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Details

Stereochemistry RACEMIC
Molecular Formula C18H19N3O
Molecular Weight 293.363
Optical Activity ( + / - )
Defined Stereocenters 0 / 1
E/Z Centers 0
Charge 0

SHOW SMILES / InChI
Structure of ONDANSETRON

SMILES

CN1C2=C(C3=C1C=CC=C3)C(=O)C(CN4C=CN=C4C)CC2

InChI

InChIKey=FELGMEQIXOGIFQ-UHFFFAOYSA-N
InChI=1S/C18H19N3O/c1-12-19-9-10-21(12)11-13-7-8-16-17(18(13)22)14-5-3-4-6-15(14)20(16)2/h3-6,9-10,13H,7-8,11H2,1-2H3

HIDE SMILES / InChI

Molecular Formula C18H19N3O
Molecular Weight 293.363
Charge 0
Count
MOL RATIO 1 MOL RATIO (average)
Stereochemistry RACEMIC
Additional Stereochemistry No
Defined Stereocenters 0 / 1
E/Z Centers 0
Optical Activity ( + / - )

Description

Ondansetron (ZOFRAN®) is a selective 5-HT3 receptor antagonist. It is effective in the treatment of nausea and vomiting caused by radiotherapy, anesthesia, surgery or cytotoxic chemotherapy drugs, including cisplatin, and has reported anxiolytic and neuroleptic properties. While its mechanism of action has not been fully characterized, ondansetron is not a dopamine-receptor antagonist. It is not certain whether ondansetron's antiemetic action is mediated centrally, peripherally, or in both sites. However, cytotoxic chemotherapy appears to be associated with release of serotonin from the enterochromaffin cells of the small intestine. The released serotonin may stimulate the vagal afferents through the 5-HT3 receptors and initiate the vomiting reflex.

CNS Activity

Originator

Approval Year

Targets

Primary TargetPharmacologyConditionPotency
8.31 null [pKi]

Conditions

ConditionModalityTargetsHighest PhaseProduct
Preventing
ZOFRAN
Preventing
ZOFRAN
Preventing
ZOFRAN

Cmax

ValueDoseCo-administeredAnalytePopulation
125.8 ng/mL
24 mg single, oral
ONDANSETRON plasma
Homo sapiens
194.4 ng/mL
24 mg single, oral
ONDANSETRON plasma
Homo sapiens
26.2 ng/mL
8 mg single, oral
ONDANSETRON plasma
Homo sapiens
42.7 ng/mL
8 mg single, oral
ONDANSETRON plasma
Homo sapiens
30.196 ng/mL
8 mg single, oral
ONDANSETRON plasma
Homo sapiens
32.096 ng/mL
8 mg single, oral
ONDANSETRON plasma
Homo sapiens

AUC

ValueDoseCo-administeredAnalytePopulation
224.155 ng*h/mL
8 mg single, oral
ONDANSETRON plasma
Homo sapiens
270.927999999999 ng*h/mL
8 mg single, oral
ONDANSETRON plasma
Homo sapiens
237.935 ng*h/mL
8 mg single, oral
ONDANSETRON plasma
Homo sapiens
293.491999999999 ng*h/mL
8 mg single, oral
ONDANSETRON plasma
Homo sapiens

T1/2

ValueDoseCo-administeredAnalytePopulation
4.7 h
24 mg single, oral
ONDANSETRON plasma
Homo sapiens
5.8 h
24 mg single, oral
ONDANSETRON plasma
Homo sapiens
3.1 h
8 mg single, oral
ONDANSETRON plasma
Homo sapiens
3.5 h
8 mg single, oral
ONDANSETRON plasma
Homo sapiens

Funbound

ValueDoseCo-administeredAnalytePopulation
27%
8 mg single, oral
ONDANSETRON plasma
Homo sapiens

Overview

OverviewOther

Other InhibitorOther SubstrateOther Inducer








Drug as perpetrator​

Drug as victim

Tox targets

PubMed

Sample Use Guides

In Vivo Use Guide
To prevent nausea and vomiting associated with cancer chemotherapy the recommended adult oral dosage of ondansetron (ZOFRAN®) is a single 24-mg tablet administered 30 minutes before the start of single-day highly emetogenic chemotherapy; for moderately emetogenic cancer chemotherapy the recommended adult oral dosage is one 8-mg ondansetron (ZOFRAN®) tablet given twice a day (every 12 hours) for 1 to 2 days after completion of chemotherapy: the first dose should be administered 30 minutes before the start of emetogenic chemotherapy, with a subsequent dose 8 hours after the first dose. To prevent nausea and vomiting associated with radiotherapy the recommended adult oral dosage is one 8-mg ondansetron (ZOFRAN®) tablet given 3 times a day; for total body irradiation, one 8-mg ondansetron (ZOFRAN®) tablet should be administered 1 to 2 hours before each fraction of radiotherapy administered each day; for single high-dose fraction radiotherapy to the abdomen, one 8-mg ondansetron (ZOFRAN®) tablet should be administered 1 to 2 hours before radiotherapy, with subsequent doses every 8 hours after the first dose for 1 to 2 days after completion of radiotherapy; for daily fractionated radiotherapy to the abdomen, one 8-mg ondansetron (ZOFRAN®) tablet should be administered 1 to 2 hours before radiotherapy, with subsequent doses every 8 hours after the first dose for each day radiotherapy is given. To prevent postoperative nausea and vomiting the recommended adult oral dosage is 16 mg given as two 8-mg ondansetron (ZOFRAN®) tablets 1 hour before induction of anesthesia.
Route of Administration: Oral
In Vitro Use Guide
On the isolated vagus nerve and superior cervical ganglion of the rat, R,S-GR38032F (ondansetron) behaved as a reversible competitive antagonist of 5-HT-induced depolarization with pKB values of 8.61+/-0.08 (n=19) and 8.13+/-0.07 (n=16), respectively. The resolved R- and S-isomers of GR38032F were approximately equipotent as 5-HT antagonists on the rat vagus nerve: the pKB values were 8.95+/-0.05 (n=16) and 8.63+/-0.08 (n=17), respectively. R,S-GR38032F was also an effective antagonist of 5-HT on the rabbit isolated vagus nerve: in this case the pKB value was 9.40+/-0.14 (n=4).
Substance Class Chemical
Record UNII
4AF302ESOS
Record Status Validated (UNII)
Record Version