Capecitabine Medications

Capecitabine is an oral fluoropyrimidine antimetabolite that converts inside the body to 5-fluorouracil (5-FU), a chemotherapy agent that interferes with DNA synthesis in rapidly dividing cells. It is widely prescribed for several solid tumours, including metastatic colorectal, breast, and gastric cancers, and is available in both brand-name (Xeloda) and generic formulations. By delivering 5-FU preferentially to tumour tissue, capecitabine aims to maximize anticancer activity while reducing systemic toxicity. Beyond its approved uses, clinicians sometimes employ capecitabine off-label for certain gastrointestinal malignancies when evidence suggests comparable efficacy. Understanding its molecular action, dosing patterns, and safety profile helps patients and caregivers navigate treatment decisions and anticipate the therapeutic timeline.

What is Capecitabine?

Capecitabine belongs to the class of antimetabolite chemotherapeutic agents known as fluoropyrimidines. The Health Sciences Authority of Singapore granted approval in 2002 for its use in metastatic colorectal cancer, and later extensions covered adjuvant colon cancer after surgical resection, metastatic breast cancer (in combination with docetaxel), and metastatic gastric cancer. The U.S. Food and Drug Administration and the European Medicines Agency echo these approvals, citing robust phase-III trial data that demonstrated improved progression-free survival compared with some standard regimens.

At the molecular level, capecitabine undergoes a three-step enzymatic conversion: first, hepatic carboxylesterases cleave the carbamate group; second, cytidine deaminase removes the amino group; finally, tumour-enriched thymidine phosphorylase transforms the intermediate into 5-FU. Once formed, 5-FU binds and inhibits thymidylate synthase, depleting the nucleotide pool required for DNA replication. This selective activation mechanism is why capecitabine is often preferred for patients who cannot tolerate continuous intravenous 5-FU.

Both branded (Xeloda) and generic versions are stocked in our online pharmacy, offering a convenient way to obtain the medication without compromising on quality.

How Capecitabine Works

Mechanism of Action

Capecitabine is a prodrug that exploits tumour-specific enzymatic activity. After oral absorption, it travels through the bloodstream to the liver, where carboxylesterase initiates conversion to 5′-deoxy-5-fluorocytidine (5′-dFCR). Cytidine deaminase, present in both liver and tumour tissue, produces 5′-deoxy-5-fluorouridine (5′-dFUR). The final step-cleavage by thymidine phosphorylase, an enzyme overexpressed in many cancers-yields active 5-fluorouracil. 5-FU then incorporates into RNA and, more importantly, forms a stable ternary complex with thymidylate synthase and reduced folate, halting the synthesis of thymidine monophosphate, a DNA precursor.

Therapeutic Effects

By starving tumour cells of thymidine, capecitabine arrests the S-phase of the cell cycle, leading to apoptosis. The preferential activation within malignancies spares most normal tissues, which explains the comparatively lower rates of systemic toxicity versus continuous intravenous 5-FU. Clinically, this translates into tumour shrinkage, delayed disease progression, and improved overall survival in several randomized studies.

Onset and Duration

Plasma concentrations of capecitabine peak within 1-2 hours after ingestion, but measurable 5-FU levels appear after 2-3 hours, coinciding with the enzymatic conversion cascade. Therapeutic effects, such as tumour marker reduction or imaging-confirmed response, are typically observed after 2-3 cycles (each cycle lasts 21 days). The drug’s half-life is roughly 45 minutes for capecitabine and 10-20 minutes for 5-FU, yet the cytotoxic impact persists until tumour DNA synthesis resumes, usually within 48 hours after the last dose.

Approved Uses and Applications

Approved Indications

• Metastatic colorectal cancer - First-line therapy, either alone or combined with oxaliplatin-based regimens (HSA, 2002).
• Adjuvant colon cancer - Post-surgical treatment to reduce recurrence risk (EMA, 2005).
• Metastatic breast cancer - In combination with docetaxel for patients who have received prior anthracycline therapy (FDA, 2006). -Metastatic gastric cancer - Often paired with cisplatin or oxaliplatin in patients unable to receive continuous 5-FU (EMA, 201).

These approvals stem from pivotal trials such as the X-ACT study (colon cancer) and the CAIRO series (colorectal), which demonstrated statistically significant improvements in disease-free survival and overall response rates.

Off-Label Uses

Capecitabine has been explored off-label for pancreatic adenocarcinoma, cholangiocarcinoma, and certain head-and-neck cancers, especially when combined with radiotherapy. Though not formally sanctioned by regulatory agencies, peer-reviewed case series and phase-II trials suggest modest activity; clinicians must weigh these data against established standards.

