Lerimazoline is a sympathomimetic drug that belongs to the imidazoline class of compounds, and is used as a nasal decongestant. Lerimazoline displayed high affinity for the 5-HT1A receptor and for the 5-HT1D receptor. Binding affinity estimates for α1-adrenoceptor, 5-HT2A, and D2 receptors were more than ten times lower. The mechanism of vasoconstrictor action of lerimazoline encompasses both, the activation of 5-HT2A, and to a lesser degree α1 -adrenergic receptors. These results also suggest that lerimazoline is an “atypical” decongestant. It inhibits secretion of nasal mucus. Lerimazoline causes hypertension.