Onitin is a natural product, that can be isolated from Onychium siliculosum. Onitin is also a non-competitive antagonist of histamine. Onitin shows activity in blocking the peristaltic reflex of the guinea-pig ileum, in inhibition of the responses of guinea-pig ileum to histamine and of inhibition of the responses of guinea-pig tracheal muscle to histamine[1].
4-Methylhistamine is a potent agonist of histamine 4 receptor (H4R). 4-Methylhistamine has the potential for the research of immune-related diseases such as cancer and autoimmune disorders[1][2].
Mequitazine is a potent, nonsedative and long-acting histamine H1 antagonist.
Acreozast (TYB-2285) is a histamine release inhibitor. Acreozast inhibits the histamine release primed with IL-3. Acreozast might regulate allergic inflammation in vivo by the suppression of mediator release primed with IL-3[1].
Diphenhydramine HCl (Benadryl), a histamine H1 antagonist used as an antiemetic, antitussive, for dermatoses and pruritus, for hypersensitivity reactions, as a hypnotic, an antiparkinson, and as an ingredient in common cold preparations.Target: Histamine H1 receptorDiphenhydramine HCl (Benadryl), a histamine H1 antagonist used as an antiemetic, antitussive, for dermatoses and pruritus, for hypersensitivity reactions, as a hypnotic, an antiparkinson, and as an ingredient in common cold preparations. It has some undesired antimuscarinic and sedative effects. Diphenhydramine competes with free histamine for binding at HA-receptor sites. This antagonizes the effects of histamine on HA-receptors, leading to a reduction of the negative symptoms brought on by histamine HA-receptor binding.
Samelisant (SUVN-G3031) is a potent and selective histamine H3 receptor (H3R) inverse agonist with good brain penetration and oral bioavailability. Samelisant has a similar binding affinity towards human (hH3R; Ki=8.7 nM) and rat (rH3R;Ki=9.8 nM) H3R indicating no inter-species differences. Samelisant can be used for the research of sleep-related disorders[1].
Tesmilifene fumarate (DPPE fumarate), an H1C receptor antagonist, potentiates a wide range of cytotoxics and even to offer some protection of normal cells[1][2].
Dothiepin (Dosulepin; Dothep) is an antidepressant agent with sedative/anxiolytic activity. Dothiepin is an inhibitor preferring of noradrenaline uptake than serotonin uptake. Dothiepin facilitates noradrenergic neurotransmission via inhibiting the neuronal uptake. Dothiepin is also an antagonist of histamine H1-receptor without cardiotoxicity. Dothiepin exhibits significant analgesic activity in psychogenic facial pain，idiopathic fibromyalgia syndrome or rheumatoid arthritis[1].
Oxomemazine is a phenothiazine-based histamine H1-receptor blocker with pronounced antimuscarinic properties. Oxomemazine is a selective antagonist for muscarinic M1 receptor, displays about 20-fold difference in the affinity for high (Ki = 84 nM, M1 receptor) and low (Ki = 1.65 μM, M2 receptor) affinity sites[1]. Oxomemazine an antihistamine and anticholinergic agent used for the study of cough treatment[2].
Chlorphenoxamine is an antihistamine and anticholinergic used as an antipruritic and antiparkinsonian agent. Target: Histamine Receptor
Antihistamine-1 is a H1-antihistamine (Ki=6.9 nM) with acceptable blood-brain barrier penetration and also an inhibitor of CYP2D6 and hERG channel with IC50s of 5.4 and 0.8 μM, respectively.
Thiethylperazine dimaleate is a phenothiazine derivate, and an orally active dopamine D2-receptor and histamine H1-receptor antagonist. Thiethylperazine dimaleate is also a slective ABCC1activator that reduces amyloid-β (Aβ) load in mice. Thiethylperazine dimaleate has anti-emetic, antipsychotic and antimicrobial effects[1][2][3].
