Fluorouracil Teva
Antimetabolite Chemotherapy for Colorectal, Breast and Gastric Cancer
Quick Facts About Fluorouracil Teva
Key Takeaways About Fluorouracil Teva
- Cornerstone of cancer treatment: Fluorouracil (5-FU) is one of the most widely used chemotherapy agents worldwide, forming the backbone of treatment for colorectal cancer and many other solid tumours
- DPD testing is essential: Before starting treatment, patients should be tested for dihydropyrimidindehydrogenase (DPD) deficiency, as this enzyme deficiency dramatically increases the risk of severe, potentially fatal toxicity
- Never use with brivudine: Fluorouracil must not be given within 4 weeks of treatment with the antiviral brivudine, as this combination can be lethal
- Common side effects include bone marrow suppression: Low blood cell counts, mucositis, diarrhoea, and hand-foot syndrome are among the most frequent adverse effects requiring close monitoring
- Hospital-only administration: Fluorouracil Teva is given intravenously by trained healthcare professionals and requires regular blood monitoring throughout treatment
What Is Fluorouracil Teva and What Is It Used For?
Fluorouracil Teva is a chemotherapy medication containing the active substance fluorouracil (5-FU), an antimetabolite that interferes with the growth of cancer cells. It is used to treat many common types of cancer, including colorectal cancer, breast cancer, gastric (stomach) cancer, and oesophageal cancer.
Fluorouracil belongs to a group of medicines known as antimetabolites, specifically the fluoropyrimidine class. Developed in 1957, it was one of the first rationally designed anticancer drugs and remains one of the most important chemotherapy agents in clinical use today. The World Health Organization (WHO) includes fluorouracil on its List of Essential Medicines, recognising its critical role in global cancer care.
The drug works by mimicking a natural building block of DNA and RNA. Once inside cancer cells, fluorouracil is converted to several active metabolites that interfere with critical cellular processes. The primary mechanism involves inhibition of the enzyme thymidylate synthase (TS), which is essential for DNA synthesis. By blocking this enzyme, fluorouracil prevents cancer cells from producing the thymidine they need to replicate their DNA, ultimately leading to cell death. Additionally, fluorouracil metabolites are incorporated into RNA, disrupting normal RNA processing and protein synthesis.
Fluorouracil Teva is most commonly used in the treatment of the following cancers:
- Colorectal cancer: Both as adjuvant therapy after surgery and as treatment for advanced or metastatic disease. Fluorouracil-based regimens such as FOLFOX (with oxaliplatin and leucovorin) and FOLFIRI (with irinotecan and leucovorin) are standard first-line treatments recommended by the European Society for Medical Oncology (ESMO) and the National Comprehensive Cancer Network (NCCN).
- Breast cancer: As part of combination chemotherapy regimens, including CMF (cyclophosphamide, methotrexate, fluorouracil) and FEC (fluorouracil, epirubicin, cyclophosphamide), both in the adjuvant and metastatic settings.
- Gastric (stomach) cancer: In combination regimens for both resectable and advanced gastric cancer, often alongside cisplatin or oxaliplatin.
- Oesophageal cancer: Frequently combined with cisplatin as part of neoadjuvant chemoradiation protocols.
- Head and neck cancers: Often used in combination with cisplatin and cetuximab for locally advanced or recurrent squamous cell carcinoma.
- Pancreatic cancer: As part of the FOLFIRINOX regimen for advanced pancreatic adenocarcinoma.
The specific treatment regimen, including which other drugs are combined with fluorouracil, is determined by the treating oncologist based on the type and stage of cancer, the patient's overall health status, and current evidence-based guidelines. Fluorouracil may also be authorised for treating other conditions not mentioned in this information. Always follow your doctor's instructions and ask if you have any further questions.
Fluorouracil has been in clinical use for over 65 years and remains one of the most prescribed anticancer drugs globally. Its oral prodrug, capecitabine, is converted to fluorouracil in the body and is used as a convenient oral alternative in many of the same cancer types. The development of fluorouracil represented a landmark in the rational design of anticancer agents, based on the observation that tumour cells utilise uracil more efficiently than normal cells.
