Praziquantel Oral: Uses, Side Effects, Interactions, Pictures, Warnings & Dosing

Take this medication by mouth with a meal as directed by your doctor, usually 3 times a day (4 to 6 hours apart) for 1 day. Quickly swallow the tablets or tablet segments with a full glass of water (8 ounces or 240 milliliters). Do not chew or suck the tablets because the bitter taste of praziquantel may cause gagging or vomiting. Your doctor may direct you to take this medication fewer than 3 times a day or to take it for longer than 1 day. Follow your doctor's directions exactly.

If you have trouble swallowing the tablets or tablet segments, you may crush the medication and mix it in soft foods or liquids. Take the mixture within 1 hour of mixing.

The dosage is based on your medical condition, weight, and response to treatment. Tablets are scored with lines. You may need to break the tablet to get the correct dose. Ask your pharmacist for directions on breaking the tablet to get the right dose for you.

Avoid eating grapefruit or drinking grapefruit juice while using this medication unless your doctor or pharmacist says you may do so safely. Grapefruit can increase the chance of side effects with this medicine. Ask your doctor or pharmacist for more details.

Your symptoms may worsen when you start taking praziquantel. Tell your doctor right away if your condition lasts or worsens.

Warnings for Biltricide

Included as part of the PRECAUTIONS section.

Precautions for Biltricide

Clinical Deterioration

The use of Biltricide in patients with schistosomiasis may be associated with clinical deterioration (for example, paradoxical reactions, serum sickness Jarisch-Herxheimer like reactions: sudden inflammatory immune response suspected to be caused by the release of schistosomal antigens). These reactions predominantly occur in patients treated during the acute phase of schistosomiasis. They may lead to potentially life-threatening events, for example, respiratory failure, encephalopathy, papilledema, and/or cerebral vasculitis.

Central Nervous System (CNS) Effects

Biltricide can exacerbate central nervous system pathology due to schistosomiasis, paragonimiasis, or Taenia solium cysticercosis. As a general rule, consider whether to administer Biltricide to individuals reporting a history of epilepsy and/or other signs of potential central nervous systems involvement such as subcutaneous nodules suggestive of cysticercosis unless the potential benefit justifies the potential risk. Hospitalize the patient for duration of treatment when schistosomiasis or fluke infection is found to be associated with cerebral cysticercosis.

Potential Lack Of Efficacy During The Acute Phase Of Schistosomiasis

Data from two observational cohort studies in patients indicate that treatment with Biltricide in the acute phase of infection may not prevent progression from asymptomatic infection to acute schistosomiasis, or from asymptomatic infection/acute schistosomiasis into chronic phase.

Cardiac Arrhythmias

Bradycardia, ectopic rhythms, ventricular fibrillation, and AV blocks has been observed with Biltricide administration. Monitor patients with cardiac arrhythmias during treatment.

Hepatic Impairment In Hepatosplenic Schistosomiasis Patients

Reduced hepatic metabolism of praziquantel results in higher and sustained plasma concentrations of unmetabolized praziquantel in patients with liver impairment [see CLINICAL PHARMACOLOGY]. Monitor patients for adverse reactions when administering the recommended dose of Biltricide to hepatosplenic schistosomiasis patients with moderate or severe liver impairment (Child-Pugh Class B or C).

Concomitant Administration With Cytochrome P450 Enzyme Inducers

Strong Cytochrome P450 3A Enzyme (CYP 3A) Inducers

Concomitant administration of strong CYP 3A inducers, such as rifampin, with Biltricide is contraindicated since therapeutically effective levels of praziquantel are unlikely to be achieved. [see CONTRAINDICATIONS, DRUG INTERACTIONS, and CLINICAL PHARMACOLOGY].

Moderate CYP 3A Inducers

Avoid concomitant administration of Biltricide with moderate CYP 3A inducers, such as efavirenz, due to risk of a clinically significant decrease in praziquantel plasma concentrations which may lead to reduced therapeutic effect of Biltricide. [see DRUG INTERACTIONS].

In patients receiving a clinically significant CYP 3A inducer drug who need immediate treatment for schistosomiasis, alternative agents for schistosomiasis should be considered, where possible. If Biltricide is necessary immediately, increase monitoring for reduced anthelmintic efficacy associated with Biltricide [see DRUG INTERACTIONS].

