Hallucinations

My father-in-law has Parkinson's and is also on dialysis.  Recently, he was prescribed Amantadine 200 mg per day.  He began to have hallucinations.  His neurologist said this was due to the Parkinson's and it was just a coincidence that it started when he went on Amantadine.  He said the Amantadine is metabolized in the liver, so his being on dialysis has no bearing on the dosage.  Is this correct?  What should we do?

[CCF-Neuro-M.D.-JT]

Amantadine is actually excreted unmetabolized in the urine. Patients with kidney disease need to have the ok by their kidney doctors before starting on the medication as it can accumulate in the body with impaired kidney function, especially if they require dialysis. There is one study from the Annals of Medicine in 1980 that looked at dialysis patients and levels of amantadine before and after dialysis. THey found that only a small fraction of the drug was removed with each dialysis treatment.

And yes, it can cause hallucinations, especially when it's withdrawn too quickly or if there's too much in the body. On the other hand, dopamine and dopamine like drugs can also cause hallucinations. This can be treated with decreasing the med or adding an antipsychotic medication such as Seroquel or Olanzapine. In your father in law's case, talk to his renal doc to make sure that amantadine is ok. Then discuss your concerns with his neuro. Good luck.

[MrsSB]

A related discussion, weening off Amantadine was started.