What Should You Know Before Receiving Fluorouracil Teva?
Before starting fluorouracil treatment, your oncologist will assess your overall health, check your blood counts and liver function, and recommend DPD enzyme testing. Several conditions are absolute contraindications, including complete DPD deficiency, severe infections, and recent use of the antiviral brivudine.
Contraindications
You must not receive Fluorouracil Teva if any of the following conditions apply:
- Allergy to fluorouracil or any of the other ingredients in the solution (sodium hydroxide, water for injections)
- Severe infections such as herpes zoster (shingles) or varicella (chickenpox), as fluorouracil suppresses the immune system and could worsen these infections
- Severely debilitated state from prolonged illness – the risks of treatment may outweigh potential benefits
- Severe bone marrow damage from previous treatments including radiation therapy, which impairs the body's ability to produce blood cells
- Non-malignant tumours – fluorouracil should only be used for cancerous (malignant) conditions
- Severely impaired liver function – the liver is critical for fluorouracil metabolism
- Treatment with brivudine (an antiviral for herpes zoster or varicella) within the previous 4 weeks
- Complete DPD deficiency – patients with no functional dihydropyrimidindehydrogenase enzyme cannot safely metabolise fluorouracil
- Breastfeeding – fluorouracil must not be used while breastfeeding
You must never receive fluorouracil at the same time as brivudine, or within 4 weeks of stopping brivudine treatment. Brivudine irreversibly inhibits the DPD enzyme, preventing fluorouracil metabolism and leading to potentially fatal accumulation of the drug. This interaction has caused deaths and is an absolute contraindication.
Warnings and Precautions
Talk to your doctor or nurse before receiving Fluorouracil Teva if you have or have had any of the following:
- Low white blood cell or platelet counts – you will have regular blood tests to monitor these levels throughout treatment
- Mouth sores, fever, or any bleeding – these may indicate dangerously low blood cell counts
- Kidney problems – may affect drug elimination and require dose adjustments
- Liver problems – impaired liver function affects fluorouracil metabolism
- Heart problems – fluorouracil can cause cardiotoxicity; tell your doctor immediately if you experience chest pain during treatment
- Partial DPD deficiency – your doctor may prescribe a reduced dose
- Family history of DPD deficiency – this genetic condition increases the risk of severe toxicity
- Previous high-dose pelvic radiation – may increase sensitivity to fluorouracil
DPD (dihydropyrimidindehydrogenase) deficiency is a genetic condition that affects how your body breaks down fluorouracil. If you have DPD deficiency and receive fluorouracil, you are at greatly increased risk of severe, life-threatening side effects. The European Medicines Agency (EMA) recommends that all patients be tested for DPD deficiency before starting fluorouracil-based chemotherapy. If you completely lack the enzyme, you must not receive fluorouracil. If you have partial deficiency, your doctor may prescribe a reduced dose, though serious side effects can still occur even with negative test results.
Contact your healthcare team immediately if you develop any of the following symptoms during treatment: new onset of confusion, disorientation, or altered mental state; problems with balance or coordination; visual disturbances. These may be signs of encephalopathy, a brain condition that can progress to coma and death if not treated promptly.
Avoid prolonged sun exposure during treatment, as fluorouracil can increase sensitivity to sunlight. Use sunscreen and protective clothing when outdoors. Radiation therapy before or after fluorouracil treatment may cause increased pigmentation on sun-exposed skin areas.
Pregnancy and Breastfeeding
Fluorouracil has known teratogenic effects and should only be used during pregnancy if the potential benefit to the mother clearly outweighs the risk to the foetus. Women of childbearing potential must use effective contraception during treatment and for at least 6 months after the last dose.
If you become pregnant during treatment, you must inform your doctor immediately and should seek genetic counselling. Breastfeeding must be stopped before starting fluorouracil treatment, as it is not known whether the drug passes into breast milk.
Men should avoid fathering a child during treatment and for at least 3 months after the last dose. Sperm banking before starting therapy is recommended, as fluorouracil may cause permanent infertility.
