e200921c_sity_of_Michigan_Health_System__Why
[Supplement] 1 Star Eucalyptus Oil Eucalyptus oil [Why] 
Eucalyptus oil is often used in a steam inhalation to help clear nasal and sinus congestion. Eucalyptus oil is often used in a steam inhalation to help clear nasal and sinus congestion. It is said to work similarly to menthol, by acting on receptors in the nasal mucous membranes, leading to a reduction of nasal stuffiness.58 Peppermint may have a similar action and is a source of small amounts of menthol.
Common Cold/Sore Throat (Holistic) | University of Michigan Health System
Why