INCB38579 is an orally active, highly brain penetrable, and selective histamine H4 receptor (HH4R) antagonist (hH4R IC50=4.8 nM, mH4R IC50=42 nM, rH4R IC50=32 nM). INCB38579 shows anti-inflammatory pain and anti-pruritic activities[1].
A-943931 is a potent and selective histamine H4 receptor (H4R) antagonist with pKi values of 4.6, 3.8 nM for human and rat H4R, respectively. A-943931 shows anti-inflammatory and antinociceptive efficacy[1][2].
VUF 5681 dihydrobromide is a neutral antagonist of histamine H3 receptor. VUF 5681 dihydrobromide also has partial agonist function of H3 receptor. VUF 5681 dihydrobromide blocks the effects of Thioperamide (HY-12206). VUF 5681 dihydrobromide is used in central nervous system disease research[1][2].
A 331440 hydrochloride is a histamine H3 receptor antagonist. A 331440 hydrochloride binds potently and selectively to human and rat histamine H3 receptors (Ki≤25 nM). A 331440 hydrochloride can be used for antiobesity research[1].
Loratadine n-oxide is a metabolite of Loratadine. Loratadine n-oxide shows antihistamine activity[1].
Bavisant Hcl hydrate(JNJ-31001074) is a highly selective, orally active antagonist of the human H3 receptor with a novel mechanism of action, involving wakefulness and cognition, with potential as a treatment for ADHD. IC50 Value: Target: H3 receptorin vitro: Bavisant completed a phase II ADHD trial, but no results have been reported [1].in vivo: Mean change from baseline in the total ADHD-RS-IV score at day 42 (primary efficacy endpoint) was -8.8 in the placebo group versus -9.3, -11.2 and -12.2 in the bavisant 1?mg/day, 3?mg/day and 10?mg/day groups, respectively; the change in the 10?mg/day group was not statistically superior to placebo (p=0.161), and hence statistical comparisons of the 1?mg/day and 3?mg/day groups with placebo based on a step-down closed testing procedure were not performed [2].Clinical trial: A Study to Characterize the Pharmacokinetics and Effect of Food on JNJ-31001074 in Healthy Volunteers. Phase 2
Doxylamine, a first generation antihistamine, is a histamine (H1) receptor antagonist. Doxylamine is also a local analgesic agent and effective hypnotic agent[1][2][3].
AVN-101 hydrochloride is a potent, brain-penetrant and orally active 5-HT7 receptor antagonist (Ki of 153 pM), with slightly lesser potency toward 5-HT6, 5-HT2A, and 5HT-2C receptors (Ki values of 2.04 nM, 1.56 nM, and 1.17 nM, respectively). AVN-101 hydrochloride also exhibits a rather high affinity toward histamine H1 (Ki of 0.58 nM) and adrenergic α2A, α2B, and α2C (Ki= 0.41-3.6 nM) receptors. AVN-101 hydrochloride can be studied in such diseases as general anxiety disorders, depression, schizophrenia, and multiple sclerosis[1].
Buclizine dihydrochloride is an orally active antihistamine antiallergic compound. Buclizine dihydrochloride is a potent teratogen in the rat[1][2][3].
(R)-(+)-Dimethindene maleate is an orally active H1-receptor blocker with antihistaminic properties in pigs[1].
A-940894 is a potent histamine H4 receptor antagonist, with Ki values of 7.6 nM (rat H4) and 71 nM (human H4). A-940894 exhibits with anti-inflammatory properties[1].
