CYCLIZINE

US Approved OTC

First approved in 1953

Details

Stereochemistry	ACHIRAL
Molecular Formula	C18H22N2
Molecular Weight	266.3807
Optical Activity	NONE
Defined Stereocenters	0 / 0
E/Z Centers	0
Charge	0

SHOW SMILES / InChI

Structure Search

SMILES

CN1CCN(CC1)C(C2=CC=CC=C2)C3=CC=CC=C3

InChI

InChIKey=UVKZSORBKUEBAZ-UHFFFAOYSA-N

InChI=1S/C18H22N2/c1-19-12-14-20(15-13-19)18(16-8-4-2-5-9-16)17-10-6-3-7-11-17/h2-11,18H,12-15H2,1H3

HIDE SMILES / InChI

Molecular Formula	C18H22N2
Molecular Weight	266.3807
Charge	0
Count

Stereochemistry	ACHIRAL
Additional Stereochemistry	No
Defined Stereocenters	0 / 0
E/Z Centers	0
Optical Activity	NONE

Description
Sources: http://www.medicines.org.uk/EMC/medicine/14672/SPC/Valoid+Tablets/
Curator's Comment: description was created based on several sources, including https://www.ncbi.nlm.nih.gov/mesh/68003501

Cyclizine (cyclizine hydrochloride, Valoid®) is a histamine H1 antagonist of the piperazine class which is characterised by a low incidence of drowsiness. It possesses anticholinergic and antiemetic properties. The exact mechanism by which cyclizin (cyclizine hydrochloride, Valoid®) can prevent or suppress both nausea and vomiting from various causes is unknown. It increases lower oesophageal sphincter tone and reduces the sensitivity of the labyrinthine apparatus. It may inhibit the part of the midbrain known collectively as the emetic centre.

CNS Activity

Originator

Approval Year

Targets

Primary Target	Pharmacology	Condition	Potency
Histamine H1 receptor 316 Target ID: CHEMBL231 Sources: https://www.medicines.org.uk/emc/medicine/14672	Antagonist 2849		5.42 µM [IC50]

Conditions

Condition	Modality	Highest Phase	Product
Postoperative nausea and vomiting 31 Sources: https://www.medicines.org.uk/emc/medicine/14672	Preventing	Approved 8583	VALOID Approved Use Valoid is indicated for the prevention and treatment of nausea and vomiting including: • Motion sickness. • Nausea and vomiting caused by narcotic analgesics and by general anaesthetics in the post-operative period. • Vomiting associated with radiotherapy, especially for breast cancer since cyclizine does not elevate prolactin levels. Valoid may be of value in relieving vomiting and attacks of vertigo associated with Meniere's disease and other forms of vestibular disturbance. Launch Date 2005
Motion sickness 43 Sources: https://www.medicines.org.uk/emc/medicine/14672	Preventing	Approved 8583	VALOID Approved Use Valoid is indicated for the prevention and treatment of nausea and vomiting including: • Motion sickness. • Nausea and vomiting caused by narcotic analgesics and by general anaesthetics in the post-operative period. • Vomiting associated with radiotherapy, especially for breast cancer since cyclizine does not elevate prolactin levels. Valoid may be of value in relieving vomiting and attacks of vertigo associated with Meniere's disease and other forms of vestibular disturbance. Launch Date 2005
Vomiting associated with radiotherapy 4 Sources: https://www.medicines.org.uk/emc/medicine/14672	Preventing	Approved 8583	VALOID Approved Use Valoid is indicated for the prevention and treatment of nausea and vomiting including: • Motion sickness. • Nausea and vomiting caused by narcotic analgesics and by general anaesthetics in the post-operative period. • Vomiting associated with radiotherapy, especially for breast cancer since cyclizine does not elevate prolactin levels. Valoid may be of value in relieving vomiting and attacks of vertigo associated with Meniere's disease and other forms of vestibular disturbance. Launch Date 2005

C_max

Value	Dose	Co-administered	Analyte	Population
90 ng/mL EXPERIMENT https://www.sciencedirect.com/science/article/pii/0928098796001777	18.682 mg single, intravenous dose: 18.682 mg route of administration: Intravenous experiment type: SINGLE co-administered:		CYCLIZINE plasma	Homo sapiens population: HEALTHY age: ADULT sex: MALE food status: FASTED

AUC

Value	Dose	Co-administered	Analyte	Population
273.53 ng × h/mL EXPERIMENT https://www.sciencedirect.com/science/article/pii/0928098796001777	18.682 mg single, intravenous dose: 18.682 mg route of administration: Intravenous experiment type: SINGLE co-administered:		CYCLIZINE plasma	Homo sapiens population: HEALTHY age: ADULT sex: MALE food status: FASTED