Clinical Efficacy

In the landmark X-ELOBA trial, capecitabine monotherapy achieved a 57 % response rate in metastatic colorectal patients, compared with 43 % for bolus 5-FU. A meta-analysis published in The Lancet Oncology reported a median progression-free survival of 8.1 months for capecitabine-based regimens versus 6.4 months for traditional 5-FU, reinforcing its therapeutic advantage in selected cohorts.

Buying Capecitabine from Our Online Pharmacy

Why Choose Our Service

Accessing capecitabine in Singapore can be challenging due to limited stock in some local outlets. Our online pharmacy bridges that gap, delivering the medication directly to your doorstep while preserving confidentiality. By leveraging a network of licensed international suppliers, we ensure each shipment meets stringent quality standards.

Brand Names and Generic Options

• Xeloda - The original brand, recognized for its consistent bioavailability.
• Capecitabine-Mylan - A reputable generic with comparable pharmacokinetic profile.
• Capecitabine-Sandoz - Another cost-effective alternative approved in multiple jurisdictions.

Our pharmacy service typically offers generics at 30-45 % lower price than the branded product, allowing patients to maintain treatment adherence without financial strain.

Quality & Safety

We partner with pharmacies that operate under certified Good Manufacturing Practice (GMP) conditions and are audited by the WHO pre-qualification programme. Each batch undergoes third-party testing for potency, purity, and absence of contaminants before dispatch.

Pricing & Access

Through our online service, a 500 mg tablet pack (30 tablets) averages SGD 150 per month for the generic, versus SGD 210 for the brand. Repeat customers benefit from a lifetime 10 % discount on all reorders, making long-term therapy more sustainable.

Discreet Delivery

Orders ship via express courier in approximately 7 days, with standard shipping taking up to three weeks. Packages are sealed in plain, non-descriptive boxes to protect privacy.

Dosing, Formulations & Administration

Available Formulations

Capecitabine is supplied as film-coated tablets in 150 mg, 500 mg, and 1 g strengths. No liquid or injectable forms exist, reflecting its design for oral administration.

Typical Dosing Ranges

For metastatic colorectal cancer, clinicians often start with 125 mg/m² taken twice daily for two consecutive weeks, followed by a seven-day rest period (the 14-days-on/7-days-off schedule). In breast cancer protocols, the dose may be reduced to 100 mg/m² under the same cycling scheme, especially when paired with docetaxel. Dosing is adjusted based on body surface area, renal function, and tolerability. Importantly, any dosage modification should be guided by a qualified prescriber.

Administration Guidelines

Capecitabine tablets should be swallowed whole with water, preferably after a light meal to lessen gastrointestinal irritation. Food does not markedly affect absorption, but taking the drug on an empty stomach can increase nausea. Patients are advised to maintain adequate hydration and report any severe hand-foot redness promptly. The treatment cycle repeats every three weeks unless toxicity necessitates a dose interruption.

The exact regimen must be individualized by a qualified healthcare professional.

Safety Profile & Considerations

Common Side Effects

• Hand-Foot Syndrome (Palmar-Plantar Erythrodysesthesia) - Reported in >30 % of patients; presents as redness, swelling, and pain on the palms and soles.
• Diarrhea - Occurs in roughly 20 % of users; can be severe and lead to dehydration if unmanaged.
• Nausea and Vomiting - Affects about 15 % of patients; anti-emetics are often co-prescribed.
• Mucositis - Inflammation of the oral mucosa, seen in 10-12 % of cases.
• Fatigue - Frequently reported, though usually mild to moderate.

Incidence figures are drawn from pivotal phase-III trials and the FDA prescribing information.

Serious Adverse Events

• Neutropenia - Absolute neutrophil count < 500 cells/µL in < 5 % of patients; increases infection risk.
• Cardiotoxicity - Rare cases of angina-like chest pain or myocardial infarction have been documented; immediate medical evaluation is warranted.
• Severe Hand-Foot Reaction - May lead to dose reduction or discontinuation if Grade 3-4 toxicity develops.

Contraindications

Capecitabine should not be used in individuals with known hypersensitivity to fluoropyrimidines, severe hepatic impairment (Child-Pugh C), or in patients with dihydropyrimidine dehydrogenase (DPD) deficiency, a genetic condition that hampers 5-FU metabolism.

