Praziquantel

Praziquantel
Clinical data
Pronunciation	/ˌpræzɪˈkwɒntɛl/
Trade names	Biltricide
Other names	PZQ
AHFS/Drugs.com	Monograph
MedlinePlus	a608048
License data	US DailyMed: Praziquantel;
Pregnancy; category	AU: B1;
Routes of; administration	by mouth
ATC code	P02BA01 (WHO) QP52AA01 (WHO) QP52AA51 (WHO);
Legal status
Legal status	CA: ℞-only; US: ℞-only (human use),; OTC (veterinary use); EU: Rx-only;
Pharmacokinetic data
Bioavailability	Relatively small
Metabolism	Liver
Elimination half-life	0.8–1.5 hours (main metabolites: 4–5 hours)
Excretion	Kidney (mainly)
Identifiers
	IUPAC name (RS)-2-(Cyclohexylcarbonyl)-1,2,3,6,7,11b-hexahydro-4H-pyrazino[2,1-a]isoquinolin-4-one;
CAS Number	55268-74-1 ;
PubChem CID	4891;
DrugBank	DB01058 ;
ChemSpider	4722 ;
UNII	6490C9U457;
KEGG	D00471 ;
ChEMBL	ChEMBL976 ;
CompTox Dashboard (EPA)	DTXSID9021182 ;
ECHA InfoCard	100.054.126
Chemical and physical data
Formula	C19H24N2O2
Molar mass	312.413 g·mol−1
3D model (JSmol)	Interactive image;
Melting point	136 to 138 °C (277 to 280 °F)
	SMILES O=C4N2C(c1c(cccc1)CC2)CN(C(=O)C3CCCCC3)C4;
	InChI InChI=1S/C19H24N2O2/c22-18-13-20(19(23)15-7-2-1-3-8-15)12-17-16-9-5-4-6-14(16)10-11-21(17)18/h4-6,9,15,17H,1-3,7-8,10-13H2 ; Key:FSVJFNAIGNNGKK-UHFFFAOYSA-N ;
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Praziquantel, sold under the brandname Biltricide among others, is a medication used to treat a number of types of parasitic worm infections in mammals, birds, amphibians, reptiles, and fish. In humans specifically, it is used to treat schistosomiasis, clonorchiasis, opisthorchiasis, tapeworm infections, cysticercosis, echinococcosis, paragonimiasis, fasciolopsiasis, and fasciolosis. It should not be used for worm infections of the eye. It is taken by mouth.

Side effects in humans may include poor coordination, abdominal pain, vomiting, headache, and allergic reactions. While it may be used during pregnancy, it is not recommended for use during breastfeeding. Praziquantel is in the anthelmintic class of medications. It works partly by affecting the function of the worm's sucker.

Praziquantel was approved for medical use in the United States in 1982, and in the European Union in April 2025. It is on the World Health Organization's List of Essential Medicines.