Drug Reference
Mebendazole
Benzimidazole derivatives
Rx only
Fact box
- Therapeutic class
- Benzimidazole derivatives
- Action class
- Anthelmintic
- Habit forming
- No
- Availability
- Prescription (Rx)
Brand names
EmvermVermox
Available as
100 MG · Chewable Tablet500 MG · Chewable Tablet20 MG/ML · Oral Suspension100 MG · Oral Tablet
FDA label sections are from openFDA and may not reflect the most recent labeling — confirm against the current DailyMed label.
Uses
1 INDICATIONS AND USAGE VERMOX™ CHEWABLE is indicated for the treatment of patients one year of age and older with gastrointestinal infections caused by Ascaris lumbricoides (roundworm) and Trichuris trichiura (whipworm). VERMOX™ CHEWABLE is an anthelmintic indicated for the treatment of patients one year of age and older with gastrointestinal infections caused by: Ascaris lumbricoides (roundworm) and Trichuris trichiura (whipworm) ( 1 ).
How it works
12.1 Mechanism of Action Mebendazole, a benzimidazole, is an anthelmintic [see Microbiology (12.4) ] .
How to use / dosing
2 DOSAGE AND ADMINISTRATION The recommended dosage in patients one year of age and older is one VERMOX™ CHEWABLE 500 mg tablet taken as a single dose. Chew VERMOX™ CHEWABLE 500 mg tablet completely before swallowing. Do not swallow the tablet whole. For patients who have difficulty chewing the tablet, approximately 2 mL to 3 mL of drinking water can be added to a suitably sized spoon and the VERMOX™ CHEWABLE 500 mg tablet placed into the water. Within 2 minutes, the tablet absorbs the water and turns into a soft mass with semi-solid consistency, which can then be swallowed. VERMOX™ CHEWABLE 500 mg tablet can be taken without regard to food intake [see Clinical Pharmacology (12.3) ]. The recommended dosage in patients one year of age and older is one single tablet of VERMOX™ CHEWABLE 500 mg taken as a single dose, chewed completely before swallowing ( 2 ). See Full Prescribing Information for administration instructions for patients who have difficulty chewing the tablets ( 2 )
Side effects
6 ADVERSE REACTIONS Adverse reactions reported in clinical trials were anorexia, abdominal pain, diarrhea, flatulence, nausea, vomiting and rash. ( 6.1 ). To report SUSPECTED ADVERSE REACTIONS, contact Janssen Pharmaceuticals, Inc. at 1-800-JANSSEN (1-800-526-7736) or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Studies Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. The safety of mebendazole was evaluated in 6276 adult and pediatric subjects one year of age and older who participated in 39 clinical trials for treatment of single or mixed parasitic infections of the gastrointestinal tract. In these trials, the formulations, dosages and duration of mebendazole treatment varied. Adverse reactions reported in mebendazole-treated subjects from the 39 clinical trials are shown in Table 1 below. Table 1: Adverse Reactions Reported in Mebendazole-Treated Subjects from 39 Clinical Trials Includes mebendazole formulations, dosages and treatment duration other than VERMOX™ CHEWABLE 500 mg tablet Adverse Reaction(s) Gastrointestinal Disorders Anorexia Abdominal Pain Diarrhea Flatulence Nausea Vomiting Skin and Subcutaneous Tissue Disorders Rash Clinical Studies with Mebendazole Chewable 500 mg Tablet The safety profile of mebendazole chewable 500 mg tablets administered as a single dose was evaluated in 677 pediatric subjects aged 1 to 16 years and in 34 adults. The safety profile was consistent with the known safety profile of mebendazole. 6.2 Postmarketing Experience The following adverse reactions have been identified in adult and pediatric patients postmarketing with mebendazole formulations and dosages other than the VERMOX™ CHEWABLE 500 mg tablet. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Table 2: Adverse Reactions Identified During Postmarketing Experience with Mebendazole Includes mebendazole formulations, dosages and treatment durations other than VERMOX™ CHEWABLE 500 mg tablet Adverse Reaction(s) Blood and Lymphatic System Disorders Agranulocytosis, Neutropenia Immune System Disorders Hypersensitivity including anaphylactic reactions Nervous System Disorders Convulsions, Dizziness Hepatobiliary Disorders Hepatitis, Abnormal liver tests Renal and Urinary Disorders Glomerulonephritis Skin and Subcutaneous Tissue Disorders Toxic epidermal necrolysis, Stevens-Johnson syndrome, Exanthema, Angioedema, Urticaria, Alopecia
Safety advice
Conservative summary derived from FDA labeling — defaults to “consult your doctor” unless the label is explicit. Not a substitute for your clinician’s advice.
