GRANISETRON HYDROCHLORIDE PRESERVATIVE FREE
Clinical safety rating: safe
No significant drug interactions Generally well-tolerated with headache being the most common side effect.
Selective serotonin 5-HT3 receptor antagonist; blocks serotonin binding at vagal afferents in the gastrointestinal tract and area postrema of the central nervous system, inhibiting emetic reflex.
| Metabolism | Hepatic via CYP3A4 (major), CYP1A2 (minor); approximately 65% metabolized. |
| Excretion | Renal (48% unchanged, 18% as metabolites), fecal (34% as metabolites). |
| Half-life | Terminal elimination half-life: 4.1–6.1 hours in healthy adults; prolonged to 7.7–9.2 hours in elderly and in hepatic impairment. |
| Protein binding | 65% bound to plasma proteins (primarily albumin). |
| Volume of Distribution | Vd: 2.2–3.6 L/kg; distributes extensively into tissues, including the central nervous system. |
| Bioavailability | Oral: 60% (due to first-pass metabolism); IV: 100%. |
| Onset of Action | IV: 1–3 minutes; oral: 1–3 hours. |
| Duration of Action | IV: 24 hours; oral: up to 24 hours. Clinical effect lasts throughout chemotherapy cycle. |
2 mg orally once daily or 1 mg intravenously twice daily for prevention of chemotherapy-induced nausea and vomiting.
| Dosage form | INJECTABLE |
| Renal impairment | No dosage adjustment is required for patients with renal impairment, including those on hemodialysis. |
| Liver impairment | For Child-Pugh class A or B, no adjustment needed. For Child-Pugh class C, limited data; use with caution. |
| Pediatric use | For children 2-16 years: 10 mcg/kg intravenously every 12 hours, or 1 mg orally once daily (age 2-12) or 2 mg orally once daily (age 12-16). |
| Geriatric use | No specific dosage adjustment required; elderly patients may have increased sensitivity to side effects. |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
No significant drug interactions Generally well-tolerated with headache being the most common side effect.
| FDA category | Animal |
| Breastfeeding | Not known if granisetron is excreted in human milk. Caution should be exercised when administered to a nursing woman. M/P ratio not available. |
| Teratogenic Risk | Pregnancy Category B. Animal studies have not demonstrated fetal risk, but no adequate and well-controlled studies in pregnant women. Use only if clearly needed. |
■ FDA Black Box Warning
None.
| Common Effects | Headache |
| Serious Effects |
["Hypersensitivity to granisetron or any component of the formulation","Concurrent use of apomorphine (increased risk of profound hypotension and loss of consciousness)"]
| Precautions | ["Serotonin syndrome risk when used with other serotonergic drugs (e.g., SSRIs, SNRIs)","QT prolongation possible; caution in patients with pre-existing arrhythmias, electrolyte disturbances, or concomitant QT-prolonging drugs","Hypersensitivity reactions (including anaphylaxis) reported","Reduce dose in severe hepatic impairment (Child-Pugh score >10) to 10 mcg/kg IV"] |
Loading safety data…
| Fetal Monitoring | No specific monitoring required beyond standard pregnancy care; monitor for adverse effects such as headache, constipation, and QT prolongation. |
| Fertility Effects | No known effect on fertility. Animal studies have not shown impaired fertility. |