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Praziquantel

Medically reviewed by Drugs.com. Last updated on May 23, 2020.

Pronunciation

(pray zi KWON tel)

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Tablet, Oral:

Biltricide: 600 mg [scored]

Generic: 600 mg

Brand Names: U.S.

  • Biltricide

Pharmacologic Category

  • Anthelmintic

Pharmacology

Increases the cell permeability to calcium in schistosomes, causing strong contractions and paralysis of worm musculature leading to detachment of suckers from the blood vessel walls and to dislodgment

Absorption

Oral: 80%

Distribution

CSF concentration is 14% to 20% of plasma concentration

Metabolism

Extensive first-pass effect; metabolized by the liver to hydroxylated and conjugated metabolites

Excretion

Urine ~80% (>99% as metabolites)

Time to Peak

Serum: 1 to 3 hours

Half-Life Elimination

Parent drug: 0.8 to 1.5 hours; Metabolites: 4.5 hours

Protein Binding

~80%

Special Populations: Renal Function Impairment

Excretion may be delayed in patients with renal impairment, but accumulation of unchanged drug would not be expected.

Special Populations: Hepatic Function Impairment

Cmax, AUC, and half-life were significantly elevated in patients with moderate to severe liver impairment.

Use: Labeled Indications

Helminths: Treatment of infections in patients ≥1 year caused by the following: All species of Schistosoma (eg, Schistosoma mekongi, Schistosoma japonicum, Schistosoma mansoni, Schistosoma haematobium) and the liver flukes Clonorchis sinensis/Opisthorchis viverrini

Off Label Uses

Neurocysticercosis, parenchymal

Data from the phase II and phase III portions of a randomized, double blind, placebo-controlled study supports the use of praziquantel (in combination with albendazole) in the treatment of parenchymal neurocysticercosis [Garcia 2014], [Garcia 2016].

Based on the IDSA/ASTMH guidelines for the diagnosis and treatment of neurocysticercosis, praziquantel, in combination with albendazole, is an effective and recommended agent in the management of parenchymal neurocysticercosis with >2 viable cysts.

Tapeworms

Clinical experience suggests the utility of praziquantel in the treatment of a broad range of trematode and cestode infections [Liu 1996].

Contraindications

Hypersensitivity to praziquantel or any component of the formulation; ocular cysticercosis; concomitant administration with strong cytochrome P450 (CYP450) inducers, such as rifampin

Dosing: Adult

Clonorchiasis/opisthorchiasis: Oral: 25 mg/kg/dose 3 times daily for 1 to 2 days (Drugs for Parasitic Infections 2013; manufacturer's labeling).

Neurocysticercosis, parenchymal (>2 viable cysts) (off-label use): Oral: 50 mg/kg/day in 3 divided doses (in combination with albendazole) for 10 to 14 days; may be repeated if persistent viable lesions on 6-month follow-up imaging (Garcia 2014; IDSA/ASTMH [White 2018]). Note: Initiate adjunctive corticosteroid therapy prior to initiation of antiparasitic therapy. Antiparasitic therapy should not be initiated in patients with untreated hydrocephalus, calcified lesions, or cysticercal encephalitis; consult an infectious diseases specialist for specific treatment recommendations (IDSA/ASTMH [White 2018]).

Schistosomiasis: Note: Repeat treatment may be needed in 2 to 4 weeks to increase effectiveness (CDC 2018c).

S. haematobium, Schistosoma intercalatum, or S. mansoni: Oral: 40 mg/kg/day as a single dose or in 2 divided doses for 1 day (CDC 2018c; Drugs for Parasitic Infections 2013).

S. japonicum or S. mekongi: Oral: 60 mg/kg/day in 2 or 3 divided doses for 1 day (CDC 2018c; Drugs for Parasitic Infections 2013; manufacturer's labeling).

Tapeworms (off-label use): Oral: 5 to 10 mg/kg as a single dose (25 mg/kg for Hymenolepis nana) (Drugs for Parasitic Infections 2013; Liu 1996).

Dosing: Geriatric

Refer to adult dosing.

Dosing: Pediatric

Note: Dosing interval and duration highly variable dependent on condition; for 3 times daily doses, intervals of 4 to 6 hours are suggested.

