title: Assessment of the drug-drug interactions between fimasartan and hydrochlorothiazide in healthy volunteers.
abstract: OBJECTIVE
  Fimasartan is a selective angiotensin II receptor blocker. Hydrochlorothiazide (HCTZ), which is used to treat hypertension and edematous conditions, is coadministered with many antihypertensive agents.
  
  
  METHODS
  An open-label, randomized, multiple-dosing, 2-arm, 1-sequence, 2-period study was conducted to assess the effects of fimasartan (240 mg) on HCTZ (25 mg) or vice versa in 18 and 14 healthy male volunteers, respectively. During each drug administration period, drugs were given once daily for 7 days, with a 7-day washout period between the 2 administration periods.
  
  
  RESULTS
  The respective geometric mean ratios of fimasartan for AUC τ,ss and C max,ss with HCTZ were 1.30 [90% confidence interval (CI), 0.84-2.01] and 1.17 (90% CI, 0.93-1.47) compared with fimasartan alone. The respective geometric mean ratios of HCTZ for AUC τ,ss and C max,ss with fimasartan were 0.94 (90% CI, 0.84-1.04) and 0.88 (90% CI, 0.80-0.97) compared with HCTZ alone. Plasma renin activity indicated no significant differences between fimasartan monotherapy and coadministered treatment.
  
  
  CONCLUSIONS
  Fimasartan administered alone or in combination with HCTZ was well tolerated at the described dosages. Coadministration of fimasartan increased the urinary excretion of HCTZ and urine volume, but these observations are unlikely to have any clinical relevance.
authors.affiliation: Department of Pharmacology and Clinical Pharmacology, Seoul National University College of Medicine and Hospital, Seoul, Korea.
authors.forename: Hyewon
authors.initials: H
authors.lastname: Jeon
authors.forename: Kyoung Soo
authors.initials: KS
authors.lastname: Lim
authors.forename: Kwang-Hee
authors.initials: KH
authors.lastname: Shin
authors.forename: JaeWoo
authors.initials: J
authors.lastname: Kim
authors.forename: Seo Hyun
authors.initials: SH
authors.lastname: Yoon
authors.forename: Joo-Youn
authors.initials: JY
authors.lastname: Cho
authors.forename: Sang-Goo
authors.initials: SG
authors.lastname: Shin
authors.forename: In-Jin
authors.initials: IJ
authors.lastname: Jang
authors.forename: Kyung-Sang
authors.initials: KS
authors.lastname: Yu
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000450:Aldosterone / Q000097:blood; D000959:Antihypertensive Agents / Q000097:blood / Q000493:pharmacokinetics* / Q000494:pharmacology* / Q000652:urine; D001713:Biphenyl Compounds / Q000097:blood / Q000493:pharmacokinetics* / Q000494:pharmacology* / Q000652:urine; D002851:Chromatography, High Pressure Liquid; D004347:Drug Interactions; D004359:Drug Therapy, Combination; D006801:Humans; D006852:Hydrochlorothiazide / Q000097:blood / Q000493:pharmacokinetics* / Q000494:pharmacology* / Q000652:urine; D008297:Male; D008875:Middle Aged; D011743:Pyrimidines / Q000097:blood / Q000493:pharmacokinetics* / Q000494:pharmacology* / Q000652:urine; D012083:Renin / Q000097:blood; D053719:Tandem Mass Spectrometry; D013777:Tetrazoles / Q000097:blood / Q000493:pharmacokinetics* / Q000494:pharmacology* / Q000652:urine; D055815:Young Adult
chemical_list: D000959:Antihypertensive Agents; D001713:Biphenyl Compounds; D011743:Pyrimidines; D013777:Tetrazoles; D006852:Hydrochlorothiazide; D000450:Aldosterone; D012083:Renin; C558933:fimasartan