Glycerol Test

Glycerol is a potent osmolar agent which dehydrates the inner ear improving cochlear function and hearing.

Indications –

  • Fluctuating Sensorineural Hearing Loss
  • Episodic Vertigo
  • Ear Fullness / heaviness
  • Tinnitus

Method –

Baseline Audiometry is taken just before glycerol solution intake.

Oral Dose ingestion of 1.2ml/Kg or 1.5g/Kg body weight with addition of physiologic saline. Glycerol solution intake reduces fluid abnormalities in the inner ear.

Hearing thresholds improve temporarily (for a few hours) which is measured by periodic audiograms. Most patients suffer headache and nausea after drinking glycerol solution which usually subsides after few hours.

Results –

1. Glycerol Test Positive –
Suggests Meniere’s Disease indicating that Endolymphatic Hydrops contributes to hearing loss, vertigo and tinnitus. In clinical practice indicates reversibility and treatment with diuretic drugs may be helpful.

2. Glycerol Test Negative –
Suggests other types of cochlear deafness. Also seen in Normals.