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Published on: March 28, 2017
Pharmacokinetic studies with 3H-cytisine
Archives of Toxicology. Supplement. = Archiv Fur Toxikologie. Supplement
|January 1, 1980
Summary
Cytisine absorption and elimination were studied in mice. Oral cytisine reached peak blood levels in 2 hours with 42% absorption, and the drug concentrated in the liver, adrenals, and kidneys.
Area of Science:
- Pharmacology
- Drug Metabolism
- Toxicology
Background:
- Cytisine is a natural alkaloid with potential therapeutic applications.
- Understanding its pharmacokinetic profile is crucial for safe and effective use.
Purpose of the Study:
- To investigate the pharmacokinetic behavior of cytisine in mice.
- To determine absorption, distribution, metabolism, and excretion (ADME) parameters.
Main Methods:
- Tritiated cytisine was administered intravenously and orally to mice at a dose of 2 mg/kg.
- Blood, urine, feces, bile, and tissue concentrations were measured over time.
Main Results:
- Oral absorption reached maximum blood levels within 2 hours, with an absorption rate of approximately 42%.
- The calculated half-life after intravenous administration was 200 minutes.
- Excretion occurred primarily via urine (32% IV, 18% oral within 24h) and feces (3% IV within 6h).
- Highest tissue concentrations were observed in the liver, adrenals, and kidneys. Bile concentrations were significantly higher than blood concentrations (200x).
Conclusions:
- Cytisine exhibits moderate oral absorption and a relatively long half-life in mice.
- The drug distributes to key organs and is eliminated through both renal and fecal routes.
- These findings provide essential data for further preclinical and clinical development of cytisine.
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