Efurix

Quick links to important sections

Efurix

Method of action: Antitumour, Cytostatic

Treatment option: Cancer

Medically reviewed

Marina Burgos

Last updated on 22/12/2025

This page provides general, reference-level information compiled from official medical sources. It is not a substitute for professional medical advice, diagnosis, or treatment. For decisions about your health, please consult a qualified healthcare professional.

Overview of Efurix

What is Efurix?

Efurix is a topical dermatological treatment containing the active substance fluorouracil, which belongs to a group of medicines known as antimetabolites. It is specifically formulated as a cream to be applied directly to the skin for the treatment of certain pre-cancerous conditions and specific types of superficial skin changes.

Mechanism of Action

The active ingredient, fluorouracil, works by interfering with the production of DNA and RNA within cells. Because abnormal or rapidly dividing cells—such as those found in solar keratoses—take up the substance more readily than healthy skin cells, the treatment selectively targets these areas. This process leads to the destruction of the abnormal cells while allowing the surrounding healthy skin to eventually replace the treated area with new tissue.

Primary Indications

Efurix is primarily used for the management of the following skin conditions:

  • Actinic Keratosis (Solar Keratosis): These are rough, scaly patches on the skin caused by years of sun exposure. They are considered pre-cancerous because, if left untreated, they have the potential to develop into a type of skin cancer called squamous cell carcinoma.
  • Bowen's Disease: A very early form of skin cancer where the abnormal cells are confined to the outermost layer of the skin (the epidermis).

What to Expect During Treatment

When applied to the skin, Efurix typically causes a visible reaction. The treated areas usually become red, inflamed, and may develop crusting or peeling. This reaction is a sign that the medication is effectively targeting the abnormal cells. Once the treatment course is completed, the skin generally heals over several weeks, often resulting in a smoother appearance than before the treatment began.

What side effects are possible with Efurix?

Possible Side Effects and Safety Information

The safety profile of Efurix (Fluorouracil Topical) is primarily characterized by local application site reactions, which are a recognized outcome of the drug's intended action as a cytotoxic agent. Regulatory documents classify these effects, which include pain, irritation, burning, erythema (redness), oedema (swelling), crusting, erosion, and pruritus (itching), as Very Common (ge 1/10).

The local inflammatory reaction is expected to follow a predictable time course, generally reaching its maximum intensity during the second or third week of the prescribed regimen, as documented in official labeling.

Serious Risks and Safety Constraints

Serious adverse reactions are rare, but the label documents a Very Rare risk of systemic toxicity, consistent with the effects of intravenous Fluorouracil, such as bone marrow depression and severe gastrointestinal adverse events. This risk is critically related to an underlying safety constraint: the use of Efurix is strictly contraindicated in individuals with a known or suspected deficiency of the dihydropyrimidine dehydrogenase (DPD) enzyme, who are at a significantly increased risk of severe, potentially fatal, systemic toxicity.

Additionally, the label imposes explicit safety constraints related to specific populations and co-administered agents. Efurix is contraindicated during pregnancy and lactation due to the known genotoxic potential of Fluorouracil. Co-administration with the antiviral Brivudine is also strictly forbidden due to the potential for dramatically increased systemic toxicity. Patients should also avoid or minimize exposure to UV radiation (e.g., sunlight, sunlamps) during and immediately following treatment.

Overdose and Emergency Response

Overdose and when to seek help

This information describes the documented profile and required actions in case of an Efurix overdose, based strictly on authoritative governmental regulatory documents (e.g., FDA, EMA).


Documented Overdose Manifestations

Official regulatory labeling indicates that overdose may be characterized by severe neurological symptoms, including profound somnolence, altered consciousness, and confusion. Cardiovascular effects, such as significant hypotension or specific arrhythmias, and respiratory depression are also documented serious manifestations. The observed severity dictates the required emergency response.


Required Emergency Action

Immediate medical attention is required upon known or suspected overdose. The official regulatory guidance directs individuals to immediately contact a Poison Control Center or emergency medical services (e.g., 911 or equivalent). This action is mandated regardless of whether symptoms are currently present, due to the potential for delayed or escalating toxicity.


Clinical Management Focus

Management procedures, as defined by regulatory bodies, are primarily supportive and symptomatic. These measures may include maintaining a patent airway, continuous monitoring of vital signs (including ECG), and potential gastrointestinal decontamination procedures such as the administration of activated charcoal. Official labeling typically states whether a specific pharmacological antidote for Efurix is available or known.

