Histamine receptor antagonists disease

Several histamine receptor antagonists are effective in treating motion sickness, Meniere s disease, morning sickness, uraemia and postoperative vomiting. They are not effective against cytotoxics. Antagonists with... 

Ranitidine is a histamine receptor antagonist. It acts essentially on the H2 receptor and blocks acid production. Ranitidine is used in the treatment and prevention of ulcers, NSAID-induced ulcers, Zollinger-Ellison syndrome and gastro-oesophageal reflux disease. 

Nizatidine, a histamine-receptor antagonist (300 mg once daily at bedtime), is indicated in the management of duodenal ulcer, benign gastric ulcer, and gastroesophageal reflux disease (see also Table 10). 

Histamine produces its pharmacological actions by three subtypes of receptors the postsynaptic Hi and H2 receptors and the presynaptic H3 receptor. The H3 receptor is mainly located in the central nervous system (CNS), where it acts as an inhibitory autoreceptor in the central histaminergic neuronal pathways [176]. A number of therapeutic applications have been proposed for selective H3 receptor antagonists, including several CNS disorders such as Alzheimer s disease. Attention Deficit Hyperactivity Disorder, Schizophrenia, or for enhancing memory or obesity control. 

Intravenous histamine-2-receptor antagonists such as ranitidine, famotidine, and cimetidine are compatible with PN and can be added to the daily PN for prevention of stress-related mucosal damage and peptic ulcer disease. This provides a continuous acid suppression and reduces nursing time by avoiding intermittent scheduled infusions. 

This lack of complete effectiveness led to the hypothesis that a second type of histamine receptor existed. In 1972, Black et al. (55) discovered a new series of antagonists which they called H2 receptor blockers. Burimamide was the first highly effective H2 blocker, but it was poorly absorbed orally. The modified compound, metiamide, had better absorption but was found to cause granulocytopenia (57.58). Finally, cimetidine was tested and found to be a potent and relatively non-toxic antagonist (59). Cimetidine is now widely used clinically to treat duodenal ulcers, Zollinger-Ellison Syndrome and other gastric hypersecretory diseases (32). 

The histamine H4-receptor which was discovered in 2001 has been shown to have a role in chemo-taxis and mediator release in various types of immune cells including mast cells, eosinophils, dendritic cells and T cells. H4-receptor antagonists have been shown to have anti-inflammatory properties and efficacy in a number of disease models, such as those for asthma and colitis in vivo. Cinnarizine has a high affinity for the H4-receptor. Recently other H4-receptor antagonists have been developed with high receptor affinity and specificity. The first few studies into the function of H4-receptors suggested... 

It took about fifteen years after the role of histamine in allergic diseases had been established before the first clinically usefiil antihistamine was available in the late thirties. When the H2 receptor had been defined, it took less time until the H2 antagonist cimetidine was ready for clinical use. 

ZacnyJ, Zamakhshary M, Sketris I, et al. Systematic review the efficacy of intermittent and on-demand therapy with histamine H2-receptor antagonists or proton pump inhibitors for gastro-esophageal reflux disease patients. Aliment Pharmacol Ther. 2005 21 1299-1312. 

Effects of histamine on blood pressure and heart rate in humans. Histamine was infused at 40 u g/kg/h for 5 minutes as shown at the top of the panel. (Modified and reproduced, with permission, from Torsoli A, Lucchelli PE, Brimblecombe RW [editors] H-Antagonists H2 Receptor Antagonists in Peptic Ulcer Disease and Progress in Histamine Research. Excerpta Medica, 1980.)... 

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