Pharmacokinetic and Pharmacodynamic Interactions between Green Tea Extract and Alprazolam in Wistar Rats
Darshan Gowda B.S., Sunil Kumar KadiriIntroduction::
Alprazolam, a short-acting triazolobenzodiazepine frequently used for anxiety disorders, is predominantly metabolized by Cytochrome P450 3A4 (CYP3A4). Green tea (Camellia sinensis), rich in catechins, has demonstrated the ability to inhibit CYP3A4 and may involve additive CNS depressant mechanisms, potentially affecting the pharmacological characteristics of concurrently taken drugs. This research examined the pharmacokinetic and pharmacodynamic interactions of green tea extract and alprazolam in albino Wistar rats.
Methods::
Animals were divided into four groups (n = 6): control, green tea, alprazolam, and alprazolam combined with green tea, and oral treatments for a duration of 30 days. Behavioral evaluations included the Y-maze, Morris water maze, rotarod, and actophotometer. Biochemical assessments of Acetylcholinesterase (AChE) and Superoxide Dismutase (SOD) activity were performed, in conjunction with histological examination of neuronal morphology. Pharmacokinetics was assessed using non-compartmental analysis utilizing HPLC.
Results::
The concurrent treatment of green tea extract and alprazolam markedly decreased locomotor activity, motor coordination, and memory, while simultaneously decreasing Superoxide Dismutase (SOD) levels and increasing Acetylcholinesterase (AChE) activity, suggesting oxidative stress and cholinergic dysfunction.
Discussion::
Pharmacokinetic study indicated elevated Cmax and AUC, prolonged half-life, and reduced clearance of alprazolam, possibly associated with interference in CYP3A-mediated metabolism. Histopathological analysis revealed significant neuronal degeneration in the combination group.
Conclusion::
These data highlight a significant herb–drug interaction, indicating the need for caution when concurrently using green tea and alprazolam due to increased sedative and cognitive adverse effects.