Gemcitabine

Indications

Gemcitabine is used for: Lung cancer, pancreatic cancer, bladder cancer, breast cancer, ovarian carcinoma

Adult Dose

Pancreatic Cancer Indicated as first-line treatment for locally advanced (nonresectable Stage II or Stage III) or metastatic (Stage IV) adenocarcinoma of the pancreas 1000 mg/m² IV infusion over 30 minutes once/week x7 weeks; rest 1 week, THEN 1000 mg/m² IV on Days 1, 8, and 15 of each 28-day cycle Various regimens exist including monotherapy and in combination with other chemotherapy agents (eg, erlotinib, paclitaxel protein bound, capecitabine) Non-small Cell Lung Cancer 1000 mg/m² IV infusion over 30 minutes on days 1, 8, and 15 of each 28-day cycle, OR 1250 mg/m² IV infusion over 30 minutes on days 1 and 8 of each 21-day cycle Administer cisplatin 100 mg/m² IV after gemcitabine on day 1 Breast Cancer 1250 mg/m² IV infusion over 30 minutes on Days 1 and 8 of each 21-day cycle With paclitaxel 175 mg/m² on Day 1 as a 3 hr infusion before gemcitabine Ovarian Cancer 1000 mg/m² IV infusion over 30 minutes on Days 1 and 8 of each 21-day cycle With carboplatin AUC 4 on Day 1 after gemcitabine

Child Dose

Renal Dose

Administration

IV Preparation Reconstitute 200 mg vial with 5 mL 0.9% NaCl OR 1000 mg vial with 25 mL 0.9% NaCl IV Administration For IV infusion only Concentrated injection (10 mg/mL) must be diluted to 2 mg/mL prior to administration Infuse over 30 min Avoid rapid infusions

Contra Indications

Concurrent radical radiotherapy; pregnancy, lactation; hypersensitivity.

Precautions

Children, hepatic and renal impairment. May impair ability to drive or operate machinery. Discontinue on 1st sign of microangiopathic haemolytic anaemia. Prolonged infusion time (>60 minutes) and more frequent than wkly dosing may increase toxicity. Monitor CBC before every dose. Increased risk of haemolytic uraemic syndrome and/or thrombocytcpenic purpura which may lead to irreversible renal failure. Lactation: not known if excreted in breast milk; do not nurse

Pregnancy-Lactation

Interactions

May increase the anticoagulant effect of warfarin when used together.

Adverse Effects

Side effects of Gemcitabine : >10% N/V (69%),Anemia (65%),Elev LFTs (68%),Neutropenia (63%),Leukopenia (62%),Pain (48%),Proteinuria (45%),Fever (41%),Hematuria (35%),Rash (30%),Thrombocytopenia (24%),Dyspnea (23%),Constipation (23%),Diarrhea (19%),Flu-like syndrome (19%),Hemorrhage (17%),BUN increased (16%),Infection (16%),Alopecia (15%),Edema (13%),Elev bilirubin (13%) 1-10% Paresthesia (2-10%),Creatinine increased (2-8%),Inj site reactions (4%),Bronchospasm (2%) Potentially Fatal: Oesophagitis and pneumonitis when given with radical radiotherapy to the thorax.

Mechanism of Action

Gemcitabine is a synthetic pyrimidine nucleoside and cytarabine analogue which is metabolised intracellularly to active diphosphate and triphosphate nucleosides. It inhibits DNA synthesis by inhibiting DNA polymerase and ribonucleotide reductase. It also induces apoptosis and is primarily active against cells in the S-phase, but may also arrest cells at the G1-S border.