According to a research study published in Scientific Reports, chloroquine and quinine prevented airway inflammation and other characteristics of allergic asthma in mice, MedicalNewsToday reports. The compounds, which are used to treat malaria, prevented the development of allergic asthma in mice “by activating the rodents’ bitter taste receptors,” MNT reports.

The two compounds are also added to tonic water in order to give the beverage its distinctive, bitter taste.

According to scientists, previous research found that activating bitter taste receptors on the tongue, called TAS2Rs, led to the relaxation of smooth muscle in the airways of asthma mouse models.

Researchers gave mouse models of allergic asthma intranasal doses of either chloroquine or quinine. Not only did chloroquine and quinine prevent airway inflammation in the mice, but the bitter compounds also prevented other key characteristics of allergic asthma, including mucus accumulation and structural changes to the airway.