Brompheniramine ((±)-Brompheniramine) is a potent and orally active alkylamine class antihistamine. Brompheniramine is a selective antagonist of histamine H1 receptor (Kd = 6.06 nM). Brompheniramine can be used in the research of allergic rhinitis that has anticholinergic, antidepressant and anesthetic properties. Brompheniramine can block the calcium channels, sodium channels, and hERG channels with IC 50 s of 16.12 μM, 21.26 μM, and 0.90 μM, respectively [1] [2] [3] [4].

Brompheniramine (0.1-100 μM) blocks hERG K + channels expressed in CHO cells in a concentration-dependent manner with an IC 50 of 0.90±0.14 μM, and reduced peak tail current amplitude measured at -60 mV (cells are depolarized for 2 s to +20 mV from a holding potential of -80 mV followed by a 3s repolarization back to -60 mV) [3]. Brompheniramine (1, 10 and 100 μM) significantly shortens the APD 50 and depresses the plateau phase on the action potential in guinea pig papillary muscle, as well as slightly prolongs the APD 90 in guinea pig papillary muscle at 10 and 100 μM [3]. Brompheniramine (0.1-100 μM) inhibit the amplitude of the Ca 2+ channel currents in rat ventricular myocytes by 14.1±1.1, 31.1±5.8, 38.0±3.8 and 90.2±3.7% at 0.1, 1, 10 and 100 μM, respectively [3]. Brompheniramine blocks muscarinic cholinergic receptors in human chinese hamster ovary (CHO) cells [4].

Brompheniramine (0.3-3 μM; SC, single dosage) induces cutaneous analgesia in rats [1]. Animal Model: Male Sprague-Dawley rats [1] Dosage: 0.3, 0.6, 1.1, 1.5 and 3.0 μM Administration: SC, single dosage Result: Provoked cutaneous analgesia in a dose-dependent manner, with an EC 50 value of 0.66 μM, and induced prolonged analgesic duration.