In patients receiving a clinically significant CYP 3A inducer drug whose treatment could be delayed, discontinue the CYP 3A inducer drug at least 2 weeks to 4 weeks before administration of Biltricide and, where possible, consider starting alternative medications that are not CYP 3A inducers. The CYP 3A inducer drug can be restarted one day after completion of Biltricide treatment, if needed [see DRUG INTERACTIONS]

Nonclinical Toxicology

Carcinogenesis, Mutagenesis, Impairment Of Fertility

Mutagenicity studies of praziquantel published in the scientific literature are inconclusive. Long term oral carcinogenicity studies in rats and golden hamsters did not reveal any carcinogenic effect at doses up to 250 mg/kg/day (about half of the human daily dose based on body surface area). Praziquantel had no effect on fertility and general reproductive performance of male and female rats when given at oral doses ranging from 30 to 300 mg/kg body weight (up to 0.65 times the human daily dose based on body surface area).

Use In Specific Populations

Pregnancy

Risk Summary

Published studies have not identified an association with Biltricide use during pregnancy and major birth defects, miscarriage or adverse maternal or fetal outcomes (see Data). In animal reproduction studies conducted in pregnant rats and rabbits no adverse developmental outcomes were observed with oral administration of praziquantel during organogenesis at approximately 0.65 times (rats) or 1.3 times (rabbits) the highest recommended human daily dose of 75 mg/kg/day, based on body surface area.

The estimated background risk of major birth defects and miscarriage for the indicated population are unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2 to 4% and 15 to 20%, respectively.

Data

Human Data

Two randomized controlled clinical trials have been conducted using praziquantel for the treatment of schistosoma infection in pregnant women. In one randomized controlled trial in pregnant women with schistosoma (S. japonicum) infection, 186 pregnant women were treated with praziquantel compared to 184 women who received placebo. Treatment with praziquantel during pregnancy had no effect on birthweight, and there were no differences in rates of miscarriage, fetal death and major birth defects between the praziquantel­treated and control patients. In another randomized controlled trial that included 2507 pregnant women in Uganda, 18% of women were infected with schistosoma infection. Treatment with praziquantel during pregnancy had no effect on mean birth weight, perinatal mortality or major birth defects.

In other published studies, including a retrospective observational study, case series and case reports, there have been no reports of major birth defects, stillbirths or other adverse pregnancy outcomes associated with the use of praziquantel during pregnancy.

Animal Data

No evidence of fetal harm was observed in rats and rabbits at praziquantel dose levels of 30 to 300 mg/kg body weight given repeatedly by oral administration during the period of organogenesis. These doses were up to 0.65 times (rats) or 1.3 times (rabbits) the highest recommended human daily dose of 75 mg/kg/day, based on body surface area.

Lactation

Risk Summary

Limited data from published literature reports the presence of praziquantel in human milk at low concentrations. There is no information on the effects of praziquantel in the breastfed infant or effects on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for Biltricide and any potential adverse effects on the breastfed infant from Biltricide or from the underlying maternal condition.

Pediatric Use

Safety and dosing recommendations of Biltricide in pediatric patients 1 to 17 years have been established. Safety of Biltricide in pediatric patients younger than 1 year of age has not been established.

Post-marketing experience and published literature indicates that pediatric patients 1 to 17 years of age treated with praziquantel experience similar adverse reactions as adults treated with praziquantel [see ADVERSE REACTIONS].

Geriatric Use

Clinical studies of Biltricide did not include a sufficient number of subjects ages 65 and over to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences in responses between the elderly and younger patients, but greater sensitivity of some older patients cannot be ruled out. This drug is known to be substantially excreted by the kidney. Because elderly patients are more likely to have decreased renal function, the risk of toxic reactions to this drug may be greater in these patients [see CLINICAL PHARMACOLOGY].

Hepatic Impairment

Following oral administration of Biltricide to patients with liver impairment, reduced hepatic metabolism of praziquantel results in higher and sustained plasma concentrations of unmetabolized praziquantel [see CLINICAL PHARMACOLOGY]. Monitor patients for adverse reactions when administering the recommended dose of Biltricide to hepatosplenic schistosomiasis patients with moderate or severe liver impairment (Child-Pugh Class B or C).

Renal Impairment

No dosage adjustment of Biltricide is necessary in patients with renal impairment. Nephrotoxic effects of Biltricide or its metabolites are not known [see CLINICAL PHARMACOLOGY].