indinavir

CLINICAL USE


Protease inhibitor:Treatment of HIV infection, in combination with a nucleoside reverse transcriptase inhibitor

DOSE IN NORMAL RENAL FUNCTION

800 mg every 8 hours

PHARMACOKINETICS

  • Molecular weight &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp :711.9 (as sulphate)
  • %Protein binding &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp :60
  • %Excreted unchanged in urine &nbsp &nbsp : 10.4
  • Volume of distribution (L/kg) &nbsp &nbsp &nbsp :14
  • half-life – normal/ESRD (hrs)&nbsp &nbsp &nbsp :1.8/Unchanged

    DOSE IN RENAL IMPAIRMENT

    GFR (mL/MIN)

  • 20 to 50 &nbsp &nbsp : Dose as in normal renal function Monitor closely
  • 10 to 20 &nbsp &nbsp : Dose as in normal renal function Monitor closely
  • <10 &nbsp &nbsp &nbsp &nbsp &nbsp : Dose as in normal renal function Monitor closely

    DOSE IN PATIENTS UNDERGOING RENAL REPLACEMENT THERAPIES

  • CAPD &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp:Unlikely to be dialysed. Dose as in GFR <10 mL/min

  • HD &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp :Not dialysed. Dose as in GFR <10 mL/min
  • HDF/high flux &nbsp :Not dialysed. Dose as in GFR <10 mL/min
  • CAV/VVHD &nbsp &nbsp &nbsp:Unlikely to be dialysed. Dose as in GFR 10 to 20 mL/min

    IMPORTANT DRUG INTERACTIONS

    Potentially hazardous interactions with other drugs
  • Anti-arrhythmics: possibly increased amiodarone concentration – avoid concomitant use
  • Antibacterials: rifampicin increases metabolism – avoid concomitant use; increased rifabutin concentration and rifabutin reduces indinavir concentration – reduce dose of rifabutin by 50% and increase dose of indinavir; avoid with telithromycin in severe renal and hepatic failure
  • Antidepressants: plasma concentration reduced by St John’s wort – avoid concomitant use
  • Anti-epileptics: concentration possibly reduced by carbamazepine, phenytoin, primidone and barbiturates
  • Antifungals: ketoconazole inhibits metabolism – reduce dose of indinavir to 600 mg every 8 hours; concentration increased by itraconazole – consider reducing indinavir
  • Antimalarials: avoid concomitant use with artemether/lumefantrine
  • Antipsychotics: possibly increased risk of ventricular arrhythmias with pimozide and sertindole – avoid concomitant use; possibly inhibits aripiprazole metabolism – reduce aripiprazole dose
  • Antivirals: avoid with atazanavir; concentration reduced by efavirenz and nevirapine; with nelfinavir and darunavir, concentration of both drugs increased; concentration increased by ritonavir; saquinavir concentration increasedAnxiolytics and hypnotics: increased risk of prolonged sedation with alprazolam and midazolam – avoid concomitant useCilostazol: concentration of cilostazol possibly increased – avoid concomitant use
  • Ergot alkaloids: risk of ergotism – avoid concomitant useLipid-regulating drugs: increased risk of myopathy with simvastatin – avoid concomitant use; and possibly with atorvastatin5HT 1 agonists: concentration of eletriptan increased – avoid concomitant useSildenafil: concentration of sildenafil increased – reduce initial sildenafil dose
  • Vardenafil: concentration of vardenafil increased – avoid concomitant use

    ADMINISTRATION

    Reconstition

    Route

    Oral

    Rate of Administration

    Comments

    Drink 1.5 litres of water in 24 hours .380 indinAVirGive 1 hour before, or 2 hours after food, or with a low fat meal with water

    OTHER INFORMATION

    If giving with didanosine, leave 1 hour between each drugMild renal insufficiency is usually due to crystalluria, but a case of interstitial nephritis has been reportedIf nephrolithiasis with flank pain occurs (with or without haematuria), temporarily stop therapy (e.g. for 1–3 days)