Usage
Levamisole + Mebendazole is a combination anthelmintic medication primarily used to treat various parasitic worm infections, including:
- Ascariasis: Infection with the roundworm Ascaris lumbricoides.
- Hookworm infection: Infection with hookworms like Ancylostoma duodenale or Necator americanus.
- Trichuriasis (Whipworm infection): Infection with the whipworm Trichuris trichiura.
- Enterobiasis (Pinworm infection): Infection with the pinworm Enterobius vermicularis.
Pharmacological Classification: Anthelmintic
Mechanism of Action: Levamisole acts as a nicotinic acetylcholine receptor agonist, causing spastic paralysis in susceptible worms. Mebendazole inhibits tubulin polymerization in worms, disrupting glucose uptake and leading to their death. The combination of these two drugs with different mechanisms of action can enhance efficacy against a broader range of parasitic worms.
Alternate Names
There are no widely recognized alternate names for this specific combination. However, the individual components are sometimes referred to as:
- Levamisole: Ergamisol
- Mebendazole: Vermox
How It Works
Pharmacodynamics: Levamisole stimulates nicotinic acetylcholine receptors at the neuromuscular junction of susceptible helminths, leading to spastic paralysis. Mebendazole selectively inhibits microtubule synthesis in intestinal worms, blocking glucose uptake and depleting glycogen stores, ultimately causing their death.
Pharmacokinetics:
- Levamisole: Rapidly absorbed from the gastrointestinal tract, reaching peak plasma concentrations within 1.5-4 hours. Metabolized primarily in the liver and excreted mainly in urine.
- Mebendazole: Poorly absorbed from the GI tract. Systemic absorption is increased with fatty meals. Metabolized extensively in the liver and excreted primarily in feces.
Mode of Action: Levamisole acts as a cholinergic agonist, leading to persistent stimulation of nematode muscles and ultimately paralysis. Mebendazole inhibits tubulin polymerization in helminths, causing their death by starvation.
Elimination Pathways:
- Levamisole: Primarily renal excretion.
- Mebendazole: Primarily hepatic metabolism and fecal excretion.
Dosage
Standard Dosage
Special Cases:
- Elderly Patients: Dosage adjustments may be necessary based on renal and hepatic function.
- Patients with Renal Impairment: Caution and potential dosage adjustments are necessary.
- Patients with Hepatic Dysfunction: Dosage adjustments may be required.
- Patients with Comorbid Conditions: Evaluate individual patient needs and consider potential drug interactions.
Clinical Use Cases
The Levamisole/Mebendazole combination is typically not used in the clinical settings you mentioned (intubation, surgical procedures, mechanical ventilation, ICU, emergency situations). It is primarily intended for treating specific parasitic worm infections.
Dosage Adjustments
Dosage adjustments may be necessary based on the severity of infection, patient age, weight, renal function, hepatic function, and other patient-specific factors.
Side Effects
Common Side Effects:
- Nausea, vomiting, abdominal pain, diarrhea
- Dizziness, headache
- Loss of appetite
Rare but Serious Side Effects:
- Agranulocytosis, neutropenia (more likely with prolonged or high-dose mebendazole)
- Allergic reactions (skin rash, itching, swelling)
- Stevens-Johnson syndrome (rare, more likely with concurrent metronidazole use)
- Liver dysfunction
- Seizures (rare)
Long-Term Effects:
Long-term effects are uncommon with standard dosing. However, chronic high-dose mebendazole has been associated with bone marrow suppression.
Adverse Drug Reactions (ADR): See “Rare but Serious Side Effects.”
Contraindications
- Hypersensitivity to levamisole, mebendazole, or benzimidazole derivatives.
- Pregnancy (especially first trimester for mebendazole).
- Concomitant use of metronidazole with mebendazole.
Drug Interactions
- Cimetidine: May increase mebendazole plasma concentrations.
- Metronidazole: Concurrent use with mebendazole may increase the risk of Stevens-Johnson syndrome and toxic epidermal necrolysis.
- Phenytoin: Levamisole may increase phenytoin levels.
Pregnancy and Breastfeeding
- Pregnancy: Mebendazole is contraindicated during pregnancy, especially in the first trimester. Levamisole should be avoided during pregnancy.
- Breastfeeding: Mebendazole is present in breast milk and should be used with caution. Levamisole use during breastfeeding is generally discouraged.
Drug Profile Summary
- Mechanism of Action: Levamisole: nicotinic acetylcholine receptor agonist causing worm paralysis. Mebendazole: inhibits microtubule formation in worms, disrupting glucose uptake.
- Side Effects: Nausea, vomiting, abdominal pain, diarrhea, dizziness, headache. Rarely: agranulocytosis, allergic reactions, liver dysfunction.
- Contraindications: Hypersensitivity, pregnancy, concomitant metronidazole use with mebendazole.
- Drug Interactions: Cimetidine, metronidazole, phenytoin.
- Pregnancy & Breastfeeding: Contraindicated or use with caution.
- Dosage: Varies depending on infection and patient factors. See detailed section above.
- Monitoring Parameters: Complete blood count (especially with prolonged or high-dose mebendazole), liver function tests.
Popular Combinations
While levamisole and mebendazole are often combined in a single formulation, they are not typically combined with other drugs for the treatment of parasitic infections.
Precautions
- Monitor complete blood count and liver function tests during treatment, especially with prolonged or high-dose use.
- Patients with pre-existing blood disorders or liver disease require careful monitoring.
- In patients with Crohn’s disease or ulcerative colitis, mebendazole should be used with caution.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Levamisole + Mebendazole?
A: Dosage varies based on the specific product, the infection being treated, and patient factors. Consult local guidelines and the product information. A common regimen for adults is a single tablet containing 150mg of Levamisole and 100 mg of Mebendazole, sometimes repeated after a period of two to three weeks. Pediatric dosages should be determined by a physician based on weight or age.
Q2: What are the common side effects?
A: Common side effects include nausea, vomiting, abdominal pain, diarrhea, dizziness, and headache.
Q3: What are the serious side effects?
A: Serious side effects are rare but can include agranulocytosis, neutropenia (especially with high-dose or prolonged mebendazole use), severe allergic reactions, and liver dysfunction.
Q4: Can pregnant women take Levamisole + Mebendazole?
A: No. Mebendazole is contraindicated during pregnancy, especially in the first trimester. Levamisole should also be avoided.
Q5: What are the drug interactions I should be aware of?
A: Significant interactions can occur with cimetidine, metronidazole (with mebendazole), and phenytoin.
Q6: What should I monitor in patients taking this medication?
A: Monitor complete blood count, especially during prolonged or high-dose therapy with mebendazole, and liver function tests.
Q7: Is this drug combination safe for children?
A: Pediatric dosing should be determined by a physician based on weight or age. Mebendazole is generally not recommended for children under 2 years of age.
Q8: What if my patient has renal or hepatic impairment?
A: Dosage adjustments may be necessary. Use with caution and consult local guidelines.
Q9: How is this medication administered?
A: The combination is typically administered orally as a tablet. The tablet can be swallowed whole, chewed, or crushed and mixed with food.
Q10: How long does treatment last?
A: Treatment duration varies depending on the infection being treated. A single dose may be sufficient for some infections, while others require multiple doses over several days. Retreatment may be necessary after a few weeks, especially for pinworm infections.