PregnancyUnsafe
8.1 Pregnancy Risk Summary The available published literature on mebendazole use in pregnant women has not reported a clear association between mebendazole and a potential risk of major birth defects or miscarriages [see Data ]. There are risks to the mother and fetus associated with untreated helminthic infection during pregnancy [see Clinical Considerations ] . In animal reproduction studies, adverse developmental effects (i.e., skeletal malformations, soft tissue malformations, decreased pup weight, embryolethality) were observed when mebendazole was administered to pregnant rats during the period of organogenesis at single oral doses as low as 10 mg/kg (approximately 0.2-fold the maximum recommended human dose (MRHD)). Maternal toxicity was present at the highest of these doses [see Data ]. The estimated background risk of major birth defects and miscarriage for the indicated populations 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 2–4% and 15–20%, respectively. Clinical Considerations Disease-Associated Maternal and/or Embryo/Fetal Risks Untreated soil-transmitted helminth infections in pregnancy are associated with adverse outcomes including maternal iron deficiency anemia, low birth weight, neonatal and maternal death. Data Human Data Several published studies, including prospective pregnancy registries, case-control, retrospective cohort, and randomized controlled studies, have reported no association between mebendazole use and a potential risk of major birth defects or miscarriage. Overall, these studies did not identify a specific pattern or frequency of major birth defects with mebendazole use. However, these studies cannot definitely establish the absence of any mebendazole-associated risk because of methodological limitations, including recall bias, confounding factors and, in some cases, small sample size or exclusion of first trimester mebendazole exposures. Animal Data Embryo-fetal developmental toxicity studies in rats revealed no adverse effects on dams or their progeny at doses up to 2.5 mg/kg/day on gestation days 6–15 (the period of organogenesis). Dosing at ≥10 mg/kg/day resulted in a lowered body weight gain and a decreased pregnancy rate. Maternal toxicity, including body weight loss in one animal and maternal death in 11 of 20 animals, w
BreastfeedingConsult your doctor
…8.2 Lactation Risk Summary Limited data from case reports demonstrate that a small amount of mebendazole is…
AlcoholNo information
No specific information in the FDA label.
DrivingNo information
No specific information in the FDA label.
KidneyNo information
No specific information in the FDA label.
LiverNo information
No specific information in the FDA label.
Warnings & precautions
5 WARNINGS AND PRECAUTIONS Risk of Convulsions: Convulsions in infants below the age of 1 year have been reported ( 5.1 ) Hematologic Effects: Neutropenia and agranulocytosis have been reported in patients receiving mebendazole at higher doses and for prolonged duration. Monitor blood counts in these patients ( 5.2 ) Metronidazole and Serious Skin Reactions: Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) have been reported with the concomitant use of mebendazole and metronidazole. Avoid concomitant use of mebendazole and metronidazole ( 5.3 ) 5.1 Risk of Convulsions Convulsions have been reported in infants below the age of 1 year during post-marketing experience with mebendazole [see Adverse Reactions (6.2) ] . 5.2 Hematologic Effects Agranulocytosis and neutropenia have been reported with mebendazole use at higher doses and for more prolonged durations than is recommended for the treatment of soil-transmitted helminth infections. Monitor blood counts if VERMOX™ CHEWABLE is used at higher doses or for prolonged duration. 5.3 Metronidazole Drug Interaction and Serious Skin Reactions Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) have been reported with the concomitant use of mebendazole and metronidazole. Avoid concomitant use of mebendazole and metronidazole.
Contraindications
4 CONTRAINDICATIONS VERMOX™ CHEWABLE is contraindicated in persons with a known hypersensitivity to the drug or its excipients. Patients with a known hypersensitivity to the drug or its excipients ( 4 )
Pediatric use
8.4 Pediatric Use The safety and effectiveness of VERMOX™ CHEWABLE 500 mg tablets have been established in pediatric patients 1 to 16 years of age. Use of VERMOX™ CHEWABLE 500 mg tablets in children is supported by evidence from adequate and well-controlled studies of VERMOX™ CHEWABLE 500 mg tablets [see Clinical Studies (14) ] . The safety and effectiveness of mebendazole, including VERMOX™ CHEWABLE have not been established in pediatric patients less than one year of age. Convulsions have been reported with mebendazole use in this age group [see Warnings and Precautions (5.1) and Adverse Reactions (6.2) ].
⚑ About half of pediatric medication use is off-label and not described in FDA labels — absence of pediatric information does not mean a medicine is unused or unsafe in children. Confirm with your clinician.
Interactions (label text — not an interaction checker)
7 DRUG INTERACTIONS Concomitant use of mebendazole and metronidazole should be avoided [see Warnings and Precautions (5.3) ] .
Overdose
10 OVERDOSAGE In patients treated at dosages substantially higher than recommended or for prolonged periods of time, the following adverse reactions have been reported: alopecia, reversible transaminase elevations, hepatitis, agranulocytosis, neutropenia, and glomerulonephritis. Symptoms and signs In the event of accidental overdose, gastrointestinal signs/symptoms may occur. Treatment There is no specific antidote.
Current FDA labels (DailyMed)
Authoritative sources
Reference only — not clinical advice. Verify against current FDA labeling and consult a licensed provider. About half of pediatric drug use is off-label and is not reflected in FDA labels; absence of pediatric information does not mean a medicine is unused or unsafe in children.