T_1/2

Value	Dose	Co-administered	Analyte	Population
13.53 h EXPERIMENT https://www.sciencedirect.com/science/article/pii/0928098796001777	18.682 mg single, intravenous dose: 18.682 mg route of administration: Intravenous experiment type: SINGLE co-administered:		CYCLIZINE plasma	Homo sapiens population: HEALTHY age: ADULT sex: MALE food status: FASTED

Doses

Dose	Population	Adverse events
50 mg single, intravenous Recommended Dose: 50 mg Route: intravenous Route: single Dose: 50 mg Sources: https://pubmed.ncbi.nlm.nih.gov/12603456/	healthy, 34 years Health Status: healthy Age Group: 34 years Sex: F Sources: https://pubmed.ncbi.nlm.nih.gov/12603456/	Other AEs: Dystonic reaction... Other AEs: Dystonic reaction (1 patient) Sources: https://pubmed.ncbi.nlm.nih.gov/12603456/
80 mg/kg single, oral Lethal dose Dose: 80 mg/kg Route: oral Route: single Dose: 80 mg/kg Sources: https://pubmed.ncbi.nlm.nih.gov/7062687/	unhealthy, children and adults Health Status: unhealthy Age Group: children and adults Sex: unknown Sources: https://pubmed.ncbi.nlm.nih.gov/7062687/	Disc. AE: Death... AEs leading to discontinuation/dose reduction: Death (grade 5) Sources: https://pubmed.ncbi.nlm.nih.gov/7062687/
5 mg/kg single, oral Toxic dose Dose: 5 mg/kg Route: oral Route: single Dose: 5 mg/kg Sources: https://pubmed.ncbi.nlm.nih.gov/7062687/	unhealthy, children and adults Health Status: unhealthy Age Group: children and adults Sex: unknown Sources: https://pubmed.ncbi.nlm.nih.gov/7062687/	Other AEs: Convulsions... Other AEs: Convulsions (38 patients) Sources: https://pubmed.ncbi.nlm.nih.gov/7062687/

AEs

AE	Significance	Dose	Population
Dystonic reaction	1 patient	50 mg single, intravenous Recommended Dose: 50 mg Route: intravenous Route: single Dose: 50 mg Sources: https://pubmed.ncbi.nlm.nih.gov/12603456/	healthy, 34 years Health Status: healthy Age Group: 34 years Sex: F Sources: https://pubmed.ncbi.nlm.nih.gov/12603456/
Death	grade 5 Disc. AE	80 mg/kg single, oral Lethal dose Dose: 80 mg/kg Route: oral Route: single Dose: 80 mg/kg Sources: https://pubmed.ncbi.nlm.nih.gov/7062687/	unhealthy, children and adults Health Status: unhealthy Age Group: children and adults Sex: unknown Sources: https://pubmed.ncbi.nlm.nih.gov/7062687/
Convulsions	38 patients	5 mg/kg single, oral Toxic dose Dose: 5 mg/kg Route: oral Route: single Dose: 5 mg/kg Sources: https://pubmed.ncbi.nlm.nih.gov/7062687/	unhealthy, children and adults Health Status: unhealthy Age Group: children and adults Sex: unknown Sources: https://pubmed.ncbi.nlm.nih.gov/7062687/

Overview

CYP3A4	CYP2C9	CYP2D6	hERG
	inhibitor 2438	substrate 1388

OverviewOther

Other Inhibitor	Other Substrate	Other Inducer
	UGT1A1 479 UGT1A3 470 UGT1A4 399 UGT1A6 343 UGT1A7 249 UGT1A8 323 UGT1A9 423 UGT1A10 331 UGT2B4 278 UGT2B7 456 UGT2B10 131 UGT2B15 236 UGT2B17 237	MRP4 53 BCRP 101

Drug as perpetrator

Target	Modality	Activity
BCRP 985	inducer 1966 Sources: https://pubmed.ncbi.nlm.nih.gov/29691239/	yes
CYP2C9 2497	inhibitor 4027 Sources: https://livrepository.liverpool.ac.uk/15053/1/WilliamsonBet_Sep2013_15053.pdf#page=38 Page: 38.0	yes
MRP4 345	inducer 1966 Sources: https://pubmed.ncbi.nlm.nih.gov/29691239/	yes

