• DOI:10.1002/cpt1974152178
• Corpus ID: 74223978

Pharmacokinetics of orally administered furosemide

@article{Michael1974PharmacokineticsOO,
  title={Pharmacokinetics of orally administered furosemide},
  author={Ronald Michael and Erik C. Ralph and W. Forrey Arden and M. Barbara},
  journal={Clinical Pharmacology \& Therapeutics},
  year={1974},
  volume={15}
}

• R. Michael, E. C. Ralph, +1 author M. Barbara
• Published 1 February 1974
• Medicine
• Clinical Pharmacology & Therapeutics

Furosemide (80 mg) as tablets or aqueous solution was taken orally by normal subjects during a fast and postprandially. Comparative studies were obtained using intravenous furosemide and 35S‐furosemide. No significant differences were apparent between tablets and aqueous solution. During fasting, detectable drug levels appeared in the serum within 10 minutes, peaked (mean 2.2 μg/ml) between 60 and 70 minutes, and decreased to nearly undetectable levels between 3 and 4 hours after ingestion. The postprandial studies displayed delayed appearance and low‐peak serum concentrations (mean 1.0 μg/ml), with only a slight decrease in concentration at the end of 4 hours. However, the total amount of drug absorbed was similar, and about 60% of the drug was calculated to be absorbed during fasting. The 24‐hour excretion of 35S‐furosemide was between 30% and 50% of the administered dose. The diuresis observed in each study over a 12 hour period was not Significantly different between dosage forms as well as whether given during a fast or postprandially. Extracellular volume appeared to be the most critical factor in determining diuretic response. It is concluded that the availability of orally administered furosemide is similar regardless of the dosage form and meals, and that the diuretic response is similar to that to a comparable parenteral dose.