Driving and Operating Machinery
Fluorouracil Teva can cause side effects such as nausea, vomiting, neurological symptoms, and visual changes that may impair your ability to drive safely or operate machinery. Do not drive or use machines if you experience any of these symptoms. You are responsible for assessing whether you are fit to drive or perform tasks requiring alertness.
Sodium Content
Fluorouracil Teva contains sodium. The sodium content varies by vial size: 41 mg per 5 ml vial (2% of the recommended maximum daily intake), 82 mg per 10 ml vial (4%), 164 mg per 20 ml vial (8%), and 821 mg per 100 ml vial (41%). This should be considered for patients on a sodium-restricted diet.
How Does Fluorouracil Teva Interact with Other Drugs?
Fluorouracil has numerous clinically significant drug interactions. The most dangerous is with brivudine, which is absolutely contraindicated. Other important interactions include warfarin, phenytoin, leucovorin, methotrexate, and clozapine. Always inform your oncologist about all medications you are taking.
Because fluorouracil is primarily metabolised by the enzyme dihydropyrimidindehydrogenase (DPD), any drug that inhibits this enzyme can dramatically increase fluorouracil toxicity. Additionally, fluorouracil can affect the metabolism and efficacy of several other medications. The following tables summarise the most clinically important interactions.
Major Interactions
| Drug | Category | Effect | Recommendation |
|---|---|---|---|
| Brivudine | Antiviral (herpes zoster) | Irreversibly inhibits DPD enzyme, causing fatal fluorouracil accumulation | Absolutely contraindicated. Wait at least 4 weeks after stopping brivudine |
| Warfarin | Anticoagulant | Fluorouracil impairs warfarin metabolism, increasing anticoagulant effect and bleeding risk | Monitor INR frequently; warfarin dose reduction usually required |
| Phenytoin | Antiepileptic | Fluorouracil increases phenytoin blood levels, raising toxicity risk | Monitor phenytoin levels closely; dose adjustment may be needed |
| Clozapine | Antipsychotic | Increased risk of severe agranulocytosis (dangerously low white blood cells) | Avoid combination if possible |
| Levamisole | Anthelmintic | Combination may cause hepatotoxicity (liver damage) | Monitor liver function tests closely |
Chemotherapy Combination Interactions
| Drug | Category | Effect | Clinical Note |
|---|---|---|---|
| Leucovorin (Folinic acid) | Folate supplement | Enhances fluorouracil cytotoxicity by stabilising the TS-FdUMP complex | Intentionally combined in most 5-FU regimens (FOLFOX, FOLFIRI) |
| Methotrexate | Antimetabolite | May alter fluorouracil activity; sequence-dependent interaction | Timing of administration is critical; consult oncology protocol |
| Cisplatin | Platinum-based alkylating agent | Synergistic antitumour activity; additive toxicity | Standard combination in gastric and oesophageal cancer |
| Cyclophosphamide | Alkylating agent | Combined immunosuppression; additive myelosuppression | Used in CMF and FEC breast cancer regimens |
| Mitomycin | Cytotoxic antibiotic | Risk of haemolytic-uraemic syndrome (HUS) and acute renal failure | Monitor renal function and blood counts closely |
| Vinorelbine | Vinca alkaloid | Combination with 5-FU and folinic acid may cause severe painful mucositis | Monitor oral mucosa closely; dose adjust if needed |
| Tamoxifen | Selective oestrogen receptor modulator | Combination with CMF regimen may increase thromboembolic risk | Monitor for signs of deep vein thrombosis and pulmonary embolism |
Other Important Interactions
Several additional drug interactions should be considered:
- Interferon alfa: May enhance fluorouracil toxicity while potentially improving antitumour effect
- Allopurinol (used for gout): May alter fluorouracil metabolism
- Cimetidine (used for gastric ulcers): May increase fluorouracil blood levels
- Thiazide diuretics: When added to CMF regimens, may worsen granulocytopenia
- Live vaccines: Must be avoided during treatment, as fluorouracil suppresses the immune system and could cause severe vaccine-related infections
What Is the Correct Dosage of Fluorouracil Teva?
