CLINICAL USE


Hypertension

DOSE IN NORMAL RENAL FUNCTION

250 mg 2–3 times a day, increasing to a maximum dose of 3 g daily

PHARMACOKINETICS

  • Molecular weight &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp :238.2
  • %Protein binding &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp :<15
  • %Excreted unchanged in urine &nbsp &nbsp : 25–40
  • Volume of distribution (L/kg) &nbsp &nbsp &nbsp :0.5
  • half-life – normal/ESRD (hrs)&nbsp &nbsp &nbsp :1.6–2/6–16

    DOSE IN RENAL IMPAIRMENT

    GFR (mL/MIN)

  • 20 to 50 &nbsp &nbsp : Dose as in normal renal function and adjust according to response
  • 10 to 20 &nbsp &nbsp : Dose as in normal renal function and adjust according to response
  • <10 &nbsp &nbsp &nbsp &nbsp &nbsp : Dose as in normal renal function and adjust according to response

    DOSE IN PATIENTS UNDERGOING RENAL REPLACEMENT THERAPIES

  • CAPD &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp:Dialysed. Dose as in GFR
  • <10 &nbsp &nbsp &nbsp &nbsp &nbsp : mL/min

  • HD &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp :Dialysed. Dose as in GFR
  • <10 &nbsp &nbsp &nbsp &nbsp &nbsp : mL/min
  • HDF/high flux &nbsp :Dialysed. Dose as in GFR
  • <10 &nbsp &nbsp &nbsp &nbsp &nbsp : mL/min
  • CAV/VVHD &nbsp &nbsp &nbsp:Probably dialysed. Dose as in GFR 10 to 20 mL/min

    IMPORTANT DRUG INTERACTIONS

    Potentially hazardous interactions with other drugs
  • Anaesthetics: enhanced hypotensive effect
  • Antidepressants: avoid concomitant use with MAOIs
  • Lithium: neurotoxicity (without increased plasma-lithium concentrations)Salbutamol: acute hypotension reported with salbutamol infusions

    ADMINISTRATION

    Reconstition

    Route

    Oral

    Rate of Administration

    Comments

    OTHER INFORMATION

    Active metabolites with long half-life Interferes with serum creatinine measurementOrthostatic hypotension more common in renally impaired patients.