Ketanserin is a potent antagonist of the serotonin (5-HT) receptor that is selective for 5-HT
2 (IC
50 = 6.3 nM; K
i = 2.1 nM).
1 It has no activity at 5-HT
1 receptors but does have activity at histamine type 1, α
1-adrenergic, and dopamine receptors with K
i values of 10, 10, and 220 nM, respectively. Ketanserin induces dose-dependent inhibition of contractile responses to 5-HT in isolated rat caudal artery, canine basilar, carotid, coronary and gastrosplenic arteries, and canine gastrosplenic and saphenous veins.
2 Ketanserin (10 mg/kg/day) significantly decreases blood pressure (BP), blood pressure variability (BPV), and hypertensive organ damage in spontaneously hypertensive rats.
3 Formulations containing ketanserin have been used to treat hypertension in early-onset preeclampsia.
4 
