HEALTHY LIFESTYLE




Amantadine hydrochloride
Amantadine hydrochloride.JPG

Amantadine hydrochloride

CLINICAL USE

  • Parkinson’s disease (but not drug induced extrapyramidal symptoms)
  • Post-herpetic neuralgia
  • Prophylaxis and treatment of influenza A

    DOSE IN NORMAL RENAL FUNCTION

  • Parkinson’s disease: 100 mg once a day, increased after one week to 100–200 mg twice a day
  • Post-herpetic neuralgia: 100 mg twice a day for 14 days
  • Influenza A: treatment – 100 mg once a day for 4–5 days; prophylaxis – 100 mg once a day

    PHARMACOKINETICS

  • Molecular weight                           : 187.7
  • %Protein binding                           : 67
  • %Excreted unchanged in urine     : 90
  • Volume of distribution (L/kg)       : 5–10
  • half-life – normal/ESRD (hrs)      : 15/500

    DOSE IN RENAL IMPAIRMENT

    GFR (mL/MIN)

    35–50 100 mg every 24 hours 15–35 100 mg every 48–72 hours <15 100 mg every 7 days

    DOSE IN PATIENTS UNDERGOING RENAL REPLACEMENT THERAPIES

  • CAPD                : Not dialysed. Dose as in GFR <10 mL/min
  • HD                     : Not dialysed. Dose as in GFR <10 mL/min
  • HDF/high flux   : Unknown dialysability. Dose as in GFR<15 mL/min
  • CAV/VVHD      : Unknown dialysability. Dose as in GFR=15–35 mL/min

    IMPORTANT DRUG INTERACTIONS

    Potentially hazardous interactions with other drugs
  • Memantine: increased risk of CNS toxicity – avoid concomitant use; effects of amantadine possibly enhanced

    ADMINISTRATION

    Reconstition

    Route

    Oral

    Rate of Administration

    Comments

    OTHER INFORMATION

  • Peripheral oedema may occur in some patients; should be considered when the drug is prescribed for those with congestive heart failure
  • Side effects are often mild and transient; usually appear within 2–4 days of treatment and disappear 24–48 hours after discontinuation of the drug
  • Due to extensive tissue binding, <5% of a dose is removed by a 4 hour haemodialysis session
  • A reduction in creatinine clearance to 40 mL/min may result in a 5-fold increase in elimination half-life
  • other drugs