Medicine & USMLE

Benztropine, Trihexyphenidyl

Other Neuro Pharm
  1. Ramelteon
  2. Triptans
  3. Benzodiazepines - Function
  4. Zolpidem Zaleplon Eszopiclone
  5. Suvorexant
  6. Bromocriptine (Ergot Dopamine Agonists)
  7. Pramipexole, Ropinirole
  8. Amantadine
  9. Levodopa, Carbidopa
  10. Entacapone, Tolcapone
  11. Selegiline and Rasagiline
  12. Benztropine, Trihexyphenidyl
  13. Tetrabenazine
  14. Baclofen
  15. Memantine
  16. Riluzole
  17. Full Opioid Agonists
  18. Partial Opioid Agonists
  19. Dextromethorphan
  20. Tramadol
  21. Naloxone
  22. Naltrexone


Benztropine and Trihexyphenidyl are drugs used to treat Parkinson's disease and drug-induced Parkinsonism. They work by functioning as anticholinergic medications. Specifically, anticholinergic drugs help improve tremor and rigidity seen in Parkison’s disease and drug-induced parkinsonism. Given their mechanism, it should also make sense that benztropine and trihexyphenidyl can cause anticholinergic symptoms.

Key Points

  • Benztropine, Trihexyphenidyl
    • Mechanism
      • Act as Anticholinergic
    • Clinical Use
      • Treat tremor in Parkinson’s disease
        • Improve tremor and rigidity but have little effect on bradykinesia in Parkinson disease
        • Under normal conditions, dopamine and acetylcholine are in electrochemical balance in the basal ganglia
          • Decreased dopamine in Parkinson's disease (PD) leads to increased cholinergic sensitivity.
      • Drug-induced parkinsonism (1st line)
    • Adverse Effects:
      • Anticholinergic side effects