Amantadine Side Effects?

  Last week I was admitted to the hospital
  on an emergency basis, due to elevated temp.
  and extreme tenderness in the upper abdomen.
  These turned out to be symptoms of some kind
  of gall bladder and liver inflammation--but
  an entire team of physicians could not determine
  any cause. Tests were negative for gallstones, Hep
  A, B & C, mononucleosis and numerous other possible
  culprits.
  The physicians' last best guess was that the
  inflammation was due to a drug interaction or
  allergic response to one of the 3 drugs I was
  taking just prior to admission: Interferon-Beta 1a
  (Avonex); Baclofen; and Amantadine.
  I was released from the hospital with my liver
  enzymes improving, though not as rapidly as the
  doctors' had expected. I was on Augmentin only.
  Under my neurologist's care I am to begin adding
  my usual doses of my existing prescriptions,
  one drug at a time, until the cause of my
  difficulties is uncovered.
  I was feeling better each day, saw my neurologist,
  and restarted the Amantadine and fever symptoms
  came back, along with slight abdominal tenderness.
  I can find no record of any such reactions to Amantadine.
  Every neurologist and doctor I have spoken to seems
  surprised at such a reaction.
  Has anybody heard of any liver or gall bladder side
  effect to Amantadine? Or does anybody have any insight
  into what could be causing these symptoms?
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Sorry about the late reply.
I have used amantadine for many patients with Parkinson's disease and thus have some experience with it. I have never encountered a drug hepatitis with it. Most commonly, we see cognitive or other problems related to anticholinergic side effects. Also, some people get swelling of legs or a blotchy redness called livedo reticularis which I've seen before.
Interestingly, the 1998 PDR states (page 919) "Rare instances of reversible elevation of liver enzymes have been reported in patients receiving Symmetrel(TM), though a specific relationship between the drug and such changes has not been established."
I don't know if this helps - elevation of liver enzymes can be asymptomatic, and many drugs do that with no distress to the patient. Drug-induced hepatitis is another matter. It's not listed even in the "rare (less than 0.1%)" category of adverse reactions on page 920.
Good luck. CCF MD mdf.