Tripelennamine Hcl, a H1-receptor antagonist, is a psychoactive drug and member of the pyridine andethylenediamine classes that is used as an antipruritic and first-generation antihistamine.IC50 Value:Target: Histamine H1 receptorTripelennamine can be used in the treatment of asthma, hay fever, rhinitus and urticaria.in vitro: Arterial and mixed venous blood-gas and pH measurements were made at rest before and after saline or drug administration and during incremental exercise leading to maximal exertion at 14 m/s on 3.5% uphill grade for 120 s. Galloping at this workload elicited maximal heart rate and induced exercise-induced pulmonary hemorrhage in all horses in both treatments, thereby indicating that capillary stress failure-related pulmonary injury had occurred [1].in vivo: The data obtained (median and range in brackets) in camels and horses, respectively, were as follows: the terminal elimination half-lives were 2.39 (1.91-6.54) and 2.08 (1.31-5.65) h, total body clearances were 0.97 (0.82-1.42) and 0.84 (0.64-1.17)L/h/kg. The volumes of distribution at steady state were 2.87 (1.59-6.67) and 1.69 (1.18-3.50) L/kg, the volumes of the central compartment of the two compartment pharmacokinetic model were 1.75 (0.68-2.27) and 1.06 (0.91-2.20) L/kg [2]. After intramuscular administration of 50 or 100 mg tripelennamine, mean plasma concentrations at 30 minutes were 105 and 194 ng/ml, respectively, and mean plasma t1/2 values were 2.9 and 4.4 hours, respectively [3].
Lavoltidine (Loxtidine) is an an orally active, irreversible and highly potent histamine H2-receptor antagonist. Lavoltidine strongly inhibits gastric acid secretion and also induces hypergastrinemia[1].
Alcaftadine-D3 (R89674-D3) is a deuterium labeled Alcaftadine. Alcaftadine (HY-17039) is a H1 histamine receptor antagonist[1].
Dimethothiazine (Dimetotiazine; Fonazine) is an orally active tricyclic anti-histamine, anti-5-HT agent with a high activity against decerebrate rigidity, a little sedative activity and little soporific action. Dimethothiazine can reduce or abolish the effects of both static and dynamic fusimotor activity on the muscle spindle in decerebrate cat. Dimethothiazine can be used to research hemicrania and spasticity[1][2][3].
Carbinoxamine maleate salt is a histamine H1 receptor antagonist.
Pitolisant hydrochloride is a potent and selective nonimidazole inverse agonist at the recombinant human histamine H3 receptor (Ki=0.16 nM).
Desloratadine(Sch34117) is a potent antagonist for human histamine H1 receptor used to treat allergies.Target: Histamine H1 ReceptorDesloratadine binds to the human H1 receptor with Ki value of 0.87 nM in displacing tritiated mepyramine. Desloratadine (100 nM to 10 μM) inhibits both IgE-mediated and non-IgE-mediated generation of the cytokines IL-4 and IL-13 by human basophils. Desloratadine (300 nM to 100 μM) inhibits both IgE and non-IgE-mediated histamine release from human peripheral blood basophils. Desloratadine (0.1 μM to 10 μM) is also shown to inhibit platelet-activating factor-induced eosinophil chemotaxis and TNF-α-induced eosinophil adhesion in eosinophils obtained from patients with allergic rhinitis or allergic asthma [1]. Desloratadine (1 μM-10 μM) dose-dependently inhibits the release of histamine and LTC4 from human basophils. Desloratadine (0.1 μM-10 μM) dose-dependently inhibits IL-13 secretion from basophils activated with IL-3 and PMA from human basophils. Desloratadine (10 μM) pretreatment results in a substantial decrease of the induced cytokine message in cultured basophils. Desloratadine (10 μM) pretreatment causes approximately an 80% reduction in the IL-4 message accumulated with anti-IgE activation in cultured basophils. Desloratadine (10 μM) also inhibits the histamine and IL-4 protein secreted into the supernatants of cultured basophils [2]. [3H]Desloratadine binds to the human histamine H1 receptor expressed in CHO cells with Kd of 1.1 nM. Desloratadine is 52, 57, 194, and 153 times more potent than cetirizine, ebastine, fexofenadine, and loratadine, respectively, in competition-binding studies [3].