A comprehensive list of antihistamines: H1 receptor (part 1)

Alimemazine, also called trimeprazine, is a phenothiazine derivative, placing it in the same class as the more well known promethazine. It is used for a variety of purposes, including antipruritic (prevents itching), sedative, antiemetic, anxiety disorders, organic mood disorders and sleep disorders. It is a first generation H1 antagonist. It is not available for use in the US, but is available in many other countries, including several European countries, Japan, Taiwan, South Africa, Australia, New Zealand and throughout the Middle East.

Azatadine is a first generation H1 antagonist with structural similarities to loratadine. It is available as Zadine in India (note: Zadine is a brand name used in several countries for multiple drugs). It is used to treat allergic symptoms.

Bamipine is a first generation topical H1 antagonist used for itching and allergic rashes. It is sometimes combined with hydrocortisone and sold as a cream or gel. It is available in Austria, Germany and Poland.

Benztropine, also called benzatropine, is a first generation H1 antagonist. It is most commonly used in the treatment of Parkinson’s disease, and Parkinson-like symptoms, particularly tremors. It can also be used to treat dystonia. Benztropine is a widely acting medication. It also acts as a dopamine reuptake inhibitor, which can be helpful in treating narcolepsy and attention disorders, and a functional inhibitor of acid sphingomyelinase, which is sometimes used to treat depression. One study found that benztropine decreased symptoms and encouraged nerve re-myelination in MS patients.

Bepotastine is a non-sedating, second generation H1 antagonist. It is available as an oral and ophthalamic mediction in several Asian countries under the brand name Talion, with ophthalmic preparation only available in the US as Bepreve. Bepotastine has been well studied. In adult models, it inhibited histamine, antigen and PAF induced skin reactions, systemic shock, airway constriction and maintained appropriate vascular permeability. It may also inhibit leukotriene B4, NO production and substance P.

Brompheniramine is a first generation propylamine H1 antagonist. It is used for general allergic symptoms and is found over the counter in many countries. Additionally, it functions as a serotonin and norepinephrine reuptake inhibitor, giving it antidepressant properties. The first SSRI was derived from brompheniramine. It also potentiates the effects of opioid pain medication so less pain medication can be used.

Buclizine is an H1 antagonist derived from piperazine. It is mostly used for nausea. It is available in several countries, including India, Taiwan, Singapore and multiple European nations. In the UK, buclizine is available in a combination migraine medication, Migraleve.

Captodiame is an H1 antagonist derived from diphenhydramine. It is also a serotonin receptor antagonist and dopamine receptor agonist. It has antidepressant effects via a unique mechanism that raises brain-derived neurotrophic factor in the hypothalamus only. It can also mitigate CRF activity in the hypothalamus.

Carbinoxamine is an H1 antagonist readily available in many countries, including in the US. It is often combined with other medications, such as decongestants. It is used for urticarial, angioedema, dermatographism, hay fever and allergic rhinitis and conjunctivitis.

Chlorcyclizine is a first generation H1 antagonist derived from phenylpiperazine. It is used for general allergic symptoms and as an antiemetic. It also has local anesthetic properties and antagonizes serotonin receptors.