Rat single-dose PK (validated UPLC-MS/MS; Sprague–Dawley)
Dose: 2.5 mg/kg i.v.; 20 mg/kg p.o.
Vz (i.v.): 6.2 ± 2.3 L/kg
CL: 0.7 ± 0.2 L/h/kg
Absolute oral bioavailability (F): 20.7%
(Non-compartmental analysis from plasma concentration–time.)
From CL/Vz, kₑ ≈ 0.113 h⁻¹ → t½ ≈ 6.1 h (derived).
Human exposure (kratom product; healthy volunteers)
Following a kratom product orally,
speciociliatine was the major circulating alkaloid with
AUC₀-inf ≈ 5120 nM·h, about
12× mitragynine
(AUC₀-inf ≈ 420 nM·h), despite ~4× lower content of speciociliatine than mitragynine in the product. PMC
Interpretation for readers
The high circulating exposure suggests speciociliatine may disproportionately contribute to kratom’s systemic pharmacology compared with its label content; emphasize that these data reflect one product/setting and may vary by formulation and metabolism.
