Answer
Benzalkonium chloride in the Thornton & Ross Ltd eucalyptus oil + menthol inhalation product may cause wheezing and breathing difficulties (bronchospasm), especially in people with asthma.
Sources for this answer
- Menthol and Eucalyptus Inhalation BP 1980Thornton & Ross Ltd · emc · SmPC §4.4 Special warnings and precautions for use · Version 4Document updated
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