Benznidazole
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From MedlinePlus, U.S. National Library of Medicine
Dosing in kidney impairment
Renal Impairment Use of Benznidazole Tablets has not been evaluated in patients with renal impairment.
Dosing in liver impairment
Hepatic Impairment Use of Benznidazole Tablets has not been evaluated in patients with hepatic impairment.
Preparation and administration
Important Administration Instructions Benznidazole Tablets (12.5 mg and 100 mg) are for oral use and may be taken with or without food [see Clinical Pharmacology] . Benznidazole Tablets are dosed by body weight (kg) [see Dosage and Administration] . Benznidazole Tablets 100 mg are functionally scored tablets which can be split into one-half (50 mg) or one-quarter (25 mg) at the scored lines to provide doses less than 100 mg [see Instructions for Use ] .
Benznidazole Tablets 12.5 mg and 100 mg can be made into slurry as an alternative method of administration [see Dosage and Administration] .
Preparation of Slurry as an Alternative Method of Administration A. Preparation of Slurry Using Benznidazole Tablets 12.5 mg for the Pediatric Population with Body Weight Less Than 30 kg Benznidazole Tablets 12.5 mg may be made into slurry in a specified volume of water for the pediatric population with body weight less than 30 kg (see Table 2 ).
The 12.5 mg tablet slurry is prepared by the following method: [See table below.] B. Preparation of Slurry Using Benznidazole Tablets 100 mg for the Pediatric Population with Body Weight (30 kg or greater) Benznidazole Tablets 100 mg may be made into a slurry in a specified volume of water for the pediatric population with body weight of 30 kg or greater (see Table 3 ).
The 100 mg tablet slurry is prepared as follows: [See table below.]
| Place the prescribed dose of Benznidazole Tablets 12.5 mg into a cup.Add the specified volume of water per number of 12.5 mg tablets as shown below. | |||
| Body Weight Range (kg) | Dose (mg) | Number of Benznidazole Tablets 12.5 mg | Quantity of Water for Preparing the Slurry |
| Less than 15 kg | 50 mg | 4 tablets | 40 mL |
| 15 kg to less than 20 kg | 62.5 mg | 5 tablets | 50 mL |
| 20 kg to less than 30 kg | 75 mg | 6 tablets | 60 mL |
| Allow the tablets to disintegrate in the cup over a period of approximately 1-2 minutes.Shake the contents of the cup gently to mix.Drink the contents of the cup (slurry of tablets with water) immediately.Rinse the cup with an additional 10 mL of water and drink the whole amount. | |||
| Place the prescribed dose of Benznidazole Tablets 100 mg tablets into a cup.Add the specified volume of water per number of 100 mg tablets as shown below. | |||
| Body Weight Range (kg) | Dose (mg) | Number of Benznidazole Tablets 100 mg | Quantity of Water for Preparing the Slurry |
| 30 kg to less than 40 kg | 100 mg | 1 tablet | 80 mL |
| 40 kg to less than 60 kg | 150 mg | 1 ½ tablets | 120 mL |
| Greater than or equal to 60 kg | 200 mg | 2 tablets | 160 mL |
| Allow the tablet(s) to disintegrate in the cup over a period of approximately 1- 2 minutes.Shake the contents of the cup gently to mix.Drink the contents of the cup (slurry of tablet(s) with water) immediately.Rinse the cup by adding 80 mL of water and drink the whole amount. Repeat this rinse with 80 mL of water and drink again. | |||
Drug interactions
Check benznidazole against a medication listLabel text (3 paragraphs)
7 DRUG INTERACTIONS
7.1 Disulfiram Psychotic reactions have been reported in patients who are concurrently taking disulfiram and nitroimidazole agents (structurally related to benznidazole, but not with benznidazole). Benznidazole Tablets should not be given to patients who have taken disulfiram within the last two weeks [see Contraindications ( 4.2 )] .
7.2 Alcohol and Products Containing Propylene Glycol In vitro studies showed that benznidazole, at concentrations from 0.03 μM to 100 μM, does not inhibit the enzymatic activity of human alcohol dehydrogenase (ALDH). Benznidazole Tablets are not expected to cause alcohol aversion or a disulfiram-like reaction as a result of ethanol ingestion.
Contraindications
4 CONTRAINDICATIONS • History of hypersensitivity reaction to benznidazole or other nitroimidazole derivatives ( 4.1 ). • Disulfiram usage within the last two weeks ( 4.2 ). • Patients with Cockayne Syndrome ( 4.3 , 6.2 ).
4.1 Hypersensitivity Benznidazole Tablets are contraindicated in patients with a history of hypersensitivity reaction to benznidazole or other nitroimidazole derivatives. Reactions have included severe skin and soft tissue reactions [see Adverse Reactions ( 6.1 )] .
4.2 Disulfiram Benznidazole Tablets are contraindicated in patients who have taken disulfiram within the last two weeks. Psychotic reactions may occur in patients who are using benznidazole and disulfiram concurrently [see Drug Interactions ( 7.1 )] .
4.3 Patients with Cockayne Syndrome Benznidazole Tablets are contraindicated in patients with Cockayne syndrome. Severe irreversible hepatotoxicity/acute liver failure with fatal outcomes have been reported after initiation of metronidazole, another nitroimidazole drug, structurally related to benznidazole in patients with Cockayne syndrome [see Adverse Reactions ( 6.2 )] .
Pregnancy and lactation
Pregnancy
8.1 Pregnancy Risk Summary Based on findings from animal studies, Benznidazole Tablets may cause fetal harm when administered to a pregnant woman. Published postmarketing reports on benznidazole use during pregnancy are insufficient to inform a drug-associated risk of adverse pregnancy-related outcomes. There are risks to the fetus associated with Chagas Disease (see Clinical Considerations ) .
In embryo-fetal development studies, benznidazole administered orally to pregnant rats and rabbits during organogenesis was associated with fetal malformations at doses approximately 1-3 times the MRHD in rats (anasarca, anophthalmia, and/or microphthalmia) and doses approximately 0.3-1.0 times the MRHD in rabbits (ventricular septal defect). In pregnant rats administered benznidazole during gestation and through lactation, effects in first generation offspring included reduced fertility in individual males and reduced numbers of live embryos and fetuses in pregnant females at a maternal dose equivalent to approximately 1.5 times the MRHD (see Data ) .
Advise pregnant women of the potential risk to a fetus. The estimated background risk of major birth defects and miscarriage for the indicated population is 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. Clinical Considerations Disease-associated Maternal and/or Embryo/Fetal Risk Published data from case-control and observational studies on chronic Chagas disease during pregnancy are inconsistent in their findings.
Some studies showed an increased risk of pregnancy loss, prematurity and neonatal mortality in pregnant women who have chronic Chagas disease while other studies did not demonstrate these findings. Chronic Chagas disease is usually not life-threatening. Since pregnancy findings are inconsistent, treatment of chronic Chagas disease during pregnancy is not recommended due to risk of embryo-fetal toxicity from Benznidazole Tablets. Acute symptomatic Chagas disease is rare in pregnant women; however, symptoms may be serious or life-threatening. There have been reports of pregnant women with life-threatening symptoms associated with acute Chagas disease who were treated with benznidazole.
If a pregnant woman presents with acute symptomatic Chagas disease, the risks versus benefits of treatment with Benznidazole Tablets to the mother and the fetus should be evaluated on a case-by-case…
For breastfeeding, also see LactMed (National Library of Medicine), which summarizes milk levels and infant effects.
Supply and cost
Drug shortage status
Recalls (last 24 months)
Therapeutic equivalence (Orange Book)
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