Flukes:

Clonorchiasis (Clonorchis sinensis [Chinese liver fluke]); Opisthorchiasis (Opisthorchis viverrini [Southeast Asian liver fluke]): Children and Adolescents: Oral: 25 mg/kg/dose 3 times daily at 4- to 6-hour intervals for 1 to 2 days (CDC 2018a; CDC 2018b; Red Book [AAP 2018])

Fasciolopsiasis (Fasciolopsis buski [intestinal fluke]):Limited data available: Children and Adolescents: Oral: 25 mg/kg/dose 3 times daily for 1 day (CDC 2012b; Red Book [AAP 2018])

Paragonimiasis (Paragonimus spp. [lung fluke]): Limited data available: Children and Adolescents: Oral: 25 mg/kg/dose 3 times daily for 2 to 3 days (CDC 2013a; Red Book [AAP 2018])

Schistosomiasis (Bilharziasis):

Treatment (CDC 2018c; Red Book [AAP 2018]): Note: Repeat treatment may be needed in 2 to 4 weeks to increase effectiveness

Schistosoma japonicum, Schistosoma mekongi: Children and Adolescents: Oral: 20 mg/kg/dose 3 times daily for 1 day

Schistosoma mansoni, Schistosoma haematobium, Schistosoma intercalatum: Children and Adolescents: Oral: 20 mg/kg/dose twice daily for 1 day

Control programs for endemic areas: Limited data available: Infants, Children, and Adolescents: Oral: 40 mg/kg as a single dose (WHO 2006; WHO 2010); a single dose of 40 mg/kg has been successfully used to treat urogenital S. haematobium in children 1 to 10 years of age (Wami 2016) and S. mansoni in population that included infants (age range: 5 months to 7 years) (Sousa-Figueiredo 2012); however, pharmacokinetic data suggests a lower cure rate in infants and preschool children; one possible explanation is that higher doses may be necessary in younger patients due to pharmacokinetic/dynamic differences; in preschool children, a single dose of 60 mg/kg was successfully used in children 3 to 8 years of age in a hyperendemic area to treat S. mansoni (Bustinduy 2016).

Tapeworms: Limited data available:

Diphyllobothrium latum (fish), Taenia saginata (beef), Taenia solium (pork); intestinal (adult) stage: Children and Adolescents: Oral: 5 to 10 mg/kg as a single dose (CDC 2012a; CDC 2013b; Red Book [AAP 2018])

Dipylidium caninum (dog); intestinal (adult) stage: Infants ≥6 months, Children, and Adolescents: Oral: 5 to 10 mg/kg as a single dose (CDC 2016; Red Book [AAP 2018])

Hymenolepis nana (dwarf tapeworm): Children and Adolescents: Oral: 25 mg/kg as a single dose (CDC 2012c)

Neurocysticercosis (Taenia solium [pork tapeworm]); tissue (larvae) stage: Children and Adolescents: Oral: 50 mg/kg/day for 15 days (CDC 2017); Note: May be used in conjunction with antiseizure medication and/or corticosteroids.

Administration

Administer tablets with water during meals. Tablets should be promptly swallowed to avoid bitter taste that may cause gagging or vomiting. Tablets may be halved or quartered; do not chew. Tablets may be crushed or disintegrated and mixed with semi-solid food or liquid; use within 1 hour of mixing. Tablets are scored and may be split into four 150 mg segments.

Storage

Store below 30°C (86°F).

Drug Interactions

Abametapir: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Avoid combination

Aprepitant: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Chloroquine: May decrease the serum concentration of Praziquantel. Monitor therapy

Cimetidine: May increase the serum concentration of Praziquantel. Monitor therapy

Clofazimine: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Conivaptan: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Avoid combination

CYP3A4 Inducers (Moderate): May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

CYP3A4 Inducers (Strong): May decrease the serum concentration of Praziquantel. Management: Use of praziquantel with strong CYP3A4 inducers is contraindicated. Discontinue rifampin 4 weeks prior to initiation of praziquantel therapy. Rifampin may be resumed the day following praziquantel completion. Avoid combination

CYP3A4 Inhibitors (Strong): May increase the serum concentration of Praziquantel. Monitor therapy

Dabrafenib: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Management: Seek alternatives to the CYP3A4 substrate when possible. If concomitant therapy cannot be avoided, monitor clinical effects of the substrate closely (particularly therapeutic effects). Consider therapy modification

Deferasirox: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Duvelisib: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Erdafitinib: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Erdafitinib: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Fosaprepitant: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Fosnetupitant: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Fusidic Acid (Systemic): May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Avoid combination

Grapefruit Juice: May increase the serum concentration of Praziquantel. Monitor therapy

Idelalisib: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Avoid combination

Ivosidenib: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Larotrectinib: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

MiFEPRIStone: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Management: Minimize doses of CYP3A4 substrates, and monitor for increased concentrations/toxicity, during and 2 weeks following treatment with mifepristone. Avoid cyclosporine, dihydroergotamine, ergotamine, fentanyl, pimozide, quinidine, sirolimus, and tacrolimus. Consider therapy modification

Netupitant: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Palbociclib: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Sarilumab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Siltuximab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Simeprevir: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Monitor therapy

Stiripentol: May increase the serum concentration of CYP3A4 Substrates (High risk with Inhibitors). Management: Use of stiripentol with CYP3A4 substrates that are considered to have a narrow therapeutic index should be avoided due to the increased risk for adverse effects and toxicity. Any CYP3A4 substrate used with stiripentol requires closer monitoring. Consider therapy modification

Tocilizumab: May decrease the serum concentration of CYP3A4 Substrates (High risk with Inducers). Monitor therapy

Adverse Reactions

Frequency not defined. May be more frequent and/or serious in patients with a heavy worm burden.

