Dose-Dependent Intestinal Absorption and Significant Intestinal Excretion (Exsorption) of the β-Blocker Pafenolol in the Rat

@article{Lennerns2004DoseDependentIA,
  title={Dose-Dependent Intestinal Absorption and Significant Intestinal Excretion (Exsorption) of the $\beta$-Blocker Pafenolol in the Rat},
  author={Hans Lennern{\"a}s and Carl Gunnar Reg{\aa}rdh},
  journal={Pharmaceutical Research},
  year={2004},
  volume={10},
  pages={727-731}
}
The elimination of [3H]pafenolol and metabolites was investigated in fasted and fed rats. Separate groups received intravenous doses (0.3 and 3.0 µmol/kg) and oral doses (1 and 25 µmol/kg). After iv administration of pafenolol, the excretion of unchanged drug into urine and feces was about 50 and 25–30% of the given dose, respectively. The predominating mechanism for the excretion of pafenolol into feces was intestinal excretion (exsorption) directly from blood into gut lumen, since only about… 
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