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.

Cinnarizine is a piperazine derivative with antihistaminic, antiserotonergic, antidopaminergic, and calcium channel-blocking activities. It inhibits calcium translocation across the vestibular sensory cells in the ampullae and maintains endolymph flow by preventing constriction of the stria vascularis. It is currently used for the treatment of nausea, vomiting, and vertigo caused by Meniere’s disease and other vestibular disorders. Cinnarizine is also used for prevention and treatment of motion sickness. Chronic use of cinnarizine may induce extrapyramidal symptoms.

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.

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.

Flunarizine is a selective calcium entry blocker with calmodulin binding properties and histamine H1 / dopamine D2 blocking activity. It is not available in the US but marketed in other countries for prophylaxis of a migraine, occlusive peripheral vascular disease, the vertigo of central and peripheral origin, motion sickness and as an adjuvant in the therapy of epilepsy. The drug is also investigated for the treatment of schizophrenia.

Tramazoline is a sympathomimetic drug that is used in the form of tramazoline hydrochloride in nasal decongestant preparations. Tramazoline is an α-adrenergic receptor agonist that inhibits secretion of nasal mucus.

Thiazinamium is an anti-cholinergic phenothiazine deriva¬tive, which also has antihistaminic properties. Intramuscular injection of Thiazinamium induces considerable bronchodilatation, but inconsistent results have been obtained after oral administration. The bioavailability of oral Thiazinamium is only 2-3% of that occurring after intramuscular injection. Intrarectal Thiazinamium is slightly better absorbed (3-9%). The elimination half-life of the parenteral drug is short, being about 20 minutes in most patients. Thiazinamium has been available for the treatment of asthma since the early 1960s but currently withdrawn in most countries. Compared with inhaled ipratropium bromide, intramuscular Thiazinamium and intramuscular atropine were associated with 'extremely frequent side-effects’. Notable tachycardia occurred shortly after intramuscular injection of Thiazinamium in two trials. Dry mouth was reported as ‘frequent’ with oral Thiazinamium, and micturition problems of moderate severity affected 13% of patients.

Dibenzepin is a tricyclic antidepressant of the dibenzo-epine group. It is a selective noradrenaline uptake inhibitor, which exhibits in vitro and in vivo imipramine-like effects. It binds strongly to histamine H1 receptors in the brain and, to a lesser extent, to cholinergic receptors. The pharmacological profile of dibenzepin corresponds widely to its biochemical properties: histamine antagonism, tetrabenazine antagonism, potentiation of various noradrenergic effects and anticholinergic effects. Dibenzepin is only available in European countries for the treatment of depression.

Opipramol (Insidon, Pramolan, Ensidon, Oprimol) is an antidepressant and anxiolytic used in Germany and other European countries. Although it is a member of the tricyclic antidepressants, opipramol's primary mechanism of action is much different in comparison, it doesn’t represent a tricyclic antidepressant drug as it does not inhibit the neuronal uptake of norepinephrine and/or serotonin. Opipramol also acts as a low to moderate affinity antagonist for the D2, 5-HT2, H1, H2, and muscarinic acetylcholine receptors. H1 and H2 receptor antagonism account for its antihistamine effects, and muscarinic acetylcholine receptor antagonism is responsible for its anticholinergic properties. Opipramol was developed by Schindler and Blattner in 1961. Opipramol is typically used in the treatment of generalized anxiety disorder (GAD) and somatoform disorders. Its anxiolysis becomes prominent after only one to two weeks of chronic administration. Upon first commencing treatment, opipramol is rather sedating in nature due to its antihistamine properties, but this effect becomes less prominent with time. The therapy with Opipramol indicates an additional therapy with neuroleptics, hypnotics and tranquilizers (e.g. Barbiturates, Benzodiazepines). Therefore, it should be noted that some specific reactions, particularly CNS depressant effects could be intensified and an intensification of common side effects may occur. If necessary the dosage may be reduced. Co-administration with alcohol can cause stupor. MAO Inhibitors should be discontinued at least 14 days before the treatment with Opipramol. Concomitant use of Opipramol with β-blockers, antiarrhythmics (of class 1c), as well as drugs from tricyclic antidepressant group and preparations which influence the microsomal enzyme system, can lead to change in plasma concentration of these drugs. Co-administration of neuroleptics (example- haloperidol, risperidone) can increase the plasma concentration.