title: Randomized, open-label, 5-way crossover study to evaluate the pharmacokinetic/pharmacodynamic interaction between furosemide and the non-steroidal anti-inflammatory drugs diclofenac and ibuprofen in healthy volunteers.
abstract: OBJECTIVE
  Nonsteroidal anti-inflammatory drugs (NSAIDs) can induce renal complications in patients taking loop diuretics. This study investigated the pharmacokinetic/pharmacodynamic effects and safety profile of orally administered diclofenac sodium, ibuprofen and diclofenac epolamine topical patch (DETP) on furosemide in healthy adult subjects.
  
  
  METHODS
  This open-label, randomized, 5-way crossover study was conducted in 40 subjects (aged 19 - 45 y). Diclofenac (75 mg taken orally twice daily), DETP (1.3% applied topically twice daily), or ibuprofen (800 mg taken orally thrice daily) was administered for 3 consecutive days, followed by co-administration with furosemide (given intravenously as 20 mg/2 min). Plasma furosemide and NSAID concentrations, urine furosemide, sodium and potassium concentrations and urine output were determined throughout the 24 h period following furosemide administration.
  
  
  RESULTS
  Orally administered ibuprofen significantly increased furosemide AUC(0-t) (37%) and AUC(0-inf) (36%) and decreased total body CL (27%), R(max) (19%) and CLR (23%) geometric mean ratios compared with furosemide control. Oral and topical diclofenac had no pharmacokinetic effects on furosemide. Ibuprofen increased sodium excretion (Ae(0-24), 16%) and decreased sodium R(max) (15%), and oral diclofenac decreased urine output (Vu(0-24), 15%). DETP had no effect on furosemide pharmacodynamics; total systemic exposure to diclofenac during DETP treatment was < 1% that of oral diclofenac. Treatments were generally safe, with 25 subjects reporting a total of 112 adverse events.
  
  
  CONCLUSIONS
  Pharmacodynamic effects were seen with oral diclofenac (urine output) and ibuprofen (urine sodium excretion). Furosemide also affected plasma and urine pharmacokinetic profiles. Pharmacologic effects of DETP on furosemide were not observed under these conditions. Additional research is warranted to delineate the potential interactions of other NSAIDs with furosemide and other loop diuretics.
authors.affiliation: Pfizer, Inc., Cary, NC, USA.
authors.forename: C A
authors.initials: CA
authors.lastname: Paterson
authors.forename: D
authors.initials: D
authors.lastname: Jacobs
authors.forename: S
authors.initials: S
authors.lastname: Rasmussen
authors.forename: S P
authors.initials: SP
authors.lastname: Youngberg
authors.forename: N
authors.initials: N
authors.lastname: McGuinness
mesh_terms: D000328:Adult; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000009:adverse effects / Q000493:pharmacokinetics / Q000494:pharmacology*; D019540:Area Under Curve; D018592:Cross-Over Studies; D004008:Diclofenac / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000493:pharmacokinetics / Q000494:pharmacology; D004232:Diuretics / Q000009:adverse effects / Q000493:pharmacokinetics / Q000494:pharmacology; D004347:Drug Interactions; D005260:Female; D005665:Furosemide / Q000009:adverse effects / Q000493:pharmacokinetics* / Q000494:pharmacology; D006801:Humans; D007052:Ibuprofen / Q000009:adverse effects / Q000493:pharmacokinetics / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D057968:Transdermal Patch; D055815:Young Adult
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D004232:Diuretics; C064142:diclofenac hydroxyethylpyrrolidine; D004008:Diclofenac; D005665:Furosemide; D007052:Ibuprofen