Ann Rehabil Med.  2016 Feb;40(1):177-181. 10.5535/arm.2016.40.1.177.

Zolpidem-Induced Arousal by Paradoxical GABAergic Stimulation: A Case Report With F-18 Flumazenil Positron Emission Tomography and Single Photon Emission Computed Tomography Study

• Kim C
• Kwon BS
• Nam KY
• Park JW
• Lee HJ

• KMID: 2155182
• DOI: http://doi.org/10.5535/arm.2016.40.1.177

Abstract

Zolpidem is a non-benzodiazepine drug that has selectivity for the gamma-aminobutyric acid (GABA) receptors. We experienced paradoxical effect of zolpidem in a 48-year-old male patient with hypoxic-ischemic brain injury after cardiac arrest. The patient was in stupor and could not communicate. His Glasgow Coma Scale (GCS) was E2M4V2 and Rancho Los Amigos (RLA) was grade III to IV. Zolpidem was prescribed to induce sedation but paradoxically, he became alert (GCS 15, RLA VII) and was able to communicate. The arousal lasted for 2 hours repeatedly following each administration of the medication. While he was alert, electroencephalogram showed the reversal of slow wave into beta range fast activity and F-18 flumazenil positron emission tomography (PET) showed increased GABAergic receptor activity in both frontoparietotemporal cortices. Single photon emission computed tomography (SPECT) also showed increased cerebral perfusion and reversal of cerebellar diaschisis.

Keyword

Hypoxia; Zolpidem; Arousal

MeSH Terms

Anoxia
Arousal*
Brain Injuries
Electroencephalography
Electrons*
Flumazenil*
gamma-Aminobutyric Acid
Glasgow Coma Scale
Heart Arrest
Humans
Male
Middle Aged
Perfusion
Positron-Emission Tomography*
Stupor
Tomography, Emission-Computed, Single-Photon*
Flumazenil
gamma-Aminobutyric Acid

Figure

• 

  Fig. 1 The electroencephalography show slow wave before medication (zolpidem-off, A) and the reversal of slow wave to beta range fast activity after medication (zolpidem-on, B).

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  Fig. 2 F-18 flumazenil positron emission tomography ([18F]-FMZ-PET) show increased GABAergic receptor activity in bilateral frontoparietotemporal cortex at zolpidem-on (B), as compared to zolipdem-off (A).

• 

  Fig. 3 Single photon emission computed tomography (SPECT) show increased perfusion of left parietal lobe after administration of zolpidem (A) and improvement of diaschisis in cerebellum (B).

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