraconazole (Sporanox®), or ketoconazole (Nizoral®). Tell your doctor if you are also using medicine for seizures such as carbamazepine, phenobarbital, phenytoin, Dilantin®, or Tegretol®.

Warnings While Using This Medicine

  • Make sure your doctor knows if you are pregnant or breastfeeding. You should not breastfeed on the day you take this medicine and for 72 hours (3 days) afterward.
  • Make sure your doctor knows if you have kidney disease, liver disease, heart disease, or heart rhythm problems.
  • Tell your doctor if you have worm cysts in the brain. Your doctor may want you to be treated in a hospital.
  • This medicine may make you dizzy or drowsy. Avoid driving, using machines, or do anything else that could be dangerous if you are not alert on the day you use this medicine and for 24 hours after you stop taking it.
  • Call your doctor if your symptoms do not improve or if they get worse.
  • Your doctor will check your progress and the effects of this medicine at regular visits. Keep all appointments.

Possible Side Effects While Using This Medicine

Call your doctor right away if you notice any of these side effects:

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
  • Bloody diarrhea, stomach pain.
  • Fast, slow, or uneven heartbeat.
  • Fever, chills, cough, sore throat, and body aches.
  • Seizures.

If you notice these less serious side effects, talk with your doctor:

  • Feeling of constant movement of self or surroundings.
  • Feeling tired or dizzy.
  • Headache.
  • Mild skin rash, hives, or itching skin.
  • Muscle pain or weakness.
  • Nausea, vomiting, upset stomach, diarrhea, or loss of appetite.
  • Sleepiness or unusual drowsiness.
  • Trouble sleeping.

If you notice other side effects that you think are caused by this medicine, tell your doctor

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

Version Info

  • Last reviewed on 10/4/2017

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