Pharmacokinetics of levamisole.

Area of Science:

• Pharmacology
• Veterinary Medicine
• Toxicology

Background:

• Levamisole is an anthelmintic and immunomodulatory drug used in both veterinary and human medicine.
• Understanding its absorption, distribution, metabolism, and excretion (ADME) is crucial for safe and effective use.

Purpose of the Study:

• To characterize the pharmacokinetic profile of levamisole in various animal species and humans.
• To determine the routes and rates of excretion for levamisole and its metabolites.

Main Methods:

• Administration of levamisole via oral, intramuscular, and subcutaneous routes in animal models.
• Analysis of plasma, urine, and fecal samples to quantify drug and metabolite concentrations.
• Bioequivalence study comparing levamisole syrup and tablets in humans.

Main Results:

• Rapid absorption of levamisole across different administration routes and species.
• Extensive metabolism of levamisole, with unchanged drug being a minor component in plasma and excreta.
• Predominant excretion of radioactivity in urine (60%) and feces (4%) within 24 hours in rats.
• Peak plasma levamisole levels of 0.5 microgram/ml reached in humans 2-4 hours post-dose.
• Demonstrated bioequivalence between levamisole syrup and tablets.

Conclusions:

• Levamisole exhibits rapid absorption and extensive metabolism, leading to quick elimination.
• Urinary excretion is the primary route for levamisole and its metabolites.
• Levamisole syrup and tablets are bioequivalent, offering interchangeable dosage forms.