Rupatadine is characterised as a non-sedating H1 anti-histamine and platelet-activating factor (PAF) receptor antagonist. Rupatadine is indicated for the treatment of allergic rhinitis and urticaria. Rupatadine is a safe and well tolerated drug in patients over 2 years old, with no central nervous system or cardiovascular effects and it can be taken with or without foods.

Dimebon (latrepirdine) is an orally available, small molecule, gamma carboline derivative that was developed and used in Russia as an over-the-counter oral antihistamine for allergy treatment since 1980s. In 1990s it was shown that Dimebon has promising potential in treating neurodegenerative diseases. In 2003, Medivation Inc acquired the rights to Dimebon. Medivation went public in December 2004, with Dimebon as the only drug in its pipeline. The product was being developed by Medivation and Pfizer as a treatment for early-stage Alzheimer's disease and Huntington's disease. However, development was discontinued by Medivation and Pfizer in early 2012. Dimebon inhibits alpha-Adrenergic receptors (alpha1A, alpha1B, alpha1D, and alpha2A), Histamine H1 and H2 receptors and Serotonin 5-HT2c, 5-HT5A, 5-HT6 receptors with high affinity. Dimebon may act by blocking NMDA receptors or voltage-gated Ca2+ channels and by preventing mitochondrial permeability pore transition.

Lafutidine is a novel histamine H2 antagonist with gastroprotective activity. Lafutidine exhibited potent and long-lasting H2 antagonism and prolonged antisecretion. In addition, lafutidine showed a gastroprotective effect against noxious agents-induced gastric mucosal damage through capsaicin-sensitive afferent nerves. Lafutidine showed antiulcer activities against acute ulcer models, prevented gastric ulcer relapse of acetic ulcer. Adverse events observed during clinical trials included constipation, diarrhea, drug rash, nausea, vomiting and dizziness.It also activates calcitonin gene-related peptide, resulting in the stimulation of nitric oxide (NO) and regulation of gastric mucosal blood flow, increases somatostatin levels also resulting in less gastric acid secretion, causes the stomach lining to generate more mucin, inhibits neutrophil activation thus preventing injury from inflammation, and blocks the attachment of Helicobacter pylori to gastric cells

Spaglumic acid (NAAG) is the β-aspartyl isoform of N-Acetyl-l-aspartylglutamate (isospaglumic Acid is N-(N-Acetyl-l-α-aspartyl)-l-glutamic acid). In eye drops, spaglumic acid is either a magnesium or sodium salt of N-Acetyl-l-aspartylglutamate. Spaglumic acid is a mast cell stabilizer. Thus it is used in allergic conditions such as allergic conjunctivitis. Specifically spaglumic acid is approved in Portugal under the brand name Naabak and in Greece under the brand name Naaxia for use in patients with allergic conjunctivitis. Spaglumic Acid is a peptide neurotransmitter and the third-most-prevalent neurotransmitter in the mammalian nervous system. It is a weak activator of NMDA receptors and a highly selective agonist for mGlu3 receptors. Spaglumic Acid is neuroprotective under non-hydrolysing conditions in vivo.

Mefenidramium is an active ingredient of the Danish drug Paradryl that was used to treat pruritus with varicella and as a palliative treatment of estival rhinitis in children.

Ebastine is an antihistamine which blocks H1-receptors through its carboxylic acid metabolite. Ebastine is indicated for the treatment of allergic rhinitis and chronic idiopathic urticaria.

Eprozinol inhibits bronchoconstriction by an action on histamine H1 receptors and has been used in the treatment of asthma and bronchitis. No significant changes in cAMP and cGMP levels are observed in guinea pig trachea, with eprozinol or isoprenaline, at doses capable of inducing relaxation. Eprozinol is only a very weak phosphodiesterase inhibitor, at large concentrations. The anti-bronchoconstrictor activities of eprozinol and isoprenaline with regard to histamine are directly additive and show absolutely no interference with one another. Propranolol is without effect on in vivo anti-bronchoconstrictor activity of eprozinol on tracheal musculature. It is concluded, that the mechanisms brought into play by eprozinol to exert anti-bronchoconstrictor and bronchorelaxant activity, are completely independent of the adrenergic system. In a retrospective study of 199 cases of accidental or intentional acute poisoning with eprozinol, eprazinone and zipeprol, collected at the Poison Control Center were seven cases of seizures, all after ingestion of eight times the therapeutic dose. They resolved rapidly and without recurrence with symptomatic treatment.

Bilastine is a new second generation H1-antihistamine recently approved for the symptomatic treatment of allergic rhinitis (AR) and chronic urticaria (CU). Bilastine is an H1 receptor inverse agonist. Bilastine also exerts anti-inflammatory activity by inhibiting the release of histamine, IL-4 and tumor necrosis factor (TNF)-α from human mast cells and granulocytes. Common side effects are headache and drowsiness.

Barmastine [bermastine, R 57959, ramastine], is an oral antihistamine agent which was being developed by Johnson & Johnson for use in asthma. Development was discontinued later.

Repirinast is an antiallergic drug developed and introduced into the market in Japan in 1987. It is a histamine release inhibitor. It has demonstrated effectiveness for treating bronchial asthma in humans.