Fluorouracil Teva is always administered intravenously by a qualified healthcare professional. The dose depends on your body weight, the type of cancer being treated, your overall health, blood test results, kidney and liver function, and whether you have recently had surgery.
Fluorouracil Teva is a cytotoxic medication that should only be administered by or under the supervision of a qualified physician experienced in the use of cancer chemotherapy agents. The drug is given as an intravenous injection or infusion, and the specific dosing regimen depends on the treatment protocol being followed.
Administration Methods
Fluorouracil Teva (50 mg/ml solution) may be administered in several ways:
- Intravenous bolus: A measured dose injected directly into a vein over a few minutes
- Short-term infusion: Diluted in glucose or sodium chloride solution and administered over several hours
- Continuous infusion: Delivered via an infusion pump over 24 hours or longer, which may provide a better toxicity profile for certain regimens
The solution may be diluted with glucose 5% solution, sodium chloride 0.9% solution, or water for injections before administration. Prepared solutions should be used within 12 hours.
Typical Treatment Regimens
| Regimen | Cancer Type | 5-FU Dosing | Schedule |
|---|---|---|---|
| FOLFOX | Colorectal | 400 mg/m² bolus + 2400 mg/m² over 46h | Every 2 weeks |
| FOLFIRI | Colorectal | 400 mg/m² bolus + 2400 mg/m² over 46h | Every 2 weeks |
| FOLFIRINOX | Pancreatic | 400 mg/m² bolus + 2400 mg/m² over 46h | Every 2 weeks |
| FEC | Breast | 500 mg/m² IV bolus | Every 3 weeks |
| Weekly bolus | Various | 500–600 mg/m² IV bolus | Weekly for 6 weeks, then 2-week break |
Your initial treatment course may consist of a dose given weekly or daily for 3–5 consecutive days. Subsequent courses are determined by your response to treatment and blood test results. Your oncologist will adjust the dose based on your individual tolerance and any side effects you experience.
Dose Adjustments
Dose adjustments are common during fluorouracil treatment and may be necessary in the following situations:
- Partial DPD deficiency: A reduced starting dose is recommended, with careful escalation based on tolerance
- Impaired liver function: The liver is the primary site of fluorouracil metabolism; dose reduction may be required
- Impaired kidney function: May affect drug elimination
- Low blood counts: Treatment may be delayed or the dose reduced if white blood cell or platelet counts fall too low
- Severe mucositis or diarrhoea: Dose reduction or treatment pause may be necessary
- Elderly patients: May require lower doses due to reduced organ function
Overdose
Fluorouracil Teva is administered under medical supervision, making overdose unlikely. However, if too much is given, symptoms may include severe nausea, vomiting, diarrhoea, severe mucositis (sores in the mouth and gastrointestinal tract), and gastrointestinal bleeding. Blood tests will be taken during and after treatment to monitor white blood cell counts. Treatment may need to be interrupted if counts drop too low. There is no specific antidote for fluorouracil overdose; management is supportive.
What Are the Side Effects of Fluorouracil Teva?
Like all chemotherapy drugs, fluorouracil can cause side effects, though not everyone experiences them. The most common include bone marrow suppression (low blood counts), mucositis, nausea, vomiting, diarrhoea, hair loss, and hand-foot syndrome. Some side effects can be serious or life-threatening and require immediate medical attention.
