Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
ERGAMISOL vs EMVERM
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Levamisole is an anthelmintic and immunomodulator. It acts as a nicotinic acetylcholine receptor agonist at the neuromuscular junction in nematodes, causing spastic paralysis. Its immunomodulatory effects are thought to involve stimulation of T-cell activation and phagocytosis.
Mebendazole binds to tubulin, inhibiting microtubule polymerization, which disrupts glucose uptake and causes energy depletion leading to parasite death.
Adjuvant therapy in combination with fluorouracil for the treatment of Dukes' C colon cancer (FDA-approved, now discontinued),Off-label: treatment of steroid-resistant nephrotic syndrome in children, and as an adjuvant in melanoma and other cancers
Treatment of trichuriasis (whipworm infection),Treatment of enterobiasis (pinworm infection),Treatment of ascariasis (roundworm infection),Treatment of hookworm infections (Ancylostoma duodenale and Necator americanus),Off-label: Treatment of capillariasis, toxocariasis, and other helminth infections
150 mg orally once daily
Mebendazole 100 mg orally twice daily for 3 days for adults and children over 2 years.
2-4 hours (terminal); prolonged in hepatic impairment (up to 8-12 hours) and renal impairment (increase by 1.5- to 2-fold).
2-8 hours; clinical context: the short half-life supports once-daily dosing; metabolites may persist longer.
Hepatic metabolism primarily via CYP450 enzymes (CYP2B6 and CYP3A4) to active metabolites. Levamisole undergoes extensive biotransformation to its major metabolites, p-hydroxy-levamisole and levamisole sulfoxide.
Primarily hepatic; metabolized by microsomal enzymes (CYP450) to major metabolite 2-aminomebendazole, which is less active; also undergoes further metabolism.
Renal (parent drug and metabolites): ~70% in urine; Fecal: ~25% primarily as metabolites; <5% unchanged in urine.
Primarily fecal (approx. 90%) as unchanged drug and metabolites; <10% excreted renally.
20-30%, primarily to albumin.
~90-95% bound to plasma proteins, primarily albumin.
1.0-1.5 L/kg; indicates extensive tissue distribution, including penetration into liver and kidneys.
~1-2 L/kg; indicates extensive tissue distribution.
Oral: 40-60% (extensive first-pass metabolism).
Oral: ~22-40% due to first-pass metabolism; improved with food.
GFR 30-60 m L/min: no adjustment; GFR <30 m L/min: not recommended
No adjustment required for mild to moderate renal impairment. Not studied in severe renal impairment (Cr Cl <30 m L/min); use with caution.
Child-Pugh A: no adjustment; Child-Pugh B or C: avoid use
No adjustment for mild (Child-Pugh A) or moderate (Child-Pugh B) impairment. Avoid use in severe hepatic impairment (Child-Pugh C) due to increased risk of toxicity.
2.5 mg/kg orally once daily; maximum 150 mg daily
Children ≥2 years: 100 mg orally twice daily for 3 days. Children <2 years: safety not established; use only if potential benefit outweighs risk.
No specific adjustment; monitor for renal function and potential QT prolongation
No specific adjustment required; use standard adult dosing. Monitor for adverse effects due to potential age-related renal or hepatic decline.
None specifically required for ergamisol (levamisole). However, use of levamisole as an immunomodulator has been associated with agranulocytosis and other severe hematologic reactions.
None.
Agranulocytosis (may occur weeks after initiation and is reversible upon discontinuation), hemolytic anemia (especially in patients with G6PD deficiency), neurologic effects (seizures, dizziness, headache), hepatotoxicity, and hypersensitivity reactions.
Risk of neutropenia and agranulocytosis, especially with high doses or prolonged use,May cause bone marrow suppression; monitor blood counts in prolonged therapy,Hepatotoxicity reported; use caution in hepatic impairment,Seizures have occurred, particularly in patients with history of seizures,Not recommended in pregnancy (pregnancy category C); embryotoxic and teratogenic in animals
Known hypersensitivity to levamisole; patients with a history of agranulocytosis induced by levamisole; concomitant use with alcohol (disulfiram-like reaction); caution in patients with hepatic or renal impairment.
Hypersensitivity to mebendazole or any component of the formulation,Absolute contraindication: Known hypersensitivity
Avoid alcohol during therapy due to potential disulfiram-like reaction (nausea, vomiting, flushing). No specific food restrictions; maintain adequate hydration. Grapefruit juice may inhibit CYP2C19 metabolism, potentially increasing levamisole levels; consider avoidance.
