Two medicines, side by side
Granisetron vs ondansetron
Granisetron and ondansetron are both labeled for nausea and vomiting. Drugs@FDA records approvals of granisetron since 1993 and of ondansetron since 1991. Pharmacies paid $1.31 per granisetron HCl 1 mg tablet and $0.0582 per ondansetron HCl 4 mg tablet (NADAC, October 7, 2026); the strengths differ, so the two prices are not like for like. Granisetron's other strengths are brand-only: $685.85 per Sancuso 3.1 mg/24 hr patch. How each works, in its label's words: Granisetron, “Granisetron is a selective 5-hydroxytryptamine 3 (5-HT 3 ) receptor antagonist with little or no affinity for other serotonin receptors, including 5-HT 1 ; 5-HT 1A ; 5-HT 1B/C ; 5-HT 2 ; …”; Ondansetron, “Ondansetron is a selective 5‑HT 3 receptor antagonist.”
Check it at the source: the granisetron FDA label on DailyMed (effective August 31, 2017); the ondansetron FDA label on DailyMed (effective January 8, 2026).
Highlights of the granisetron record
Granisetron (Kytril) · label of August 31, 2017
Used for
From the label: indicationsGranisetron hydrochloride injection is a serotonin-3 (5-HT 3 ) receptor antagonist indicated for: • The prevention of nausea and/or vomiting associated with initial and repeat courses of emetogenic cancer therapy, including high-dose cisplatin. • The prevention and treatment of postoperative nausea and vomiting in adults. […]
On the market
- Earliest approval on file
- December 29, 1993
- Generic labelers
- 8 labelers
- Pharmacy cost
- $1.31 per tablet
Supply and safety
- Shortage
- No current entry
- Recalls
- 1
Highlights of the ondansetron record
Ondansetron (Zofran) · label of January 8, 2026
Used for
From the label: indicationsOndansetron is indicated for the prevention of nausea and vomiting associated with: • highly emetogenic cancer chemotherapy, including cisplatin greater than or equal to 50 mg/m 2 • initial and repeat courses of moderately emetogenic cancer chemotherapy • radiotherapy in patients receiving either total body irradiation, single high-dose fraction to the abdomen, or daily fractions to the abdomen Ondansetron is also indicated for the prevention of postoperative nausea and/or vomiting. […]
On the market
- Earliest approval on file
- January 4, 1991
- Generic labelers
- 77 labelers
- Pharmacy cost
- $0.0582 per tablet
Supply and safety
- Shortage
- No current entry
- Recalls
- 15
Source: FDA drug labels via openFDA (Granisetron label of August 31, 2017, Ondansetron label of January 8, 2026); NDC Directory, Drugs@FDA, NADAC, FDA shortages and recalls (October 8, 2026)
How do granisetron and ondansetron differ on the record?
How each works, in its label's words: Granisetron, “Granisetron is a selective 5-hydroxytryptamine 3 (5-HT 3 ) receptor antagonist with little or no affinity for other serotonin receptors, including 5-HT 1 ; 5-HT 1A ; 5-HT 1B/C ; 5-HT 2 ; …”; Ondansetron, “Ondansetron is a selective 5‑HT 3 receptor antagonist.”
Both are in FDA's class serotonin-3 receptor antagonists.
Generics: granisetron since 2007; ondansetron since 2006 (Drugs@FDA).
| Granisetron | Ondansetron | |
|---|---|---|
| Labeled for | Nausea and vomiting | Nausea and vomiting |
| Pharmacologic class | Serotonin-3 Receptor Antagonist | Serotonin-3 Receptor Antagonist |
| How it works (label) | Granisetron is a selective 5-hydroxytryptamine 3 (5-HT 3 ) receptor antagonist with little or no affinity for other serotonin receptors, including 5-HT 1 ; 5-HT 1A ; 5-HT 1B/C ; 5-HT 2 ; for alpha 1 -, alpha 2 - or beta-adrenoreceptors; … | Ondansetron is a selective 5‑HT 3 receptor antagonist. While its mechanism of action has not been fully characterized, ondansetron is not a dopamine‑receptor antagonist. |
| Half-life (label) | n/a | n/a |
| Earliest approval on file (Drugs@FDA) | December 29, 1993 | January 4, 1991 |
| First generic approved | December 31, 2007 | November 22, 2006 |
| Generic labelers (NDC) | 8 labelers | 77 labelers |
| Pharmacy cost (NADAC, each one's most listed form; strengths differ) | $1.31 per tablet (Granisetron HCl 1 mg tablet) | $0.0582 per tablet (Ondansetron HCl 4 mg tablet) |
| 12-month price change | -19% | -14% |
| Boxed warning | No | No |
| Shortage now | No current entry | No current entry |
| Recalls recorded | 1 | 15 |
| FAERS reports (a report is not proof of cause; counts follow how widely a medicine is used) | 12,067 | 121,842 |
| DEA schedule | none | none |
Source: Drugs@FDA, FDA NDC Directory, CMS NADAC of October 7, 2026, FDA shortages and recalls, FAERS via openFDA (FDA files October 8, 2026)
What do the labels say about using others of their kind?
Granisetron label, drug interactionsSerotonin syndrome (including altered mental status, autonomic instability, and neuromuscular symptoms) has been described following the concomitant use of 5-HT 3 receptor antagonists and other serotonergic drugs, including selective serotonin reuptake inhibitors (SSRIs) and serotonin and norepinephrine reuptake Inhibitors (SNRIs) [see Warnings and Precautions (5.4) ].
Ondansetron label, drug interactionsDRUG INTERACTIONS 7.1 Serotonergic Drugs Serotonin syndrome (including altered mental status, autonomic instability, and neuromuscular symptoms) has been described following the concomitant use of 5-HT 3 receptor antagonists and other serotonergic drugs, including SSRIs and SNRIs.
Source: FDA drug labels via openFDA
What next?
- Alternatives to granisetron
- every medicine labeled for the same conditions