Answer
The kidneys remove most amantadine unchanged. Reduced kidney function can cause accumulation and serious neurological toxicity, and severe renal disease is contraindicated.
Sources for this answer
- Amantadine hydrochloride 50 mg/5 ml Oral Solution — Current selected SmPCemc · Summary of Product Characteristics
- Amantadine hydrochloride 100mg capsules — Current selected SmPCemc · Summary of Product Characteristics