amantadine
Adjunctive therapy • Brands: Symmetrel, Gocovri, Osmolex ER
Last reviewed: 2025-12-30
General information
- Class: Adjunctive therapy
- Common US brands: Symmetrel, Gocovri, Osmolex ER
- Therapeutic drug monitoring not routinely recommended.
- Last reviewed: 2025-12-30
Dosing & forms
- Forms/strengths: —
- Frequency: —
- Food: —
- Typical range: —
Mechanism (brief)
Dopaminergic/NMDA-modulating antiparkinson agent (also historically used as an antiviral) that can treat drug-induced extrapyramidal reactions, including antipsychotic-induced parkinsonism. Not an anticholinergic; may be considered when anticholinergic cognitive burden is a concern, balancing potential benefit against neuropsychiatric adverse effects and renal-dose constraints.
Metabolism & Half‑life
- Metabolism: Not extensively metabolized; an N-acetylated metabolite has been identified (label).
- Half‑life: Single-dose mean 17 h; Single-dose range 10–25 h
Therapeutic Drug Monitoring (TDM)
Recommended: No
Monitoring highlights
- —
Sources
- Amantadine hydrochloride capsules prescribing information — DailyMed (2024)
- A Double-Blind Study of Amantadine Hydrochloride versus Benztropine Mesylate in Drug-Induced Parkinsonism — European Neurology (1974)
- Amantadine versus trihexyphenidyl in the treatment of neuroleptic-induced parkinsonism — American Journal of Psychiatry (1976)
- Recognition and Management of Antipsychotic-Induced Parkinsonism in Older Adults A Narrative Review — Medicines (2021)
- AGNP Consensus Guidelines for Therapeutic Drug Monitoring in Neuropsychopharmacology — Pharmacopsychiatry (2018)