Drug Interactions

• CYP450 Enzyme Inhibitors - While capecitabine itself is not a CYP substrate, concomitant use of strong inhibitors (e.g., ketoconazole) can alter the metabolism of supportive drugs.
• Anticoagulants - 5-FU can potentiate bleeding risk; close monitoring of INR/PT is advised when warfarin is co-administered.
• Other Antimetabolites - Combining with methotrexate or fluorouracil increases myelosuppression risk.
• Herbal Supplements - St. John’s Wort, a CYP3A4 inducer, may reduce efficacy of adjunctive anti-emetics.

Special Populations

• Pregnancy & Breastfeeding - Contraindicated; capecitabine is teratogenic and excreted in breast milk.
• Elderly - Age-related renal decline may necessitate dose reduction; monitoring of creatinine clearance is essential.
• Renal Impairment - Patients with CrCl < 30 mL/min require a 25 % dose reduction.
• Hepatic Dysfunction - Moderate liver disease warrants a 25 % dose cut-back; severe disease is a contraindication.

Professional oversight is vital to tailor therapy to each patient’s clinical profile.

Frequently Asked Questions

• What is the difference between capecitabine and intravenous 5-fluorouracil? Capecitabine is an oral prodrug that becomes 5-5-FU mainly within tumour cells, while intravenous 5-FU delivers the active drug systemically, often requiring continuous infusion. The oral route improves convenience but still carries similar toxicity profiles.

• How long does capecitabine take to produce noticeable tumour shrinkage? Radiographic responses are usually detected after 2-3 treatment cycles (6-9 weeks). Symptomatic improvement, such as pain relief, may appear earlier, often within the first two weeks as the drug reduces tumour-derived inflammation.

• What should I do if I develop hand-foot syndrome? Reduce friction and heat exposure to the affected areas, use emollient creams, and keep nails trimmed. Promptly inform your clinician; dose interruption or reduction may be necessary to prevent progression to severe grades.

• Is it safe to take capecitabine with alcohol? Moderate alcohol consumption does not directly interact with capecitabine, but excessive intake can worsen liver function and increase the risk of gastrointestinal side effects. Discuss your drinking habits with your healthcare provider.

• Does food affect capecitabine absorption? Food modestly slows absorption but does not change overall exposure. Taking the medication with a light meal helps mitigate nausea without compromising efficacy.

• Can I receive a COVID-19 vaccine while on capecitabine? Current guidelines suggest that inactivated or mRNA vaccines are safe for patients undergoing chemotherapy. Schedule vaccination during a low-toxicity phase of your cycle, ideally before the start of a new treatment week.

• What are the key signs of severe toxicity that require immediate medical attention? Sudden chest pain, high fever, persistent vomiting, grade 3-4 diarrhea, or a rapid drop in white-blood-cell count should prompt urgent evaluation. Contact your oncology team or visit the nearest emergency department.

• How does renal function influence capecitabine dosing? Impaired clearance leads to higher systemic exposure of the active metabolite. Patients with creatinine clearance below 30 mL/min typically receive a 25 % dose reduction, and dose adjustments are guided by laboratory monitoring.

• Are there any dietary restrictions while on capecitabine? No specific foods must be avoided, but a balanced diet rich in protein supports tissue repair. Avoid grapefruit unless your physician advises otherwise, as it can impact concurrent medication metabolism.

• What information should I provide my doctor when discussing capecitabine?

  • Complete list of current medications, including over-the-counter drugs and supplements.
  • History of liver or kidney disease, and any known enzyme deficiencies (e.g., DPD).
  • Prior chemotherapy tolerance and any previous severe side effects.
  • Specific treatment goals (curative vs. palliative) and personal preferences regarding administration schedule.

Disclaimer

The information provided about capecitabine is for general knowledge only. It does not replace professional medical consultation or the official prescribing information for medications containing this ingredient. All treatment decisions, including dosing, formulation selection, and monitoring, should be made under the supervision of a qualified healthcare provider who can assess individual medical history, current medications, and specific health needs. We assume all readers are responsible adults capable of making informed decisions about their health. Our online pharmacy offers access to medications containing capecitabine for individuals who may have limited availability through traditional pharmacies, prescription-based insurance schemes, or who are seeking affordable generic alternatives. Always consult your doctor before starting, changing, or discontinuing any medication containing capecitabine.

External Resources about Capecitabine

• Capecitabine Overview - Active Ingredient - RxReasoner
• Capecitabine - MIMS
• Capecitabine: Uses, Interactions, Mechanism of Action | DrugBank Online
• Capecitabine – Arasto
• Capecitabine medac, INN-capecitabine - European Medicines …