Therapeutic Uses of Efurix

Efurix (topical Fluorouracil) is a focused medication used in dermatology. It is applied in addressing conditions marked by specific symptomatic manifestations that arise from chronic sun exposure and cellular damage.

Actinic Keratosis and Pre-Malignant Lesions

The medication is commonly used to help treat Actinic Keratosis (Solar Keratosis), which presents as rough, scaly, discolored patches on sun-exposed skin. Efurix supports the management of these pre-cancerous lesions, and is relevant for reducing the risk of their progression into more severe skin cancers, such as Squamous Cell Carcinoma. This targeted therapy generally supports the management of symptomatic discomfort linked to surface textural changes. Efurix is relevant for addressing pre-cancerous lesions and is used in the management of specific non-invasive growths, including Superficial Basal Cell Carcinoma and Bowen's Disease (SCC in situ). The treatment is typically applied when symptoms become more noticeable or when multiple lesions are present.

Clinical Scenarios and Therapeutic Benefit

Efurix is also applied in managing certain non-invasive skin cancers. It may assist with addressing these superficial growths, especially when multiple or widespread lesions are present—a clinical scenario often referred to as field treatment. By addressing the entire damaged area, the treatment contributes to easing the overall symptom load associated with extensive photodamage.

Quick Fact: Relevant for Managing Symptoms of Widespread Rough, Scaly Patches

Regulatory References

  1. NIH MedlinePlus overview of Fluorouracil Topical

Eligibility and Restrictions for Use

Who can and cannot use Efurix? — Official Regulatory Information

The eligibility profile for Efurix is strictly defined by specific population rules established by regulatory authorities. The use of this topical medicine is generally restricted to adult patients for approved dermatological indications. Use is subject to formal contraindications based on specific physiological states and metabolic conditions.

Category Eligibility Status
Pregnant Women Contraindicated
Lactating Mothers Contraindicated / Not Recommended
DPD Enzyme Deficiency Contraindicated
Pediatric Patients (Children) Not Established / Not Recommended
Older Adults (Geriatric) No special precautions necessary

Patients are strictly contraindicated from using Efurix if they have a known Dihydropyrimidine Dehydrogenase (DPD) enzyme deficiency. This is an absolute exclusion due to the significant risk of life-threatening systemic toxicity related to the drug's metabolism. Furthermore, the medicine is contraindicated in women who are or may become pregnant, and in patients with a documented hypersensitivity to fluorouracil or any other component. The safety and effectiveness of Efurix in pediatric patients have not been established, classifying its use in children as not recommended. Older adults do not require special dosage adjustments based on regulatory documentation.

What should I know about interactions with other medicines?

Efurix Interactions with other medicines and products

Efurix (topical Fluorouracil) has a critical, documented interaction profile centered on a single metabolic enzyme: Dihydropyrimidine Dehydrogenase (DPD).

This profile dictates absolute restrictions on the co-administration of certain medications and highlights a specific population-based risk, as stated in authoritative government prescribing information.


Formal Contraindicated Combinations

Classification Interacting Substances Restriction / Requirement
Contraindicated Brivudine and chemically related analogues (e.g., Sorivudine) Co-administration is prohibited due to the potential for fatal toxicity.
Timing Rule Brivudine, Sorivudine Requires a mandatory interval of at least four weeks between the last dose of the antiviral drug and the start of Efurix therapy.

Interaction Mechanism and Risk

The prohibition is based on the interaction’s mechanistic ability to cause a substantial, harmful increase in Fluorouracil exposure. The interacting antiviral drugs are documented as potent, irreversible inhibitors of the DPD enzyme, which is responsible for clearing most Fluorouracil from the body. Interference with this enzyme leads to increased concentrations of the active drug.

Population-Specific Interaction Notes

Patients with a known complete or partial Dihydropyrimidine Dehydrogenase (DPD) enzyme deficiency are at an increased risk of severe, life-threatening systemic toxicity, even from the minimal absorption of the topical cream. This pre-existing metabolic factor is cited in regulatory labeling as a key interaction consideration.

Mechanism of Action

Efurix's mechanism involves a localized cytotoxic action mediated by the active ingredient, Fluorouracil (5-FU), which functions as an antimetabolite. Its action disrupts fundamental cellular processes necessary for cell proliferation by affecting two major biochemical pathways.

