Sequifenadine is H1- and 5HT-serotonine receptor antagonist. It has an anti-histamine effect, not only blocking histamine receptors, but also reducing the content of histamine in tissues by accelerating its destruction by diamine oxidase. Sequifenadine did not demonstrate any significant sedative effect. It has a pronounced and prolonged antipruritic and antiexudative effect. It is indicated for the treatment of allergic rhinitis and conjunctivitis, pollinosis, urticaria, angioedema, allergic pruritic dermatosis, including atopic dermatitis. Adverse effects are: dry mouth, pain in the epigastric region, dyspepsia, increased appetite, headache, sleepiness.

Etymemazine (RP-6484), a phenothiazine derivative, is a sedative and neuroleptic agent. It is a histamine H₁-receptor antagonist. It was used to treat dementia. It was also used in veterinary.

Roxatidine is an histamine H2-receptor antagonist. Roxatidine is a potent and selective inhibitor of basal and stimulated gastric acid secretion through competitive blockade of H2-receptors. Total pepsin secretion is reduced in a dose-dependent manner. There is an independent mucosal protection action. Roxatidine is indicated for the treatment of peptic ulcer, gastro-oesophageal reflux disease, gastritis, upper gastrointestinal haemorrhage and Zollinger-Ellison syndrome also it can be used as a premedication before anaesthesia. Roxatidine possessed a robust estrogenic activity.

Medrylamine is an antihistamine agent. It was used topically. Medrylamine offers sure relief from allergic manifestations of varied and unknown etiologies

Osutidine (T-593) is a H2 receptor antagonist which was undergoing development by Toyama Chemical for the treatment of peptic/gastric and duodenal ulcers. It is a beta-hydroxyphenethylamine derivative with both antisecretory and cytoprotective properties. Osutidine inhibited the histamine-induced cAMP generation in a concentration-dependent manner. Osutidine suppressed the maximal response of the histamine-induced positive chronotropic response, indicating that the compound is unsurmountable H2-antagonists. The metabolism of Osutidine in humans may not differ from that of rodents and dogs. No clinically relevant accumulation occurred following repeated dosage. In the single oral and subcutaneous dose toxicity studies in rats, there were no dead animals. The oral LD50 value was greater than 5 g/kg for both sexes, and there was no abnormality in general signs. An oral formulation of the drug was in phase III clinical trials in Japan, however Toyama has dropped it from clinical development.

Iproheptine (Metron, Susat) is a vasoconstrictor, antihistamine, nasal decongestant marketed in Japan.

Dalcotidine is a histamine H2 receptor antagonist that demonstrated potent gastric mucosal protective activity on acute gastric lesions and duodenal ulcers. Dalcotidine was discontinued in phase III of clinical trials in Japan.

Chloropyramine is an antagonist of H1 histamine receptors. It is indicated for the treatment of various forms of allergic reactions. Chloropyramine is a drug capable of (1) inhibiting the biochemical function of VEGFR-3 and FAK, (2) inhibiting proliferation of a diverse set of cancer cell types in vitro, and (3) reducing tumor growth in vivo.

Mebhydrolin (INN) or mebhydroline is a histamine H1-receptor antagonist. It is not available in the United States, but it is available in various other countries under the brand names Bexidal and Diazolin. It is used for symptomatic relief of allergic symptoms caused by histamine release, including nasal allergies and allergic dermatosis.