Article: Granisetron

Granisetron
Systematic (IUPAC) name
1-methyl-N-(9-methyl-9-azabicyclo[3.3.1]non-3-yl)- indazole-3-carboxamide
Identifiers
CAS number	109889-09-0
ATC code	A04AA02
PubChem	3510
DrugBank	APRD01002
Chemical data
Formula	C18H24N4O
Mol. weight	312.41 g/mol
Pharmacokinetic data
Bioavailability	60%
Protein binding	65%
Metabolism	Hepatic
Half life	3–14 hours
Excretion	Renal 11–12%, faecal 38%
Therapeutic considerations
Pregnancy cat.	B1 (Au),
Legal status	S4 (Au), POM (UK), ℞-only (U.S.)
Routes	Oral, intravenous

Granisetron is a serotonin 5-HT₃ receptor antagonist used to treat nausea and vomiting following chemotherapy. Its main affect is to reduce the activity of the vagus nerve, which is a nerve that activates the vomiting center in the medulla oblongata. It does not have much effect on vomiting due to motion sickness. This drug does not have any effect on dopamine receptors or muscarinic receptors.

Granisetron was developed by chemists working at the British drug company Beecham around 1988 and is expected to go generic in 2007/2008. It is produced by Roche Laboratories under the trade name Kytril®. The drug was approved in the United Kingdom in 1991 and in United States in 1994 by the FDA.

Granisetron breaks down slowly, staying in the body for a long time. One dose usually lasts 4 to 9 hours and is usually administered once or twice daily. This drug is removed from the body by the liver and kidneys.

Clinical Uses

• Chemotherapy-induced nausea and vomiting
  • 5-HT₃ receptor antagonists are the primary drugs used to treat and prevent chemotherapy-induced nausea and vomiting. Many times they are given intravenously about 30 minutes before beginning therapy.
• Post-operative and post-radiation nausea and vomiting
• Is a possible therapy for nausea and vomiting due to acute or chronic medical illness or acute gastroenteritis
• Treatment of Cyclic vomiting syndrome although there are no formal trials to confirm efficacy.

Adverse Effects

Granisetron is a well-tolerated drug with few side effects. Headache, dizziness, and constipations are the most commonly reported side effects associated with its use. There have been no significant drug interactions reported with this drug's use. It is broken down by the liver's cytochrome P450 system and it has little effect on the metabolism of other drugs broken down by this system.