Herb-Drug Interaction of Paullinia cupana (Guarana) Seed Extract on the Pharmacokinetics of Amiodarone in Rats

Table 2

Pharmacokinetic parameters estimated by noncompartmental analysis of the plasma concentration-time profiles of amiodarone (AM) and mono-N-desethylamiodarone (MDEA, major metabolite of AM) obtained in rats submitted to a 14-day pretreatment period with Paullinia cupana extract (821 mg/kg/day, p.o.), or vehicle (0.5% carboxymethylcellulose aqueous solution), and treated on the 15th day with a single dose of AM (50 mg/kg, p.o.) by oral gavage (𝑛=6, unless otherwise noted).

Parameter	AMPaullinia		AMVehicle
	AM	MDEA	AM	MDEA
𝑡max (h)	1.50 ± 0.22	2.00 ± 0.00^a	2.00 ± 0.63	9.00 ± 2.12^b
𝐶max (𝜇g/mL)	1.483 ± 0.203	0.112 ± 0.00^a	1.046 ± 0.151	0.106 ± 0.004^b
AUC0–t (𝜇g·h/mL)	13.422 ± 1.266	ND	12.282 ± 1.047	ND
AUC0–∞ (𝜇g·h/mL)	23.489 ± 1.970	ND	22.057 ± 2.905	ND
𝐾el (h^−1)	0.0416 ± 0.0079	ND	0.0442 ± 0.0108	ND
𝑡1/2el (h)	23.07 ± 7.58	ND	21.62 ± 5.85	ND
MRT (h)	32.65 ± 10.41	ND	31.02 ± 8.29	ND

ND: not determined.
^a𝑛 = 1; ^b𝑛 = 4.