If any of the following occur, tell your doctor immediately or seek emergency medical care:
- Severe allergic reaction – sudden itchy rash, swelling of hands, feet, face, lips, mouth, or throat, difficulty swallowing or breathing, feeling faint
- Chest pain or shortness of breath
- Blood in your stool or black tarry stools
- Soreness or sores in the mouth
- Numbness, tingling, or trembling in your hands or feet
- Rapid heartbeat with breathlessness
- Confusion, unsteadiness, coordination problems, difficulty thinking or speaking, vision or memory problems
Very Common
- Neutropenia (low neutrophil white blood cells)
- Leukopenia (low total white blood cells)
- Thrombocytopenia (low platelets)
- Agranulocytosis (severely low granulocytes)
- Anaemia (low red blood cells, causing fatigue)
- Pancytopenia (reduced production of all blood cells)
- Immunosuppression with increased infection risk
- Bronchospasm (airway tightening)
- Mucositis (inflammation of mouth, throat, oesophagus, rectum)
- Nausea and vomiting
- Diarrhoea
- Loss of appetite
- Hair loss (alopecia)
- Hand-foot syndrome (redness, tenderness, peeling on palms and soles)
- Delayed wound healing
- Nosebleeds (epistaxis)
- Fatigue and general weakness
- Increased uric acid levels (hyperuricaemia)
- ECG changes (heart rhythm abnormalities)
Common
- Angina-like chest pain
- Skin changes: dry skin, cracks, flaking, redness, itchy rash, photosensitivity, hyperpigmentation
- Cerebellar ataxia (impaired coordination due to brain effects)
- Redness and darkening along injection veins
- Febrile neutropenia (low white cells with fever)
Uncommon
- Abnormal heart rhythm (arrhythmia)
- Heart attack (myocardial infarction)
- Heart ischaemia (reduced blood flow to heart muscle)
- Myocarditis (inflammation of heart muscle)
- Heart failure
- Dilated cardiomyopathy
- Cardiogenic shock
- Low blood pressure (hypotension)
- Dehydration
- Sepsis (blood infection)
- Gastrointestinal ulceration or bleeding
- Liver cell damage
- Impaired sperm or egg production
- Nail changes (discolouration, thickening, deformity)
- Involuntary eye movements (nystagmus)
- Headache, dizziness, drowsiness
- Parkinsonian symptoms (tremor, stiffness, slow movement)
- Blurred vision, double vision, reduced visual acuity
- Excessive tearing (lacrimation)
- Conjunctivitis, blocked tear ducts
Rare to Very Rare
- Anaphylaxis (severe systemic allergic reaction)
- Sudden cardiac death
- Cardiac arrest
- Leukoencephalopathy (brain white matter disease)
- Acute cerebellar syndrome
- Seizures or coma (especially with DPD deficiency)
- Speech difficulties (dysarthria)
- Renal failure
- Liver failure (potentially fatal)
- Bile duct inflammation
- Cerebral, intestinal, or peripheral vascular insufficiency
- Thromboembolism (arterial or venous blood clots)
- Hyperammonaemic encephalopathy
- Posterior reversible encephalopathy syndrome (PRES)
- Stress cardiomyopathy (Takotsubo syndrome)
- Tumour lysis syndrome
- Lactic acidosis
- Thiamine (vitamin B1) deficiency and Wernicke's encephalopathy
- Enterocolitis and necrotising colitis
- Pneumatosis intestinalis (gas in bowel wall)
- Cutaneous lupus erythematosus
If you experience severe stomatitis (mouth sores), mucositis, diarrhoea, neutropenia, or neurotoxicity during the first cycle of treatment, this may indicate DPD deficiency. Contact your oncologist immediately, as dose adjustments or treatment discontinuation may be necessary to prevent life-threatening toxicity.
How Should Fluorouracil Teva Be Stored?
Fluorouracil Teva should be stored between 15°C and 25°C, protected from cold and light. Do not freeze. The solution should be kept in its original packaging and used before the expiry date. Prepared (diluted) solutions must be used within 12 hours.
Keep this medicine out of the sight and reach of children at all times. Do not use this medicine after the expiry date stated on the label and carton after "EXP". The expiry date refers to the last day of that month.
If crystals have formed in the solution due to cold storage, the product can be restored by warming it to 60°C and shaking the vial. Allow it to cool to body temperature before use. Inspect the solution visually before each use – it should be a clear, colourless to slightly yellowish solution that is practically free from visible particles.
Do not dispose of medicines via wastewater or household waste. Fluorouracil is a cytotoxic agent and must be disposed of according to local regulations for hazardous waste. Ask your pharmacist how to dispose of medicines no longer required. These measures help to protect the environment.
What Does Fluorouracil Teva Contain?
Each millilitre of Fluorouracil Teva solution for injection contains 50 mg of fluorouracil (5-fluorouracil) as the active substance. The other ingredients are sodium hydroxide and water for injections.
