The effect of this inhalation mixture comes from a specific combination of volatile aromatic components that dissolve evenly in hot water due to the ethyl alcohol base. This ensures a consistent release of vapour.
- Racemic Menthol: This component creates the characteristic cooling feeling. It does not literally lower the temperature of the airways; instead, it interacts with cold-sensitive receptors. This interaction is what makes breathing feel fresher, lighter, and more open.
- Eucalyptus Tincture: This adds a sharp, resinous aroma rich in compounds naturally present in eucalyptus, especially eucalyptol. It complements the menthol to provide a pronounced fresh-air sensation.
When these substances evaporate with the steam, their scent reaches the nasal and oral passages. This liquid form allows for a stronger and more direct aromatic experience than simply placing dried herbs nearby, as the vapours are immediately recognisable and disperse effectively in warm water.