Generic Fluorouracil

Introduction

Fluorouracil is a topical antimetabolite chemotherapy agent supplied in a tube of either 1 % or 5 % strength. It belongs to the class of pyrimidine-analog drugs that interfere with DNA synthesis in rapidly dividing cells. Marketed under brand names such as Efudex and Adrucil, the generic version is widely used for dermatologic precancerous lesions. The medication is indicated for several FDA-approved skin conditions and is also prescribed off-label for a variety of other dermatologic disorders.

What is Fluorouracil?

Fluorouracil (5-fluorouracil, 5-FU) is a synthetic fluorinated pyrimidine that mimics the natural nucleotide uracil. First synthesized in the s and introduced for cancer therapy in the early s, it quickly became a cornerstone of chemotherapy. In its topical formulation, the drug is packaged in a tube as a cream or ointment designed for direct application to the skin. Fluorouracil is the generic version of well-known medications, containing the active compound 5-fluorouracil. Our online pharmacy provides this generic alternative as a cost-effective treatment option.

How Fluorouracil Works

Fluorouracil exerts its cytotoxic effect through two inter-related mechanisms:

• Thymidylate synthase inhibition - The drug is metabolised intracellularly to 5-fluoro-2′-deoxyuridine-5′-monophosphate, which forms a stable ternary complex with thymidylate synthase and folate co-factor. This blocks the conversion of deoxyuridine monophosphate (dUMP) to deoxythymidine monophosphate (dTMP), halting DNA synthesis in proliferating cells.
• RNA incorporation - Another metabolite, 5-fluorouridine triphosphate, is incorporated into RNA in place of uridine, disrupting normal RNA processing and protein synthesis.

When applied to the skin, the drug predominantly affects rapidly dividing keratinocytes in actinic or neoplastic lesions, leading to cell death, ulceration, and eventual clearance of the abnormal tissue. Systemic absorption from topical use is minimal, but the mechanism remains identical to that of intravenous 5-FU.

Conditions Treated with Fluorouracil

Approved (on-label) indications for the topical 1 % or 5 % formulations

• Actinic keratosis (AK) - Precancerous lesions caused by chronic UV exposure. Fluorouracil induces selective necrosis of dysplastic keratinocytes, resulting in lesion resolution.
• Superficial basal cell carcinoma (sBCC) - Thin, non-invasive basal cell cancers confined to the epidermis and upper dermis. The drug eradicates tumor cells while preserving surrounding normal tissue.
• Field-cancerisation (multiple AKs in a contiguous area) - The cream can be applied to a broader area to treat numerous subclinical lesions simultaneously.

These indications are supported by randomized controlled trials demonstrating superior clearance rates compared with placebo or simple emollients.

Off-Label and Investigational Uses of Fluorouracil

• Bowen disease (in situ squamous cell carcinoma) - Small case series have shown complete histologic clearance after a 6-week course of 5 % cream.
• Genital or common warts (verrucae vulgaris) - Topical 5 % fluorouracil combined with keratolytic agents has produced partial to complete regression in pilot studies.
• Keloid and hypertrophic scar management - Intralesional or topical fluorouracil is sometimes employed to soften scar tissue and reduce thickness, based on limited observational data.
• Melanoma in situ - Some dermatologists use fluorouracil after excisional biopsy to treat residual atypical melanocytes, though robust evidence is lacking.
• Radiation-induced dermatitis - Small trials suggest that brief courses of low-strength fluorouracil may accelerate re-epithelialisation of severe radiation burns.

These applications have not received regulatory approval. Their effectiveness and safety remain under investigation, and any off-label use should be undertaken only under the direct supervision of a qualified healthcare provider.

Is Fluorouracil the Right Medication for You?

Fluorouracil is most appropriate for adults who have a confirmed diagnosis of actinic keratosis, superficial basal cell carcinoma, or a field of multiple AKs where a physician has elected topical chemotherapy over surgical excision. Patients with a known hypersensitivity to fluorouracil or any component of the cream, pregnant or breastfeeding women, and individuals with severe immunosuppression (e.g., AIDS, organ-transplant recipients) are generally contraindicated.

People with a hereditary deficiency of dihydropyrimidine dehydrogenase (DPD), the enzyme responsible for fluorouracil catabolism, are at risk for severe systemic toxicity even from limited skin absorption and should avoid the drug.

Risks, Side Effects, and Interactions

Common

• Erythema and burning sensation - Typically appears within 24-48 hours of the first application.
• Crusting and ulceration - Progresses as dysplastic cells are destroyed; expected in target lesions.
• Pain or tenderness - May be managed with cool compresses or topical analgesics.

Rare

• Hyperpigmentation - Post-inflammatory darkening of treated skin lasting weeks to months.
• Allergic contact dermatitis - Characterised by severe itching, swelling, and vesiculation; requires discontinuation.
• Scarring - Excessive tissue loss may lead to permanent atrophic scars, especially if lesions are overlying bony prominences.

Serious

• Severe ulceration with secondary infection - May necessitate systemic antibiotics and wound care.
• Systemic toxicity - Rare but possible if large surface areas are treated; signs include bone-marrow suppression, gastrointestinal upset, or neurotoxicity. Immediate medical evaluation is essential.

Interactions

• Concurrent topical irritants (e.g., imiquimod, retinoids) can intensify local inflammation; co-administration should be timed or avoided.
• Systemic chemotherapy agents (e.g., capecitabine) may potentiate fluorouracil-related toxicity; clinicians should coordinate dosing.
• Alcohol and sun exposure do not directly interact with the cream, but UV light can worsen skin irritation; patients should limit sun exposure and use broad-spectrum sunscreen after treatment.

