Dimetindene , also sold under the brand name Fenistil, is an
antihistamine
Antihistamines are drugs which treat allergic rhinitis, common cold, influenza, and other allergies. Typically, people take antihistamines as an inexpensive, generic (not patented) drug that can be bought without a prescription and provides re ...
/
anticholinergic
Anticholinergics (anticholinergic agents) are substances that block the action of the neurotransmitter called acetylcholine (ACh) at synapses in the central and peripheral nervous system.
These agents inhibit the parasympathetic nervous system ...
. It is a first generation selective
H1 antagonist
H1 antagonists, also called H1 blockers, are a class of medications that block the action of histamine at the H1 receptor, helping to relieve allergic reactions. Agents where the main therapeutic effect is mediated by negative modulation of h ...
. Dimetindene is an atypical first generation H1 antagonist as it only minimally passes across the
blood–brain barrier
The blood–brain barrier (BBB) is a highly selective semipermeable membrane, semipermeable border of endothelium, endothelial cells that prevents solutes in the circulating blood from ''non-selectively'' crossing into the extracellular fluid of ...
.
Dimetindene is also an
M2 receptor
The muscarinic acetylcholine receptor M2, also known as the cholinergic receptor, muscarinic 2, is a muscarinic acetylcholine receptor that in humans is encoded by the ''CHRM2'' gene. Multiple alternatively spliced transcript variants have been ...
antagonist.
It was patented in 1958 and came into medical use in 1960.
Medical use
Dimetindene is used orally and topically as an
antipruritic
Antipruritics, abirritants, or anti-itch drugs, are medications that inhibit the itching (Latin: ''pruritus'') often associated with sunburns, allergic reactions, eczema, psoriasis, chickenpox, fungal infections, insect bites and stings like those ...
.
It is used topically to treat skin irritations, such as insect bites. Dimetindene is also administered orally to treat allergies, such as
hay fever
Allergic rhinitis, of which the seasonal type is called hay fever, is a type of inflammation in the nose that occurs when the immune system overreacts to allergens in the air. Signs and symptoms include a runny or stuffy nose, sneezing, red, i ...
.
It is commonly
formulated as its
maleic acid
Maleic acid or ''cis''-butenedioic acid is an organic compound that is a dicarboxylic acid, a molecule with two carboxyl groups. Its chemical formula is HO2CCH=CHCO2H. Maleic acid is the ''cis''-isomer of butenedioic acid, whereas fumaric acid ...
salt
Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in the form of a natural crystalline mineral is known as rock salt or halite. Salt is present in vast quantitie ...
, dimethindene maleate.
Names
It is sold under the brand name
Fenistil Fenistil is a brand name for some over the counter medications distributed by GlaxoSmithKline and Novartis.
Products include:
* Fenistil Gel, containing dimetindene
* Fenistil Cold Sore Cream, containing penciclovir
* FeniHydrocort, containing cort ...
among others.
References
{{Muscarinic acetylcholine receptor modulators
H1 receptor antagonists
Indenes
Muscarinic antagonists
2-Pyridyl compounds