No significant food interactions; absorption is enhanced by fatty foods but not required for efficacy in enterobiasis. Avoid alcohol due to potential hepatotoxicity.
Ergamisole (levamisole) is classified as FDA Pregnancy Category C. Animal studies have shown embryotoxicity and teratogenicity at doses comparable to human doses. There are no adequate and well-controlled studies in pregnant women. Use only if potential benefit justifies potential risk to fetus. In first trimester, avoid use; second and third trimester, use with caution if indicated.
FDA Pregnancy Category C. Animal studies have shown embryotoxicity and teratogenicity at high doses. Human data are limited; therefore, use during pregnancy only if clearly needed. Risk cannot be ruled out, especially in the first trimester.
Levamisole is excreted in human milk in low amounts; M/P ratio is not established. Because of potential for serious adverse reactions in nursing infants, a decision should be made whether to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother.
Excretion in human milk unknown. Caution should be exercised when administered to a nursing woman. M/P ratio not available.
Pharmacokinetics in pregnancy are not well characterized. No specific dose adjustments are recommended; however, due to potential for altered metabolism, use lowest effective dose and monitor maternal toxicity closely.
No dose adjustment is recommended solely due to pregnancy, as pharmacokinetic changes are not well characterized. Use standard dosing: mebendazole 100 mg twice daily for 3 days for pinworm (or single 100 mg dose). For other indications, follow standard protocols.
Levamisole (ERGAMISOL) is primarily used as an immunomodulator in adjuvant therapy for stage III colon cancer after surgical resection. It is often combined with fluorouracil. Monitor for agranulocytosis, especially in patients with poor metabolizer status of CYP2D6. Agranulocytosis can occur weeks to months after initiation; obtain baseline CBC and repeat periodically. Levamisole can cause a metallic taste and reversible ANCA-positive vasculitis. Avoid in patients with known hypersensitivity or bone marrow depression.
EMVERM (mebendazole) is poorly absorbed systemically, making it ideal for intraluminal helminth infections. Administer with fatty meal to enhance absorption when systemic effect (e.g., for trichinosis) is desired. Avoid in pregnancy (FDA Category C). Tablets may be chewed, swallowed, or crushed. Monitor for rare agranulocytosis, especially with concurrent metronidazole or high doses.
Take levamisole exactly as prescribed, usually for 3 days every 2 weeks for 1 year. Do not miss doses.,Report any signs of infection (fever, sore throat, mouth sores) immediately as it can lower white blood cell count.,You may experience a metallic taste; this is harmless and may resolve with time.,Avoid alcohol consumption as it may increase risk of adverse effects.,Inform your doctor if you are pregnant, planning to become pregnant, or breastfeeding.,Do not take any other medications or supplements without consulting your doctor.
Take exactly as prescribed; a second course may be needed if reinfection occurs.,Tablets can be chewed, crushed, or swallowed whole with or without food.,Mebendazole works by preventing worms from absorbing sugar, causing their death.,Strict hand hygiene and laundering of bedding/clothing to prevent reinfection.,Treat all household members if pinworm outbreak; withhold treatment in pregnancy unless essential.,Notify provider if fever, sore throat, or unusual bleeding/bruising (agranulocytosis warning).
No interactions on record
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about ERGAMISOL vs EMVERM, answered by our medical review team.
ERGAMISOL is a Anthelmintic Immunomodulator that works by Levamisole is an anthelmintic and immunomodulator. It acts as a nicotinic acetylcholine receptor agonist at the neuromuscular junction in nematodes, causing spastic paralysis. Its immunomodulatory effects are thought to involve stimulation of T-cell activation and phagocytosis.. EMVERM is a Anthelmintic that works by Mebendazole binds to tubulin, inhibiting microtubule polymerization, which disrupts glucose uptake and causes energy depletion leading to parasite death.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between ERGAMISOL and EMVERM depend on the specific clinical indication. These are agents from distinct pharmacological classes and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of ERGAMISOL is: 150 mg orally once daily. The standard adult dose of EMVERM is: Mebendazole 100 mg orally twice daily for 3 days for adults and children over 2 years.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between ERGAMISOL and EMVERM in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. ERGAMISOL is classified as Category C. Ergamisole (levamisole) is classified as FDA Pregnancy Category C. Animal studies have shown embryotoxicity and teratogenicity at doses comparable to human doses. There are no adeq. EMVERM is classified as Category C. FDA Pregnancy Category C. Animal studies have shown embryotoxicity and teratogenicity at high doses. Human data are limited; therefore, use during pregnancy only if clearly needed.. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.