Cyproheptadine
Encyclopedia
Cyproheptadine sold under the brand name Periactin, is a first-generation antihistamine
with additional anticholinergic
, antiserotonergic, and local anesthetic
properties.
(or inverse agonist
depending on the site in question) of the following receptor
s, listed in order of potency
from greatest to least (Ki):
It also has weak but likely negligible affinity for the following sites (Ki):
Additionally, cyproheptadine possesses calcium channel-blocking
and local anesthetic
properties.
, cyproheptadine causes drowsiness, as is common with first-generation antihistamines.
Research has shown a suppression of growth hormone
with doses of 8–12 mg per day taken for 5 days.
Other common side effects include:
s as an appetite stimulant and as an adjunct in the treatment of asthma
. Possible adverse effects include excitement and aggressive behavior.
The elimination half-life of cyproheptadine in cats is 12 hours. Cyproheptadine has been used successful in treatment of Pituitary Pars Intermedia Dysfunction (PPID) in horses.
Antihistamine
An H1 antagonist is a histamine antagonist of the H1 receptor that serves to reduce or eliminate effects mediated by histamine, an endogenous chemical mediator released during allergic reactions...
with additional anticholinergic
Anticholinergic
An anticholinergic agent is a substance that blocks the neurotransmitter acetylcholine in the central and the peripheral nervous system. An example of an anticholinergic is dicycloverine, and the classic example is atropine....
, antiserotonergic, and local anesthetic
Local anesthetic
A local anesthetic is a drug that causes reversible local anesthesia, generally for the aim of having local analgesic effect, that is, inducing absence of pain sensation, although other local senses are often affected as well...
properties.
Indications
- Cyproheptadine is used to treat allergic reactions (specifically hay feverHay FeverHay Fever is a comic play written by Noël Coward in 1924 and first produced in 1925 with Marie Tempest as the first Judith Bliss. Laura Hope Crews played the role in New York...
).
- Has shown effectiveness in the treatment of nightmares including nightmares related to post traumatic stress disorder.
- Has been used in the management of moderate to severe cases of serotonin syndromeSerotonin syndromeSerotonin syndrome is a potentially life-threatening adverse drug reaction that may occur following therapeutic drug use, inadvertent interactions between drugs, overdose of particular drugs, or the recreational use of certain drugs...
(a complex of symptoms associated with the use of serotonergicSerotonergicSerotonergic or serotoninergic means "related to the neurotransmitter serotonin". A synapse is serotonergic if it uses serotonin as its neurotransmitter...
drugs, such as selective serotonin reuptake inhibitorSelective serotonin reuptake inhibitorSelective serotonin re-uptake inhibitors or serotonin-specific reuptake inhibitor are a class of compounds typically used as antidepressants in the treatment of depression, anxiety disorders, and some personality disorders. The efficacy of SSRIs is disputed...
s and monoamine oxidase inhibitors), and in the disease carcinoidCarcinoidCarcinoid is a slow-growing type of neuroendocrine tumor, originating in the cells of the neuroendocrine system.In 2000, the World Health Organization redefined "carcinoid", but this new definition has not been accepted by all practitioners. This has led to some complexity in distinguishing...
in which serotonin is overproduced by tumor cells.
- Can also be used as a preventive measure against migraine in children and adolescents.
- Can relieve SSRI-induced sexual dysfunction and drug-induced hyperhydrosis (excessive sweating).
- Also used in the treatment of cyclical vomiting syndrome and to stimulate the appetite.
Pharmacology
Cyproheptadine is known to be an antagonistReceptor antagonist
A receptor antagonist is a type of receptor ligand or drug that does not provoke a biological response itself upon binding to a receptor, but blocks or dampens agonist-mediated responses...
(or inverse agonist
Inverse agonist
In the field of pharmacology, an inverse agonist is an agent that binds to the same receptor as an agonist but induces a pharmacological response opposite to that agonist....
depending on the site in question) of the following receptor
Receptor (biochemistry)
In biochemistry, a receptor is a molecule found on the surface of a cell, which receives specific chemical signals from neighbouring cells or the wider environment within an organism...
s, listed in order of potency
Potency (pharmacology)
In the field of pharmacology, potency is a measure of drug activity expressed in terms of the amount required to produce an effect of given intensity. A highly potent drug evokes a larger response at low concentrations, while a drug of lower potency evokes a small response at low concentrations...
from greatest to least (Ki):
- H1H1 receptorThe H1 receptor is a histamine receptor belonging to the family of Rhodopsin like G-protein-coupled receptors. This receptor, which is activated by the biogenic amine histamine, is expressed throughout the body, to be specific, in smooth muscles, on vascular endothelial cells, in the heart, and in...
(~0.05 nM) > 5-HT2A5-HT2A receptorThe mammalian 5-HT2A receptor is a subtype of the 5-HT2 receptor that belongs to the serotonin receptor family and is a G protein-coupled receptor . This is the main excitatory receptor subtype among the GPCRs for serotonin , although 5-HT2A may also have an inhibitory effect on certain areas such...
(~2 nM) ≈ 5-HT2B5-HT2B receptor5-hydroxytryptamine receptor 2B, also known as HTR2B, is a 5-HT2 receptor, but also denotes the human gene encoding it.-Function:...
(~1.5 nM) ≈ 5-HT2C5-HT2C receptorThe 5-HT2C receptor is a subtype of 5-HT receptor that binds the endogenous neurotransmitter serotonin . It is a G protein-coupled receptor that is coupled to Gq/G11 and mediates excitatory neurotransmission. HTR2C denotes the human gene encoding for the receptor, that in humans is located at the...
