Amantadine is a drug used to treat Parkinson's disease. It works by increasing the availability of dopamine in the brain. Amantadine can also be used to treat the flu by impairing the uncoating of the influenza virus. Side effects of amantadine use include anticholinergic symptoms, as well as non-specific findings like edema, livedo reticularis, and ataxia.

Key Points

  • Amantadine
    • Mechanism
      • Increases dopamine availability
        • Increases dopamine release from presynaptic neurons        
        • Decreases dopamine reuptake into presynaptic neurons
    • Clinical use
      • Treats Parkinson disease
      • Antiviral against influenza virus A
        • Impairs uncoating or disassembly of the influenza A virion after host cell endocytosis
        • Limited use due to widespread viral resistance
    • Adverse effects
      • Anticholinergic (dry mouth, nausea, hallucinations, AMS, blurry vision)
        • Avoid in elderly
      • Peripheral edema
      • Ataxia
      • Livedo reticularis
        • Mottled reticulated vascular pattern that appears as a lace-like purplish discoloration of the skin.