Drug as victim

Target	Modality	Activity	Clinical evidence
UGT1A1 479	substrate 4014 Sources: https://pubmed.ncbi.nlm.nih.gov/29691239/	no
UGT1A10 331	substrate 4014 Sources: https://pubmed.ncbi.nlm.nih.gov/29691239/	no
UGT1A3 470	substrate 4014 Sources: https://pubmed.ncbi.nlm.nih.gov/29691239/	no
UGT1A4 399	substrate 4014 Sources: https://pubmed.ncbi.nlm.nih.gov/29691239/	no
UGT1A6 343	substrate 4014 Sources: https://pubmed.ncbi.nlm.nih.gov/29691239/	no
UGT1A7 249	substrate 4014 Sources: https://pubmed.ncbi.nlm.nih.gov/29691239/	no
UGT1A8 323	substrate 4014 Sources: https://pubmed.ncbi.nlm.nih.gov/29691239/	no
UGT1A9 423	substrate 4014 Sources: https://pubmed.ncbi.nlm.nih.gov/29691239/	no
UGT2B15 236	substrate 4014 Sources: https://pubmed.ncbi.nlm.nih.gov/29691239/	no
UGT2B17 237	substrate 4014 Sources: https://pubmed.ncbi.nlm.nih.gov/29691239/	no
UGT2B4 278	substrate 4014 Sources: https://pubmed.ncbi.nlm.nih.gov/29691239/	no
UGT2B7 456	substrate 4014 Sources: https://pubmed.ncbi.nlm.nih.gov/29691239/	no
UGT2B10 131	substrate 4014 Sources: https://pubmed.ncbi.nlm.nih.gov/29691239/	yes
CYP2D6 1388	substrate 4014 Sources: https://pubmed.ncbi.nlm.nih.gov/22209223/	yes	yes (pharmacogenomic study) Comment: The median overall metabolic ratio at steady state was 4.9 (3.8-9.2) and did vary with CYP2D6 genotype (P=0.02). Sources: https://pubmed.ncbi.nlm.nih.gov/22209223/

Sourcing

Vendor/Aggregator	ID	URL
ChEBI	CHEBI:3994	https://www.ebi.ac.uk/chebi/searchId.do?chebiId=CHEBI:3994
eMolecules	901706	https://www.emolecules.com/cgi-bin/more?vid=901706
ZINC	ZINC000019156872	http://zinc15.docking.org/substances/ZINC000019156872