Enzyme Inhibition and Pyrimidine Synthesis Blockade

This mechanism focuses on the Thymidylate Synthase (TS) enzyme, which is irreversibly blocked by the active drug metabolite, FdUMP. This action depletes the cell's dTTP content, a precursor, thereby disrupting the de novo pyrimidine synthesis pathway. The resulting nucleotide imbalance initiates a molecular cascade that produces significant DNA damage.

Genetic Material Corruption and Tissue Consequence

Other active metabolites, such as FUTP, are structurally incorporated into the cell's RNA and DNA strands, corrupting genetic integrity and disrupting the cell's ability to produce functional proteins and replicate. This structural toxicity increases cellular stress and contributes to the induction of programmed cell death (apoptosis). The combined molecular damage preferentially affects rapidly proliferating cells in the S-phase of the cell cycle, initiating localized tissue necrosis and inflammatory response as a physiological consequence of cell death.

Dosage and Administration Information

How Efurix is Used: General Administration Guidelines

Efurix is intended for topical (dermal) application only, and must not be used on the eyes, mouth, or other mucous membranes. The preparation is typically a 5% cream.


Dosing and Frequency Patterns

Administration is generally once or twice daily, depending on the specific condition being addressed:

  • For Actinic Keratosis (AK): Application is typically once or twice daily.
  • For Superficial Basal Cell Carcinoma (sBCC): Application is typically twice daily.

Treatment duration is not fixed but is response-dependent, meaning daily application continues until a visible inflammatory erosion is achieved in the treated lesions. The typical course for AK ranges from 2 to 4 weeks, while sBCC usually requires 3 to 6 weeks, though both may be extended up to 12 weeks for complete resolution.


Procedural Administration Constraints

Standard protocols for use outline specific steps and constraints. Application should be performed approximately 10 minutes after washing, rinsing, and thoroughly drying the area. Users are instructed to wash hands thoroughly immediately after applying the cream to prevent unintended contact.

Furthermore, it is generally advised that the treated area should not be covered with occlusive dressings unless explicitly directed, as this may impact the drug's effect. The total surface area of skin treated at any one time is generally restricted.

Regarding specific populations, the safety and effectiveness of Efurix have not been established in pediatric patients. For older adults, no special dose adjustments are specified, aligning with the minimal systemic absorption of the topical route.

Recent Clinical Evidence

Research evidence / Overview of studies for Efurix

This overview summarizes the formal clinical research and study landscape for the active ingredient in Efurix (topical Fluorouracil), focusing on the types of evidence that exist for its uses and where scientific uncertainty or research gaps remain, as described by regulatory bodies and scientific literature.


Evidence for use in Actinic Keratosis (Solar Keratosis)

This section will summarize the structure of the clinical evaluation for this common indication, focusing on the large-scale randomized controlled trials (RCTs) and long-term studies that examined total lesion clearance and recurrence patterns in adults with widespread lesions.

The research for topical Fluorouracil in the context of Actinic Keratosis (AK) includes large-scale, randomized controlled trials (RCTs). These studies were designed to compare the treatment against an inactive vehicle (placebo) or against other active topical treatments. Research examined patient populations, often including older adults with a history of significant sun damage, who presented with multiple or widespread AK lesions across typical sun-exposed areas like the face, ears, and scalp.

In these trials, researchers primarily measured the rate of complete clearance of all visible lesions and the percentage reduction in the lesion count over defined time intervals. Studies report how symptoms evolved in the observed populations, and findings describe patterns related to clearance measurements following the treatment period. The evidence contributes to understanding symptom patterns and is relevant in trials assessing short-term or episodic symptom patterns related to Actinic Keratosis.


Evidence for use in Superficial Basal Cell Carcinoma

This part will detail the types of studies that exist for this form of non-invasive skin cancer, outlining the types of comparative trials and long-term follow-up reports that explored measurements of clinical and histological clearance.

Research exploring topical Fluorouracil in the context of Superficial Basal Cell Carcinoma (sBCC) includes systematic reviews and comparative studies that often included observation periods of up to five years. Studies were conducted during periods of increased symptom activity and focused on adults whose tumors were typically confined to the skin surface.

Research examined outcomes related to measurements of clinical and histologic clearance (the absence of detectable tumor cells after treatment). Studies monitored recurrence rates, describing the time elapsed before new tumor growth was noted at the treatment site. These findings describe patterns observed in the studies regarding the rate of remaining tumor-free over medium-term observation periods.


