Diazepam tolerance effects on vestibular function testing, Part I: Saccadic parameters during electronystagmography.
OBJECTIVE
Benzodiazepines, particularly diazepam (DZ), are used in clinical practice to suppress acute vestibular symptoms. There have been limited studies looking at the effects of tolerance to DZ on parameters designed to measure the integrity of the vestibular system and its interaction with the oculomotor and balance systems.


METHODS
In a double-blinded, repeated-measures design, we randomized 30 young healthy men into one of two treatment groups (diazepam and placebo) and assessed with electro-oculography the effects of clinical divided doses of DZ on saccadic eye movements and sedation over 16 days.


RESULTS
Only sedation and saccadic latency were significant (p < .05) for treatment group, indicating selective effects on different central nervous system mechanisms. No significant effect for time was seen in any of the variables measured. Bonferroni t-test comparisons of the DZ group among 3 days were significant (p < .017) between baseline and day 3 for saccadic latency and accuracy and between day 3 and day 16 for self-ratings of sedation.


CONCLUSIONS
Saccadic latency and accuracy and sedation ratings appear to be more sensitive to changes over time and less affected by subject variability than saccadic eye velocity. It remains questionable whether patients who have been on DZ for acute or extended periods of time need to discontinue the drug 48 hours before testing.
Blau
Patricia A
PA
Dept of Otorhinolaryngology, University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Blvd, Dallas, TX 75390-8876, USA.
Schwade
Nathan
N
Roland
Peter
P
D000328:Adult; D003975:Diazepam / Q000009:adverse effects* / Q000627:therapeutic use; D004311:Double-Blind Method; D004361:Drug Tolerance; D004584:Electronystagmography; D004585:Electrooculography; D018757:GABA Modulators / Q000009:adverse effects* / Q000627:therapeutic use; D006801:Humans; D006993:Hypnotics and Sedatives / Q000009:adverse effects; D008297:Male; D011930:Reaction Time / Q000187:drug effects; D012438:Saccades / Q000187:drug effects; D015837:Vestibular Diseases / Q000175:diagnosis / Q000188:drug therapy* / Q000503:physiopathology*; D014724:Vestibular Function Tests
D018757:GABA Modulators; D006993:Hypnotics and Sedatives; D003975:Diazepam