. Author manuscript; available in PMC: 2010 Aug 1.

Published in final edited form as: Parkinsonism Relat Disord. 2009 May 19;15(7):483–489. doi: 10.1016/j.parkreldis.2009.04.006

Table 2.

Oral Medications for Blepharospasm and Other Cranial Dystonias

Class	Names	Mechanism(s) of action	Most frequent side effects
Anticholinergic [84]	trihexyphenidyl benztropine	block acetylcholine receptors	dry mouth, constipation, blurred vision, mild memory impairment
Benzodiazepine [63]	clonazepam lorazepam diazepam	potentiate the effects of GABA on GABA_A receptors	drowsiness, disequilibrium
GABA_B receptor agonist [90]	baclofen	stimulates GABA_B receptors	drowsiness, disequilibrium, weakness
Dopamine precursor [91]	levodopa	converted to dopamine	nausea
Dopamine receptor agonist [92]	bromocriptine	stimulates D₂ dopamine receptors, 5-HT₂ antagonist	nausea, lightheadness, drowsiness
Neuroleptic [93]	pimozide haloperidol	blocks dopamine receptors (D₂ > D₃ > D₁ & D₄)	tardive dyskinesias^**
Monoamine depleter [93]	tetrabenazine	inhibits monoamine transporters in the brain	depression, drowsiness, Parkinsonism
Anticonvulsant [81]	levetiracetam	binds to the synaptic vesicle protein SV2A	irritability, headaches
Imidazopyridine [94]	zolpidem	binds to the benzodiazepine receptor 1	drowsiness, dizziness, headache
Atypical antipsychotic [95]	clozapine	blocks dopamine receptors (D₄ ≫D₁, D₂, D₃, & D₅), partial 5-HT_1A agonist, cholinergic and histaminergic antagonist	constipation, sedation, agranulocytosis
Serotonin receptor antagonist [96]	cyproheptadine	5-HT₂ antagonist, antihistaminic	drowsiness, nausea
Antiarrhythmic agent [97]	mexiletine	inhibits inward sodium currents	nausea, dizziness, tremor

None of these medications are FDA approved treatments for blepharospasm

^**

Tardive dyskinesias may be a permanent side effect