From the Guidelines
Amantadine should be considered as an adjunctive treatment in post-stroke rehabilitation to potentially enhance recovery of motor function and reduce fatigue, though it is not considered first-line therapy. The typical dosage ranges from 100-400 mg daily, often starting at 100 mg once or twice daily and gradually increasing as tolerated 1. Treatment duration varies based on individual response, but is commonly continued for several weeks to months while monitoring for benefits. Amantadine works primarily by enhancing dopaminergic neurotransmission and has NMDA receptor antagonist properties, which may help modulate neuroplasticity during recovery. Patients should be aware of common side effects including insomnia, dizziness, hallucinations, and livedo reticularis (a skin condition). Amantadine should be used cautiously in patients with renal impairment, seizure disorders, or heart failure, and dosage adjustments are necessary for those with kidney dysfunction.
Key Considerations
- The evidence for using Amantadine in post-stroke rehabilitation is limited and inconsistent, making it essential to have realistic expectations about its effects 1.
- Stroke rehabilitation involves programs to reduce impairment, enhance recovery, and adapt to the persisting disability, and Amantadine may play a role in this process.
- Patients who have had an ischemic or hemorrhagic stroke with resultant impairments and limitations in activities should be referred to rehabilitation services for an assessment of rehabilitation needs 1.
- The organization and delivery of stroke care can vary, and Amantadine may be used as part of a multidisciplinary approach to rehabilitation 1.
Potential Benefits and Risks
- Potential benefits of Amantadine in post-stroke rehabilitation include improving attention, reducing fatigue, and enhancing motor recovery.
- Common side effects of Amantadine include insomnia, dizziness, hallucinations, and livedo reticularis (a skin condition).
- Amantadine should be used cautiously in patients with renal impairment, seizure disorders, or heart failure, and dosage adjustments are necessary for those with kidney dysfunction.
From the Research
Role of Amantadine in Post-Stroke Rehabilitation
Amantadine is a neurostimulant that may improve cognitive and functional recovery post-stroke, but the existing study results vary, and no comprehensive review has been published until recently 2. The use of amantadine in clinical practice is still limited, despite its increasing evidence in the emergence of vegetative state after traumatic brain injury 3.
Administration Practices and Effectiveness
Amantadine administration practices post-stroke include initiation 39 days post-stroke, with most common initial doses of 100 mg once or twice daily, and a final daily dose of 200 mg/day 2. The most common indication is consciousness disorders 2. A positive response in at least one clinical effectiveness measure was reported in 70% of amantadine publications 2.
Safety and Adverse Effects
Potential adverse drug effects were reported in approximately 50% of publications, most commonly visual hallucinations with amantadine (2% of patients) and dizziness (5% of patients) and dry eyes or mouth (5% of patients) 2. Sleep disruption was also reported as a common potential adverse drug effect (16%) 4.
Comparison with Other Neurostimulants
Amantadine and modafinil may improve cognitive and functional recovery post-stroke, but higher-quality data are needed to confirm this conclusion, especially in the acute care setting 2, 4. Memantine is also commonly used in the acute rehabilitation setting following brain injuries, despite its lack of FDA-approval for neuro-recovery 5.
Clinical Applications and Future Directions
Amantadine may be used as a trigger of the rehabilitation program, with significant clinical and functional improvements, and emergence from vegetative state to minimally conscious state 3. Future controlled studies with a neurostimulant administration protocol, prospective evaluation, and discretely defined response and safety criteria are needed to confirm these encouraging findings 4. Currently, most convincing evidence exists for amantadine for acceleration of functional recovery after severe traumatic brain injury 6.
- Key findings:
- Amantadine may improve cognitive and functional recovery post-stroke
- Administration practices vary, but common initial doses are 100 mg once or twice daily
- Potential adverse effects include visual hallucinations, dizziness, and sleep disruption
- Higher-quality data are needed to confirm the effectiveness of amantadine in acute care settings
- Amantadine may be used as a trigger of the rehabilitation program, with significant clinical and functional improvements