Use: Dosing, Missed Dose, Overdose

• Standard dosing - Apply a thin, even layer to the entire lesion or field once daily at night, after cleansing and drying the skin. For 1 % cream, treatment usually lasts 2-4 weeks; for 5 % cream, 2-6 weeks is typical, depending on the indication and physician guidance.
• Missed dose - If a dose is forgotten, apply it as soon as remembered unless the next scheduled dose is within a few hours; in that case, skip the missed application to avoid excess irritation.
• Overdose - Applying the cream to an area larger than prescribed or using a higher concentration than recommended can increase systemic absorption. Symptoms of overdose (e.g., nausea, severe fatigue, hematologic changes) require urgent medical assessment.

Practical precautions

• Avoid covering treated skin with occlusive dressings unless directed by a clinician.
• Wash hands thoroughly after each application to prevent inadvertent contact with eyes or mucous membranes.
• Use sunscreen (SPF 30 or higher) on untreated skin after the treatment period; do not apply sunscreen over the medication while it is active.
• Refrain from operating heavy machinery or performing tasks that could be impaired by pain or discomfort until the skin stabilises.

FAQ

• What temperature should Fluorouracil cream be stored at? The cream should be kept at room temperature, generally between 20 °C and 25 °C (68 °F-77 °F). Extreme heat or cold can alter its consistency and potency.

• Can I travel internationally with Fluorouracil in my luggage? Yes, the product may be carried in hand luggage, but it should be sealed in its original packaging with the label visible. Some countries restrict import of chemotherapy agents, so checking local customs regulations before travel is advisable.

• How long does an opened tube of Fluorouracil remain effective? Once opened, the cream is stable for up to 12 weeks if stored correctly and the cap is tightly closed. Discard any product that changes colour, develops an unusual odor, or shows separation.

• What is the difference between the 1 % and 5 % strengths? The 1 % formulation is typically prescribed for diffuse actinic keratosis across a broad field, requiring a longer treatment duration with milder irritation. The 5 % strength is used for isolated lesions such as superficial basal cell carcinoma, delivering a more rapid but potentially more intense inflammatory response.

• Is it safe to use sunscreen while I’m applying Fluorouracil? Sunscreen should not be applied to the treated area during the active course, as it can trap the medication and increase irritation. After treatment completion and once the skin has healed, regular sunscreen use is recommended to prevent new sun-induced lesions.

• Can I apply Fluorouracil on tattoos or pigmented lesions? Application over tattooed skin may cause unexpected pigment changes or scarring. It is best to avoid treating pigmented lesions unless specifically instructed by a dermatologist.

• Will Fluorouracil affect routine blood tests? Topical use usually results in negligible systemic absorption, so routine laboratory values are not expected to change. However, extensive application over large body surface areas could lead to mild marrow suppression detectable on blood counts.

• Does Fluorouracil cause hair loss? Systemic chemotherapy with 5-FU can cause alopecia, but the topical formulation applied to the skin rarely impacts scalp hair because of limited systemic exposure.

• Is the medication safe for people with diabetes? Diabetes does not contraindicate Fluorouracil use. Nevertheless, individuals with diabetic peripheral neuropathy should monitor treated areas carefully, as reduced sensation may mask early signs of severe irritation or ulceration.

• Can I use other over-the-counter skin products while on Fluorouracil? Mild, fragrance-free moisturisers may be applied to untreated surrounding skin after the medication has dried. Potent keratolytics, acids, or retinoids should be avoided during treatment to prevent excessive irritation.

Glossary

Thymidylate synthase

An enzyme essential for converting dUMP to dTMP, a building block of DNA. Fluorouracil’s active metabolites bind this enzyme, halting DNA synthesis in rapidly dividing cells.

Antimetabolite

A class of drugs that resemble natural metabolites and interfere with essential biochemical pathways, ultimately inhibiting cell growth and replication.

Hyperpigmentation

Darkening of the skin that occurs after inflammation or injury, often as a post-inflammatory response to topical chemotherapy.

Dihydropyrimidine dehydrogenase (DPD) deficiency

A hereditary condition in which the body cannot adequately break down fluorouracil, increasing the risk of severe systemic toxicity even from low-dose exposure.

Buying Fluorouracil from Our Online Pharmacy

Fluorouracil is available for purchase through our online pharmacy. We source the medication directly from licensed, international manufacturers that meet strict quality-assurance standards, ensuring the product you receive matches the potency and purity of the original formulation.

• Cost-effectiveness - Prices are set close to wholesale rates, offering a significant saving compared with many domestic retail pharmacies.
• Verified quality - Every batch is accompanied by a certificate of analysis and undergoes independent testing before shipment.
• Secure and discreet delivery - Orders are packaged in unmarked parcels and dispatched via reliable carriers, with options ranging from express (7 days) to standard airmail (approximately 3 weeks).
• Privacy-focused service - As a pharmacy-broker, we work with overseas licensed pharmacies, allowing us to provide access to medications that may be difficult to obtain locally, while maintaining strict confidentiality of your personal information.

Our goal is to make a trusted, affordable supply of Fluorouracil reachable for patients who encounter barriers through conventional pharmacy channels.

Disclaimer

The information presented about Fluorouracil is intended for general educational purposes and does not substitute for professional medical advice. Treatment decisions, including any off-label applications, should be made only under the supervision of a qualified healthcare professional. Readers are presumed to be competent adults capable of making informed health choices. Our online pharmacy supplies Fluorouracil for individuals who may have limited access through traditional pharmacies or who seek a cost-effective generic alternative. Always consult a clinician before initiating, modifying, or discontinuing any medication.