Central nervous system: Dizziness, headache, malaise

Dermatologic: Urticaria

Gastrointestinal: Abdominal distress, nausea

Miscellaneous: Fever

<1%, postmarketing and/or case reports: Abdominal pain, anorexia, atrioventricular block, bloody diarrhea, bradycardia, cardiac arrhythmia, drowsiness, ectopic beats, eosinophilia, fatigue, hypersensitivity, hypersensitivity reaction, increased liver enzymes (minimal), myalgia, paradoxical reaction (in schistosomiasis), polyserositis, pruritus, seizure, serum sickness (in schistosomiasis; Jarisch-Herxheimer-like reaction), skin rash, ventricular fibrillation, vertigo, vomiting, weakness

Warnings/Precautions

Disease-related concerns:

• Cardiac arrhythmias: Monitor patients with cardiac arrhythmias during treatment; bradycardia, ectopic rhythms, ventricular fibrillation, and AV blocks have been observed with praziquantel administration.

• Central nervous system effects: Praziquantel may exacerbate central nervous system pathology due to schistosomiasis, paragonimiasis, or Taenia solium cysticercosis. Assess whether the potential benefit justifies the potential risk in patients with a history of seizures and/or other signs of potential central nervous system involvement such as subcutaneous nodules suggestive of cysticercosis.

• Hepatic impairment: Use with caution in patients with moderate to severe hepatic impairment; reduced liver drug metabolism may result in higher and longer lasting plasma concentrations of unmetabolized praziquantel.

• Neurocysticercosis: Appropriate use: Antiparasitic therapy may worsen symptoms of neurocysticercosis by inducing an inflammatory response; adjunctive corticosteroid therapy should be started before initiation of antiparasitic therapy. Antiparasitic therapy should not be initiated in patients with untreated hydrocephalus, calcified lesions, or cysticercal encephalitis. Perform funduscopic exam prior to initiation of antiparasitic therapy to exclude intraocular cysticerci; antiparasitic therapy may lead to blindness in some cases with unsuspected intraocular parasites (IDSA/ASTMH [White 2018]).

• Schistosomiasis: Praziquantel may not be effective against migrating schistosomulae; observational data indicate that praziquantel treatment in the acute phase of the infection may not prevent progression from asymptomatic to acute schistosomiasis, or from asymptomatic/acute disease to chronic disease. In addition, use in patients with schistosomiasis may be associated with clinical deterioration such as paradoxical reactions or serum sickness Jarisch-Herxheimer-like reactions, which is a sudden inflammatory immune response likely caused by the release of schistosomal antigens. Such reactions typically occur during the acute disease phase, and may lead to life-threatening events such as respiratory failure, encephalopathy, papilledema, and/or cerebral vasculitis.

Concurrent drug therapy issues:

• Drug/drug interactions: Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information. Therapeutic levels of praziquantel may not be achieved with concurrent administration of strong inducers of cytochrome P450 (eg, rifampin); concurrent use is contraindicated.

Other warnings/precautions:

• Patient information: Patients should be instructed to not drive or operate machinery on the day of treatment and the day after treatment.

Monitoring Parameters

Liver function tests; monitor patients with cardiac irregularities during treatment; monitor for seizures; culture urine or feces for ova prior to instituting therapy

Pregnancy Considerations

Based on available data, an increased risk of adverse fetal or maternal outcomes has not been observed following use of praziquantel for the treatment of Schistosoma infection during pregnancy (Friedman 2018).

In areas where schistosomiasis and soil-transmitted helminthiasis is endemic, the World Health Organization recommends treatment with praziquantel during any trimester of pregnancy (WHO 2006). Non-emergent treatment of neurocysticercosis can be delayed until after pregnancy (IDSA/ASTMH [White 2018]).

Patient Education

What is this drug used for?

• It is used to treat infections caused by worms.

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Loss of strength and energy

• Dizziness

• Headache

• Abdominal pain

• Nausea

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Seizures

• Fast heartbeat

• Slow heartbeat

• Abnormal heartbeat

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.

Note: This is not a comprehensive list of all side effects. Talk to your doctor if you have questions.

Consumer Information Use and Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a limited summary of general information about the medicine's uses from the patient education leaflet and is not intended to be comprehensive. This limited summary does NOT include all information available about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not intended to provide medical advice, diagnosis or treatment and does not replace information you receive from the healthcare provider. For a more detailed summary of information about the risks and benefits of using this medicine, please speak with your healthcare provider and review the entire patient education leaflet.

Further information

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