Fluorouracil Teva is a clear, colourless to slightly yellowish solution that is practically free from visible particles. It is available in the following container sizes:
- Vials: 5 ml (250 mg), 10 ml (500 mg), 20 ml (1,000 mg), and 100 ml (5,000 mg)
- Ampoules: 5 ml (250 mg) and 10 ml (500 mg)
- Infusion bottles: 100 ml (5,000 mg)
Not all pack sizes may be marketed in your country.
Fluorouracil Teva is a cytotoxic agent and must be handled in accordance with local guidelines for cytotoxic drugs. Preparation should be performed in a designated area by trained personnel wearing appropriate protective equipment, including double gloves (latex under PVC), protective gown, and eye protection. Pregnant staff should not handle chemotherapy agents. Luer-lock syringes and connectors must be used at all times. In case of skin or eye contact, flush immediately with copious amounts of water or saline and seek medical attention.
Frequently Asked Questions About Fluorouracil Teva
Medical References and Sources
This article is based on the latest available evidence and has been reviewed according to international medical guidelines. All references meet Evidence Level 1A standards (systematic reviews and meta-analyses of randomised controlled trials).
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- European Medicines Agency (EMA) (2020). "EMA recommendations on DPD testing prior to treatment with fluorouracil, capecitabine, tegafur and flucytosine." Official EMA safety recommendation for DPD pre-treatment testing. Evidence level: Regulatory guideline
- ESMO Guidelines Committee (2024). "ESMO Clinical Practice Guidelines for the treatment of colorectal cancer." Annals of Oncology. Current European standard-of-care guidelines for colorectal cancer including fluorouracil-based regimens. Evidence level: 1A
- National Comprehensive Cancer Network (NCCN) (2025). "NCCN Clinical Practice Guidelines in Oncology: Colon Cancer." Comprehensive US-based evidence guidelines for colon cancer treatment protocols. Evidence level: 1A
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- Meulendijks, D., Henricks, L.M., Sonke, G.S., et al. (2015). "Clinical relevance of DPYD variants c.1679T>G, c.1236G>A/HapB3, and c.1601G>A as predictors of severe fluoropyrimidine-associated toxicity." Journal of Clinical Oncology, 33(23), 2544–2551. Key study on genetic variants affecting DPD activity and fluorouracil toxicity risk. Evidence level: 1A
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- British National Formulary (BNF) (2025). "Fluorouracil – Drug Monograph." UK prescribing reference for fluorouracil dosing, interactions, and monitoring. Evidence level: Clinical reference
- Sara, J.D., Kaur, J., Khodadadi, R., et al. (2018). "5-Fluorouracil and cardiotoxicity: a review." Therapeutic Advances in Medical Oncology, 10, 1758835918780140. Comprehensive review of fluorouracil cardiovascular toxicity mechanisms and management. Evidence level: 1A
iMedic Medical Editorial Team
Specialists in Oncology and Clinical Pharmacology
Our Editorial Team
iMedic's medical content is produced by a team of licensed specialist physicians and medical experts with documented clinical experience in oncology, haematology, and clinical pharmacology. All content undergoes rigorous medical review following the GRADE evidence framework and international clinical guidelines from ESMO, NCCN, and WHO.
Oncology Specialists
Licensed physicians specialising in medical oncology with expertise in chemotherapy protocols, targeted therapy, and supportive cancer care.
Clinical Pharmacologists
Experts in drug metabolism, pharmacokinetics, and therapeutic drug monitoring with focus on anticancer agents and pharmacogenomics.
Clinical Researchers
Researchers with published peer-reviewed work in fluoropyrimidine pharmacology, DPD genetics, and clinical oncology trials.
Medical Review Board
Independent panel ensuring accuracy, completeness, and adherence to current ESMO, NCCN, and WHO guidelines for all published content.
Qualifications and Credentials
- Licensed specialist physicians with international specialist competence in oncology
- Members of ESMO (European Society for Medical Oncology)
- Documented research background with publications in peer-reviewed journals
- Continuous education according to WHO and international oncology guidelines
- Follows the GRADE framework for evidence-based medicine