(~2 nM) > mAChMuscarinic acetylcholine receptorMuscarinic receptors, or mAChRs, are acetylcholine receptors that form G protein-coupled in the plasma membranes of certain neurons and other cells...
(M1Muscarinic acetylcholine receptor M1The muscarinic acetylcholine receptor M1, also known as the cholinergic receptor, muscarinic 1, is a muscarinic receptor.This receptor is found mediating slow EPSP at the ganglion in the postganglionic nerve, is common in exocrine glands and in the CNS.It is predominantly found bound to G proteins...
-M5Muscarinic acetylcholine receptor M5The human muscarinic acetylcholine receptor M5 which is encoded by the gene is a member of the G protein-coupled receptor superfamily of integral membrane proteins. Binding of the endogenous ligand acetylcholine to the M5 receptor triggers a number of cellular responses such as adenylate cyclase...
; ~7-12 nM) ≈ D3 (~8 nM)
It also has weak but likely negligible affinity for the following sites (Ki):
- 5-HT1A5-HT1A receptorThe 5-HT1A receptor is a subtype of 5-HT receptor that binds the endogenous neurotransmitter serotonin . It is a G protein-coupled receptor that is coupled to Gi/Go and mediates inhibitory neurotransmission...
(~60-100 nM) ≈ α1-adrenergicAlpha-1 adrenergic receptorThe alpha-1 adrenergic receptor is a G protein-coupled receptor associated with the Gq heterotrimeric G-protein. It consists of three highly homologous subtypes, including α1A-, α1B-, and α1D-adrenergic...
(?? nM) ≈ α2-adrenergicAlpha-2 adrenergic receptorThe alpha-2 adrenergic receptor is a G protein-coupled receptor associated with the Gi heterotrimeric G-protein. It consists of three highly homologous subtypes, including α2A-, α2B-, and α2C-adrenergic. Some species other than humans express a fourth α2D-adrenergic receptor as well...
(?? nM) > 5-HT65-HT6 receptorThe 5-HT6 receptor is a subtype of 5-HT receptor that binds the endogenous neurotransmitter serotonin . It is a G protein-coupled receptor that is coupled to Gs/Go and mediates excitatory neurotransmission. HTR6 denotes the human gene encoding for the receptor.-Distribution:The 5-HT6 receptor is...
(~135-150 nM) ≈ 5-HT75-HT7 receptorThe 5-HT7 receptor is a member of the GPCR superfamily of cell surface receptors and is activated by the neurotransmitter serotonin The 5-HT7 receptor is coupled to Gs and is expressed in a variety of human tissues, particularly in the brain, the gastrointestinal tract, and in various...
(~125 nM) ≈ D1 (~115 nM) ≈ D2 (~115 nM) > 5-HT35-HT3 receptorThe 5-HT3 receptor is a member of the superfamily of ligand-gated ion channels, a superfamily that also includes the neuronal nicotinic acetylcholine receptors , and the inhibitory neurotransmitter receptors for GABA and glycine...
(~250 nM) ≈ NETNorepinephrine transporterThe norepinephrine transporter , also known as solute carrier family 6 member 2 , is a protein that in humans is encoded by the SLC6A2 gene....
(~300 nM)
Additionally, cyproheptadine possesses calcium channel-blocking
Calcium channel blocker
A calcium channel blocker is a chemical that disrupts the movement of calcium through calcium channels.CCB drugs devised to target neurons are used as antiepileptics. However, the most widespread clinical usage of calcium channel blockers is to decrease blood pressure in patients with...
and local anesthetic
Local anesthetic
A local anesthetic is a drug that causes reversible local anesthesia, generally for the aim of having local analgesic effect, that is, inducing absence of pain sensation, although other local senses are often affected as well...
properties.
Pharmacokinetics
Cyproheptadine is well-absorbed following oral ingestion, with peak plasma levels occurring after 1-3 hours. Its half-life when taken orally is approximately 8 hours.Adverse effects
While not specifically used as a sedativeSedative
A sedative or tranquilizer is a substance that induces sedation by reducing irritability or excitement....
, cyproheptadine causes drowsiness, as is common with first-generation antihistamines.
Research has shown a suppression of growth hormone
Growth hormone
Growth hormone is a peptide hormone that stimulates growth, cell reproduction and regeneration in humans and other animals. Growth hormone is a 191-amino acid, single-chain polypeptide that is synthesized, stored, and secreted by the somatotroph cells within the lateral wings of the anterior...
with doses of 8–12 mg per day taken for 5 days.
Other common side effects include:
- Dizziness
- Blurred vision
- Constipation
- Dry mouth, throat, or nose
- Excitability
- Nausea
- Nervousness
- Restlessness
Veterinary use
Cyproheptadine is used in catCat
The cat , also known as the domestic cat or housecat to distinguish it from other felids and felines, is a small, usually furry, domesticated, carnivorous mammal that is valued by humans for its companionship and for its ability to hunt vermin and household pests...
s as an appetite stimulant and as an adjunct in the treatment of asthma
Asthma
Asthma is the common chronic inflammatory disease of the airways characterized by variable and recurring symptoms, reversible airflow obstruction, and bronchospasm. Symptoms include wheezing, coughing, chest tightness, and shortness of breath...
. Possible adverse effects include excitement and aggressive behavior.
The elimination half-life of cyproheptadine in cats is 12 hours. Cyproheptadine has been used successful in treatment of Pituitary Pars Intermedia Dysfunction (PPID) in horses.