Gemcitabine
2,2'-difluorodeoxycytidine hydrochloride
Also known as: Gemzar · Abine · Antoril · Gemcite · Gemtrol · dFdC · LY-288022 · 2,2'-diflurodeoxycytidine · Gemcitabina · Gemcitabinum
Reviewed by the VetSheet Veterinary TeamUpdated Apr 5, 2026Evidence-based veterinary reference
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Dosing by species
🌎 NA — North America🌍 EU — Europe
Dogs
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Carcinomas (in combination with carboplatin) | 2 mg/kg IV over 20-30 minutes | IV | no more than once every 7 days | — | 🌎 NA |
| Bladder urothelial carcinoma, lymphoma, and various carcinomas (High dose) | 800-900 mg/m2 | IV | every 7-14 days | for 4 doses | 🌍 EU |
| Bladder urothelial carcinoma, lymphoma, and various carcinomas (Low dose) | 25-50 mg/m2 | IV | once or twice a week | — | 🌍 EU |
| Carcinomas (Combination therapy) | 2 mg/kg | IV | every 7 days | — | 🌍 EU |
| Advanced solid tumors | Escalating doses per protocol | IV | single administration or per protocol | — | 🌍 EU |
- Carcinomas (in combination with carboplatin): Doses have ranged widely from 45 mg/m2-800 mg/m2 depending on the study.
- Bladder urothelial carcinoma, lymphoma, and various carcinomas (High dose): Administer over 20-60 minutes.
- Bladder urothelial carcinoma, lymphoma, and various carcinomas (Low dose): Administer over 20-60 minutes as per protocols.
- Carcinomas (Combination therapy): Administer over 20-30 minutes (in 0.9% NaCl) combined with carboplatin.
- Advanced solid tumors: Phase 1 dose-escalation trial.
Cats
| Indication | Dose | Route | Frequency | Duration | Region |
|---|---|---|---|---|---|
| Carcinomas (in combination with carboplatin) | 2 mg/kg IV over 20-30 minutes | IV | no more than once every 7 days | — | 🌎 NA |
| Exocrine pancreatic carcinoma (Low dose) | 20-25 mg/m2 or 2 mg/kg | IV | every 7 days | — | 🌍 EU |
- Carcinomas (in combination with carboplatin): Doses have ranged widely from 45 mg/m2-800 mg/m2 depending on the study.
- Exocrine pancreatic carcinoma (Low dose): Administer as a 20 minute IV infusion.
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Gemcitabine is a synthetic pyrimidine nucleoside analog used as an antineoplastic agent.
- Veterinary Use: Currently considered investigational with limited clinical data. It shows potential as a radiosensitizer for non-resectable tumors or as part of combination chemotherapy protocols (e.g., with carboplatin).
- Human Use: Efficacious in treating pancreatic, small-cell lung, bladder, and soft tissue carcinomas, as well as lymphoma.
Clinical Pearl: Due to its high cost and significant myelosuppressive potential, its use in veterinary medicine is typically reserved for specialized oncology practices.
Mechanism of action
Gemcitabine is a cell-cycle phase-specific antimetabolite that acts primarily during the S phase (DNA synthesis) and blocks progression through the G1/S-phase boundary.
- It is transported intracellularly and phosphorylated to dFdCMP, then to active diphosphate (dFdCDP) and triphosphate (dFdCTP) metabolites.
- dFdCDP inhibits ribonucleotide reductase, depleting the cellular pool of deoxynucleotides required for DNA synthesis.
- dFdCTP competes with endogenous deoxycytidine triphosphate (dCTP) for incorporation into the elongating DNA strand. Once incorporated, it causes DNA chain termination and subsequent apoptosis.
Safety & warnings
Contraindications
- Known hypersensitivity to gemcitabine
- Pre-existing bone marrow suppression
Adverse effects
- Myelosuppression (neutropenia and thrombocytopenia; nadir at 3-7 days)
- Mild to moderate gastrointestinal toxicity
- Retinal hemorrhage
- Myelosuppression (neutropenia, thrombocytopenia, anemia)
- Gastrointestinal toxicity (vomiting, diarrhea, anorexia)
- Retinal haemorrhage
- Treatment-related mortality (due to severe complications)
Precautions
Use with caution in patients with diminished renal or hepatic function. FDA Category D for pregnancy (evidence of fetal risk). Handle with standard cytotoxic safety precautions.
Drug interactions
Additive toxic effects (myelosuppression, GI toxicity)
Monitoring
- CBC before each treatment
- Fundic exam weekly while on therapy
- Baseline renal and hepatic function prior to therapy, and periodically thereafter
- Complete Blood Count (CBC) prior to each dose (monitor for myelosuppression)
- Hepatic function panel
- Renal function panel
- Gastrointestinal signs (vomiting, diarrhea, anorexia)
- Ophthalmic exam (monitor for retinal haemorrhage)
Pharmacokinetics
Half-life
Absorption
Administered intravenously.
Distribution
Volume of distribution (steady-state) in dogs is around 1 L/kg. In humans, protein binding is negligible.
Metabolism
Metabolized intracellularly to active diphosphate and triphosphate forms. The primary inactive metabolite is uracil.
Elimination
Exhibits first-order elimination. Approximately 80% of the drug is excreted in the urine within 24 hours of dosing, primarily as the uracil metabolite.
Overdose
There is no known antidote to gemcitabine in an overdose situation. Severe myelosuppression should be expected. Treatment is supportive.
Available products
Formulations
- Lyophilized powder for injection
- Injectable: Lyophilized powder for reconstitution (200 mg in 10 ml vials)
- Injectable: Lyophilized powder for reconstitution (1 g in 50 ml vials)
Human-labeled
- Gemcitabine HCl lyophilized Powder for Injection: 200 mg (in 10 mL single-use vials) and 1 g (in 50 mL single-use vials) (Gemzar)
- Gemzar 200 mg lyophilized powder for injection
- Gemzar 1 g lyophilized powder for injection
Regulatory status
Human authorized product used off-label under the cascade (POM).
Human authorized product used off-label under the cascade (POM).
No regulatory data for: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Store unreconstituted vials at controlled room temperature (20-25°C). Reconstitute with preservative-free 0.9% sodium chloride. Reconstituted solution is stable for 24 hours at room temperature, or 7 days when frozen at -20°C. Do not refrigerate as crystallization may occur. Maximum concentration should not exceed 40 mg/mL.
Client information
- Investigational Therapy: Understand that veterinary experience with gemcitabine is limited, and it must be considered an 'investigational' treatment.
- Safety Precautions: Gemcitabine is a hazardous chemotherapy drug. Drug residues can be detected in your pet's urine for up to 7 days after a dose.
- Always wear disposable gloves when cleaning up urine, feces, or vomit from treated pets.
- Monitoring: Your pet will need frequent blood tests to monitor white blood cell and platelet counts, as this drug can suppress the bone marrow. Watch for signs of lethargy, bruising, or gastrointestinal upset.
VetSheet drug reference is intended for licensed veterinary professionals as a clinical decision-support aid, not a substitute for professional judgement or the manufacturer’s current label.