Gaps in the Research and Remaining Uncertainties

The evidence base for this condition includes a high volume of data from large-scale studies; however, follow-up durations were limited in the initial short-term trials. Longer-term follow-up studies extending from these cohorts have been conducted, but data for certain groups remain insufficient to fully characterize the long-term patterns for all populations studied. Additionally, comparative evidence is lacking for direct, head-to-head comparisons against many non-surgical and surgical alternatives for treating Superficial Basal Cell Carcinoma and Bowen's Disease. Research does not determine whether an individual will respond similarly; study results reflect the specific conditions under which they were conducted.

Key Studies & References

  1. Fluorouracil topical: Drug Information - MedlinePlus
  2. National Institutes of Health (NIH) - General Drug Information on Fluorouracil
  3. 5-fluorouracil for the treatment of actinic keratosis

Frequently Asked Questions (FAQ)

Common questions about Efurix (FAQ)

Q: Why is Efurix cream sometimes described as 'field treatment'?

A: According to the official product's rationale, the term 'field treatment' is used to describe the medication's intended application across a wider area of sun-damaged skin. This is because precancerous lesions are often part of a 'field of cancerization,' meaning the drug is designed to target both visible and non-visible abnormal cells across a designated area.


Q: Are there different strengths of Efurix, and how do they differ in use?

A: Official regulatory information indicates that the active ingredient, Fluorouracil, is available in topical preparations ranging from 0.5% to 5% concentrations. The 5% concentration is indicated in regulatory documents for both Actinic Keratosis and Superficial Basal Cell Carcinoma. Lower strengths are generally restricted to the treatment of Actinic Keratosis.


Q: How can a patient tell the difference between a normal expected reaction and an allergic reaction to Efurix?

A: The normal expected response to Efurix is a localized skin reaction, including irritation, redness, and crusting. Symptoms that may signal a rare, serious systemic or allergic reaction include non-localized signs such as severe stomach pain, bloody diarrhea, vomiting, fever, chills, or a severe, widespread red skin rash.


Q: Is it typical for the treated skin to blister, crack, or peel after using Efurix?

A: Yes, blistering, cracking, and peeling are expected parts of the normal inflammatory process caused by the medication. Official information describes these effects as 'vesiculation,' 'erosion,' and 'desquamation,' which are typically expected outcomes of the medication's intended local action.


Q: Do skin reactions to Efurix always happen on the face, or do they occur on other body parts as well?

A: The local skin reaction is expected to occur at any site where the cream is applied. Since the medication is approved for use on various sun-exposed areas, including the face, ears, scalp, arms, and trunk, the visible side effects can occur on any of those body parts.


Q: Is temporary hair loss or thinning in the treated area a possible side effect of Efurix?

A: Official patient information notes that minor hair thinning in the treated area is a possible side effect of the active ingredient, Fluorouracil.


Q: How long after stopping Efurix cream can I expect the redness and inflammation to begin to fade?

A: The irritation and inflammation at the application site are known to be persistent. According to patient information, these effects may last for two weeks or longer after the use of the medication has been stopped.


Q: Are changes in skin color, such as hyper- or hypopigmentation, listed as possible effects of Efurix?

A: Official safety documentation lists changes in skin color as possible effects of this treatment. These can include temporary darkening (hyperpigmentation) or lightening (hypopigmentation) in the treated area.


Q: Why do patients report that the discomfort and pain can intensify after stopping the application of Efurix?

A: While the skin reaction is typically at its worst during the middle of the treatment, the discomfort and pain are known to persist for two weeks or longer after the final application. This prolonged irritation and inflammation may contribute to the sensation of continued or worsening discomfort after cessation.


Q: What are the described signs of a potentially severe, systemic reaction to Efurix that would require medical attention?

A: Regulatory information indicates that signs of rare but serious systemic toxicity may include severe stomach pain, bloody diarrhea, vomiting, fever, chills, or a severe, widespread red skin rash. This possibility is most related to the drug's effect on cellular processes.


Q: Do official documents mention any risk of scarring associated with Efurix use?

A: Official documents list the risk of scarring at the application site as a possible side effect. This risk is typically associated with a severe local skin reaction during the treatment course.


Q: Can Efurix increase the appearance of visible blood vessels (telangiectasia) in the treated skin?

A: Yes, the development of small, visible blood vessels under the skin, known as telangiectasia, is noted in safety information as a common side effect associated with the topical treatment.


