Pyrimidine antimetabolite chemotherapy Pregnancy: Gemcitabine should not be used during pregnancy unless clearly necessary — there are no adequate data in pregnant women and animal studies have shown reproductive toxicity. Women should be advised not to become pregnant during treatment. Breast-feeding must be discontinued during gemcitabine therapy. Men are advised not to father a child during and for up to 6 months after treatment, and to seek advice on sperm cryoconservation before treatment.

Gemcitabine (Specialist drug)

Brand names: Gemzar

Gemcitabine is an intravenous antimetabolite cytotoxic chemotherapy used by oncology specialists for cancers including pancreatic, non-small-cell lung, bladder, breast and ovarian cancer.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: 1,000 mg/m2 (1,250 mg/m2 in some combination regimens — see notes)

Route: Intravenous infusion over 30 minutes (intravenous use only)

Frequency: Bladder cancer, in combination with cisplatin: 1,000 mg/m2 on Days 1, 8 and 15 of each 28-day cycle, with cisplatin 70 mg/m2 on Day 1 following gemcitabine or on Day 2; the 4-week cycle is then repeated

OTHER INDICATIONS (all as a 30-minute intravenous infusion). PANCREATIC CANCER: 1,000 mg/m2 once weekly for up to 7 weeks followed by a week of rest; subsequent cycles are once weekly for 3 consecutive weeks out of every 4 weeks. NSCLC MONOTHERAPY: 1,000 mg/m2 once weekly for 3 weeks followed by a 1-week rest period, repeating the 4-week cycle. NSCLC COMBINATION: 1,250 mg/m2 on Days 1 and 8 of a 21-day cycle (cisplatin has been used at 75-100 mg/m2 once every 3 weeks). BREAST CANCER with paclitaxel: paclitaxel 175 mg/m2 on Day 1 over approximately 3 hours, followed by gemcitabine 1,250 mg/m2 on Days 1 and 8 of each 21-day cycle; absolute granulocyte count must be at least 1,500 x 10^6/L before starting the combination. OVARIAN CANCER with carboplatin: gemcitabine 1,000 mg/m2 on Days 1 and 8 of each 21-day cycle, with carboplatin on Day 1 to a target AUC of 4.0 mg/mL-min after gemcitabine. MONITORING AND DOSE MODIFICATION: for all indications, monitor platelet and granulocyte counts before each dose; an absolute granulocyte count of at least 1,500 x 10^6/L and platelets of 100,000 x 10^6/L are required before initiating a cycle. Within a cycle, dose is reduced or omitted per the SPC tables (for bladder, NSCLC and pancreatic cancer: 100% if granulocytes >1,000 and platelets >100,000; 75% if granulocytes 500-1,000 or platelets 50,000-100,000; omit if granulocytes <500 or platelets <50,000). In subsequent cycles for all indications the dose is reduced to 75% of the original cycle initiation dose after: granulocytes <500 x 10^6/L for more than 5 days, granulocytes <100 x 10^6/L for more than 3 days, febrile neutropenia, platelets <25,000 x 10^6/L, or a cycle delay of more than 1 week due to toxicity. For severe (Grade 3 or 4) non-haematological toxicity other than nausea and vomiting, withhold or decrease therapy at the treating physician's judgement. Prolongation of the infusion time and increased dosing frequency increase toxicity. If extravasation occurs the infusion must generally be stopped immediately and restarted in another vessel. PAEDIATRIC: safety and efficacy in children under 18 years have not been established and gemcitabine should not be used in children under 18 years because of safety and efficacy concerns. Should only be prescribed by a physician qualified in the use of anti-cancer chemotherapy.

Dose adjustments

Renal

Gemcitabine should be used with caution in patients with hepatic or renal insufficiency — there is insufficient information from clinical studies to allow clear dose recommendations for these populations. Laboratory evaluation of renal and hepatic function should be performed periodically.

Dose auto-extracted from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Hypersensitivity to the active substance or to any of the excipients
Breast-feeding

Side effects

Nausea with or without vomiting — reported in approximately 60% of patients, together with raised liver transaminases (AST/ALT) and alkaline phosphatase
Myelosuppression — leucopenia/neutropenia (Grade 3 = 19.3%, Grade 4 = 6%), thrombocytopenia and anaemia; reductions in thrombocyte, leucocyte and granulocyte counts are the dose-limiting reactions
Proteinuria and haematuria — reported in approximately 50% of patients
Dyspnoea — reported in 10-40% of patients (highest incidence in lung cancer patients); usually mild and passes rapidly
Allergic skin rash — approximately 25% of patients, associated with itching in 10%
Serious but less frequent: posterior reversible encephalopathy syndrome, capillary leak syndrome, haemolytic-uraemic syndrome/thrombotic microangiopathy, interstitial pneumonitis, serious hepatotoxicity including liver failure and death

Interactions

Concomitant radiotherapy (given together or 7 days or less apart) — toxicity has been reported (UK SPC section 4.4; the full section 4.5 was not retrieved in this bundle)
Yellow fever vaccine and other live attenuated vaccines — not recommended in patients treated with gemcitabine
Other chemotherapy — the risk of cumulative bone-marrow suppression must be considered when gemcitabine is given with other cytotoxic treatments

Clinical monograph

How it works

As a pyrimidine (nucleoside) analogue it is incorporated into DNA and inhibits ribonucleotide reductase, halting DNA synthesis and causing apoptosis of dividing cells.

Prescribing in practice

Myelosuppression is the main dose-limiting toxicity, so withhold or modify treatment according to blood counts and counsel on infection and bleeding risk.
Prolonging the infusion beyond the recommended duration increases toxicity, so administer over the specified short infusion time.
Rare but serious haemolytic uraemic syndrome, capillary leak syndrome and pulmonary toxicity can occur and require prompt recognition and discontinuation.

Monitoring

Monitor full blood count before each dose and check renal and hepatic function, with vigilance for pulmonary symptoms and signs of haemolytic uraemic syndrome.

Counselling the patient

Seek urgent help for fever, sore throat or unusual bruising or bleeding.
Mild flu-like symptoms are common shortly after an infusion.
Report new breathlessness, reduced urine output or marked swelling.

Evidence & guidelines

Gemcitabine is a long-established antimetabolite chemotherapy with efficacy across several solid tumours demonstrated in randomised trials and embedded in oncology treatment protocols.

Reference: SmPC; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways