Bithionol

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [2]

Overview

Bithionol is an anthelmintic used to treat "Anoplocephala perfoliata" (tapeworms) in horses and Fasciola hepatica (liver flukes).

Category

Antiparasite

Brand Names

Bithionol is investigational in the U.S. The drug can be obtained from the Centers for Disease Control (CDC) Drug Service, CDC, Atlanta, Georgia 30333 (404-639-3670; evenings, weekends, or holidays: 404-639-2888).

Prescribing Information

Dosage

Adult Normal Dosage

Oral route

1) The recommended oral dose of bithionol for the treatment of Fascioliasis, and as alternative therapy in Paragonimiasis, is 30 to 50 milligrams/kilogram on alternate days for 10 to 15 doses.

2) Bithionol is usually given in 2 or 3 divided doses, and after meals to minimize gastrointestinal symptoms.

Pediatric Normal Dosage

Oral route

1) The recommended pediatric oral dose of bithionol for the treatment of Fascioliasis, and as alternative therapy in Paragonimiasis, is 30 to 50 milligrams/kilogram on alternate days for 10 to 15 doses.

2) Bithionol is usually given in 2 or 3 divided doses, and after meals to minimize gastrointestinal symptoms.

Pharmacokinetics

Onset

a) Fascioliasis, 2 to 9 days.

b) Resolution of fever has been reported 2 days after initiation of BITHIONOL therapy in fascioliasis, with eradication of ova in stools after 9 days.

c) Paragonimiasis, 3 to 5 days. (Significant improvement of hemoptysis in paragonimiasis has been reported after the third dose of oral BITHIONOL. Eradication of Paragonimus westermani ova has occurred after the fifth dose.)

Metabolism

• Metabolism Sites and Kinetics: Not extensively studied in humans. Animal studies suggest that BITHIONOL is metabolized in the liver, with metabolites being excreted in bile and urine.

Contraindications

• Previous hypersensitivity to BITHIONOL

Precautions

• Renal insufficiency (potential accumulation)

• Cardiovascular disease

• Peptic ulcer disease

• Asthma or other allergic-type disorders

Adverse Reactions

Cardiovascular Effects

• Extrasystoles, first-degree heart block, and hypertension have been reported rarely after bithionol administration.

• Blood pressure irregularities, and errors in cardiac conduction are reported in association with the therapeutic use of bithionol.

• Hypotension

Dermatologic Effects

• Photosensitivity
• Rash
• Urticaria

Endocrine/Metabolic Effects

• Hypoalbuminemia
• Increased body temperature

Gastrointestinal Effects

• Abdominal pain
• Diarrhea
• Loss of appetite
• Nausea
• Vomiting

Hematologic Effects

• Leukopenia

Hepatic Effects

• Hepatitis
• Increased liver enzymes

Immunologic Effects

• Anaphylaxis
• Jarisch-Herxheimer reaction

Neurologic Effects

• Dizziness
• Headache

Respiratory Effects

• Cough
• Respiratory distress
• Tachypnea
• Wheezing

Other

• Angioedema

Therapeutic Uses

• Infection by Fasciola (non-FDA approval)
• Infection by Paragonimus (non-FDA approval)

Mechanism of Action

Bithionol is a chlorinated phenol derivative which has antimicrobial and anthelmintic activity by uncoupling oxidative phosphorylation in the parasite, leading to blockade of adenosine triphosphate synthesis and energy production.