PubMed

Title	Date	PubMed
Boosting blood flow: intravenous cyclizine in microsurgery.	2010-09	20811206
Optimal management of nausea and vomiting of pregnancy.	2010-08-04	21151729
Delayed ethylene glycol poisoning presenting with abdominal pain and multiple cranial and peripheral neuropathies: a case report.	2010-07-21	20663174
Palliative management of malignant bowel obstruction in terminally ill patient.	2010-05	21811356
Prescribing for migraine with the focus on selective 5HT1-receptor agonists: a pharmacy database analysis.	2010-05	20420788
Inappropriate prescribing in the hospitalized elderly patient: defining the problem, evaluation tools, and possible solutions.	2010-04-07	20396637
Neuropharmacology of vestibular system disorders.	2010-03	20808544
Morphine-induced hallucinations - resolution with switching to oxycodone: a case report and review of the literature.	2009-12-23	20062554
Drugs associated with more suicidal ideations are also associated with more suicide attempts.	2009-10-02	19798416
The cautious use of cyclizine in a patient with myasthenia gravis.	2009-10	19807233
Effect of fluid preloading on postoperative nausea and vomiting following laparoscopic cholecystectomy.	2009-07	20532102
Application of adsorptive voltammetry for the detection of sub-nano molar cyclizine in biological fluids and tablets using fast Fourier transform continuous cyclic voltammetry in a flowing system.	2009-04	19359790
Synthesis and in vitro antiproliferative activity of novel 1-benzhydrylpiperazine derivatives against human cancer cell lines.	2009-03	18973966
Management of postoperative nausea and vomiting: focus on palonosetron.	2009-02	19436621
A survey of post-craniotomy analgesia in British neurosurgical centres: time for perceptions and prescribing to change?	2009	19863401
The misuse/abuse of antihistamine antiemetic medication (cyclizine) by cancer patients.	2008-10	18718990
Mechanistic investigation of N,N-diethyl-4-(phenyl-piperidin-4-ylidenemethyl)-benzamide-induced insulin depletion in the rat and RINm5F cells.	2008-09	18539914
Management of Ménière's disease in general practice: adherence to the UK National Health Service 'Prodigy' guidelines.	2008-08	18039416
Chemotherapy-and cancer-related nausea and vomiting.	2008-01	18231647
Akathisia and an unusual symptomatic treatment: a case report.	2007-12	18073258
Routine multimodal antiemesis including low-dose perphenazine in an ambulatory surgery unit of a university hospital: a 10-year history. Supplement to: Eliminating postoperative nausea and vomiting in outpatient surgery with multimodal strategies including low doses of nonsedating, off-patent antiemetics: is "zero tolerance" achievable?	2007-06-12	17619779
Eliminating postoperative nausea and vomiting in outpatient surgery with multimodal strategies including low doses of nonsedating, off-patent antiemetics: is "zero tolerance" achievable?	2007-06-12	17619778
Characterization of antihistamine-human serum protein interactions by capillary electrophoresis.	2007-04-20	17339039
Systematic review on the recurrence of postoperative nausea and vomiting after a first episode in the recovery room - implications for the treatment of PONV and related clinical trials.	2006-12-13	17166262
Transient paralysis after administration of cyclizine.	2006-12	17090261
A comparison of cyclizine and granisetron alone and in combination for the prevention of postoperative nausea and vomiting.	2006-11	17042842
A preliminary ecotoxicity study of pharmaceuticals in the marine environment.	2006-11	16982534
Drugs for preventing postoperative nausea and vomiting.	2006-07-19	16856030
Use of intravenous cyclizine in cardiac chest pain.	2006-07	16794116
Prolonged extra-pyramidal side effects after discontinuation of haloperidol as an antiemetic.	2006-04	16764227
Best evidence topic report. Use of intravenous cyclizine in cardiac chest pain.	2006-01	16373808
Acute eosinophilic pneumonia caused by calcium stearate, an additive agent for an oral antihistaminic medication.	2006	17016002
Transient paralysis after administration of a single dose of cyclizine.	2005-12	16288623
An LC-MS-MS method for the determination of cyclizine in human serum.	2005-09-25	16054445
Effect of (+) or (-) camphorsulfonic acid additives to the mobile phase on enantioseparations of some basic drugs on a Chiralcel OD column.	2005-08-12	16078699
Antihistamines in the treatment of dermatitis.	2005-06-01	15926215
Cyclizine and droperidol have comparable efficacy and side effects during patient-controlled analgesia.	2005-03-02	15736352
Diluent choice for subcutaneous infusion: a survey of the literature and Australian practice.	2005-02	15798495
Percutaneous absorption of cyclizine and its alkyl analogues.	2005-02	15661496
Screening and semi-quantitative analysis of post mortem blood for basic drugs using gas chromatography/ion trap mass spectrometry.	2004-12-25	15556548
Outcome and patient acceptance of outpatient laparoscopic cholecystectomy.	2004-09-07	15347113
Spectrophotometric and LC determination of two binary mixtures containing antihistamins.	2004-09	15337437
Is intraperitoneal levobupivacaine with epinephrine useful for analgesia following laparoscopic cholecystectomy? A randomized controlled trial.	2004-08	15473621
Improving the acceptability of the atrial defibrillator for the treatment of persistent atrial fibrillation: the atrial defibrillator sedation assessment study (ADSAS).	2004-08	15262026
The Cyclimorph cough.	2004-06	15144309
Early analgesic effects of parecoxib versus ketorolac following laparoscopic sterilization: a randomized controlled trial.	2004-06	15121727
Effects of antihistaminics on locomotor activity in mice. Comparison with opiate and amphetamine-induced hyperactivity.	1991	1676005
Cyclizine-induced chorea. Observations on the influence of cyclizine on dopamine-related movement disorders.	1977-03	839234
Dimenhydrinate (Dramamine) abuse: hallucinogenic experiences with a proprietary antihistamine.	1972-02	5058102
Cyclizine anaphylaxis, when administered with propanidid.	1969-01	5762012

Patents

Sample Use Guides

In Vivo Use Guide

1 tablet (50 mg) orally, which may be repeated up to three times a day.

Route of Administration: Oral

In Vitro Use Guide

Cyclizine was tested for its effect on anti-IgE-induced histamine release from human lung fragments in vitro. IC50 value was 5.42 uM (0.14-20.44).

Substance Class	Chemical Created by `admin` on `Wed Apr 02 08:20:52 GMT 2025` Edited by `admin` on `Wed Apr 02 08:20:52 GMT 2025`
Record UNII	QRW9FCR9P2
Record Status	`Validated (UNII)`
Record Version

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Name

Type

Language

CYCLIZINE

Official Name

English

NSC-26608

Preferred Name

English

CYCLIZINE [MART.]

Common Name

English

CYCLIZINE [HSDB]

Common Name

English

CYCLIZINE [MI]

Common Name

English

1-(Diphenylmethyl)-4-methylpiperazine

Systematic Name

English

cyclizine [INN]

Common Name

English

CYCLIZINE [VANDF]

Common Name

English

Cyclizine [WHO-DD]

Common Name

English

PIPERAZINE, 1-(DIPHENYLMETHYL)-4-METHYL-

Systematic Name

English

Classification Tree Code System Code

WHO-ESSENTIAL MEDICINES LIST

8.4