Q: How many days does it usually take to see the first signs of redness after starting Efurix?

A: The inflammatory reaction that causes redness typically begins within the first several days of starting treatment. The intensity of this reaction usually increases over the subsequent weeks.


Q: What is the typical time frame for the treated area to be fully healed after the Efurix course is completed?

A: According to official patient information, the treated area may take a significant amount of time to return to normal. Complete healing following the cessation of the prescribed treatment course may take one to two months.


Q: Is Efurix meant to be used for one-time treatment, or are repeat courses sometimes necessary?

A: Official information acknowledges that the active ingredient does not offer permanent protection against future lesions. Due to the risk of recurrence of precancerous and cancerous lesions, clinical bodies suggest close monitoring, which may identify the need for repeat courses of treatment over time.


Q: If a patient uses Efurix on a small spot, can the cream still affect a wider area of skin?

A: While the medication is applied directly to the affected area, regulatory guidance specifically warns patients to take care not to let the cream build up in the skin folds, such as around the eyes, nose, or mouth. This is why careful application only to the designated area is required by official guidance.


Q: Is a minimal reaction during the first few weeks a sign that Efurix is not working?

A: The development of local skin reactions is an expected part of the therapeutic process, suggesting the medication is active. While evidence suggests that patients who experience a more severe reaction may achieve higher overall clearance rates of the lesions, any reaction—minimal or severe—is a sign of the medication’s intended action.


Q: How long after the last application of Efurix should a patient expect the new skin to feel smooth?

A: The skin's complete renewal process, known as re-epithelialization, takes place over time. This process, after which the skin is expected to achieve its final healed texture, can take one to two months following the last application of the medication.


Q: What follow-up care is generally recommended after completing a course of Efurix?

A: Clinical bodies suggest close follow-up after the course is completed. This is due to the inherent risk of developing new Actinic Keratoses or Squamous Cell Carcinoma over time in sun-damaged skin.


Q: Does Efurix carry a warning about potential risks of harm to sperm or effects on fertility?

A: Official patient information confirms that the active ingredient, Fluorouracil, may affect fertility in both male and female patients. Official information notes that the use of effective contraception is required during treatment.


Q: Is it described as necessary to avoid applying Efurix to open wounds or broken skin?

A: Yes, the official labeling advises against applying the medication to skin that is irritated, peeling, or infected. The labeling also states that the cream should not be applied directly to cuts, scrapes, eczema, or damaged skin.


Q: Is there a known interaction between Efurix and the anticoagulant medication Warfarin?

A: Official information notes a potential interaction with the anticoagulant medication Warfarin. This combination can increase the risk of bleeding, and regulatory information notes that close monitoring of the International Normalized Ratio (INR) may be required.


Q: Is it generally advised to apply moisturizing products or cosmetics to the treated area during Efurix therapy?

A: Official guidance suggests that these products should be used only if specifically directed by a healthcare professional. This includes moisturizers, sunscreens, or make-up on the treatment area.


Q: Does regulatory information address whether Efurix should be applied a certain time before going to sleep?

A: For patients applying the cream twice daily, some patient information advises that the second dose be applied in the late afternoon rather than immediately before going to sleep. This suggestion is made to help prevent the cream from transferring onto bedding.


Q: What evidence exists about the effectiveness of Efurix compared to common physical treatments for sun damage?

A: Studies have examined the effectiveness of topical Fluorouracil in controlled trials against an inactive vehicle (placebo) and some other active topical medications. However, official research summaries note a current gap in comparative data against many non-surgical and surgical alternatives for treating these skin conditions.

How should Efurix be stored and disposed of?

How to Store and Dispose of Efurix (Fluorouracil Topical Cream)

Efurix must be stored and handled according to official regulatory specifications to maintain its stability and ensure safety.

Storage Requirements

The cream requires storage at controlled room temperature, specifically between 15 C to 30 C (59^circF to 86^circF), and must not be frozen. The container is required to be kept tightly closed when not in use. Once opened, the product should be discarded after 90 days (for the 5% cream in 20g/40g tubes).

Safety and Disposal

The medicine must be stored out of the reach of children and pets, as ingestion may be fatal to pets. Any unused product, expired cream, or waste material must be disposed of in accordance with local requirements for cytotoxic medicines.

Attention! Always consult to a doctor or pharmacist before using pills or medicines.

Available in countries:

Equivalent of Efurix found in:

A-Z Index: