Mefoxin

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Mefoxin

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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 Mefoxin

Property Description
Active ingredient Cefoxitin Sodium
Form Sterile powder for injection
Pharmacological Class Cephamycin (Second-Generation Antibiotic)
Common Use Treating serious bacterial infections
Origin Semisynthetic

What Type of Antibiotic is Mefoxin (Cefoxitin)?

Mefoxin is a prescription-only, semisynthetic beta-lactam antibiotic whose active ingredient is Cefoxitin Sodium, classifying it as a second-generation cephalosporin. Specifically, Cefoxitin belongs to the cephamycin subgroup, an antimicrobial agent derived from a naturally occurring structure. The unique chemical features of Cefoxitin Sodium provide stability against bacterial defense enzymes, such as beta-lactamases, which distinguishes it from many earlier antibiotics.

Cefoxitin is recognized for its efficacy against certain anaerobic bacteria, often utilized when resistance to other common antibiotics is a concern. The structural features of Cefoxitin place it within the cephamycin class due to its methoxy group, which provides critical beta-lactamase stability.

Mefoxin's Composition, Origin, and Pharmaceutical Form

The medicine is supplied as a sterile powder for injection, a single-component product containing Cefoxitin Sodium, which is intended exclusively for reconstitution in a suitable sterile aqueous diluent. This specific formulation produces a solution for injection that must be administered via the parenteral route, which means it is delivered either intravenously or intramuscularly. This method ensures that the necessary therapeutic concentration of the Cefoxitin Sodium reaches the systemic circulation quickly, making it suitable for intervention in acute bacterial illnesses where rapid systemic effect is medically required.

General Purpose and High-Level Action of Mefoxin

The general purpose of Mefoxin is to resolve serious infections by providing rapid, definitive microbial control. Its action is primarily bactericidal, meaning it actively kills susceptible bacteria by interfering with their cell wall synthesis. As a broad-spectrum agent, Mefoxin's ability to resist common bacterial defense mechanisms ensures it remains a reliable tool for eliminating the underlying microbial cause of illness.

Regulatory References

  1. NIH

What side effects are possible with Mefoxin?

Possible Side Effects and Safety Information

The safety profile for Mefoxin (Cefoxitin Sodium) is based on classifications from governmental regulatory documents, which categorize known adverse reactions by frequency and physiological system. Common adverse reactions (occurring in 1% to 10% of individuals) include transient changes in blood counts, such as eosinophilia and leukopenia, as well as diarrhea and local reactions at the injection site, like thrombophlebitis.


System-Organ-Class Safety Overview

Adverse effects are formally grouped into system-organ classes, including Gastrointestinal Disorders (diarrhea, nausea), Blood and Lymphatic System Disorders (various blood cell changes), Skin and Subcutaneous Tissue Disorders (rash, pruritus), and Renal and Urinary Disorders (elevations in BUN/Creatinine).

Serious Adverse Reactions and Restrictions

Regulatory documents highlight rare but serious adverse reactions, notably Anaphylaxis (a severe allergic reaction) and Pseudomembranous Colitis, a serious intestinal condition that can occur during or up to two months after treatment. Severe skin reactions, such as Toxic Epidermal Necrolysis (TEN), are also documented.

Cefoxitin is formally contraindicated in patients with a history of hypersensitivity to Cefoxitin or other cephalosporin-class antibiotics. Caution is also noted for patients with a penicillin allergy due to the potential for cross-allergenicity.


Population-Specific Safety Notes

For patients with Renal Impairment, regulatory guidance emphasizes the need for dose adjustment. Failure to manage the dose appropriately in these individuals can lead to drug accumulation and subsequent Central Nervous System (CNS) toxicity, including the documented risk of seizures. Additionally, prolonged use of this medicine may result in the overgrowth of non-susceptible organisms, known as superinfection.

Overdose and Emergency Response

The official regulatory documentation for Cefoxitin Sodium (Mefoxin) details specific, documented manifestations of overdose and mandatory emergency actions. Overdose presentations are primarily characterized by signs of Central Nervous System (CNS) toxicity, including convulsions and seizures, which may progress to states of decreased consciousness, stupor, and coma. The renal system is also a documented target, with potential severe outcomes such as acute renal tubular necrosis and acute renal failure noted in regulatory labels. This severe risk profile is heightened in patients with renal insufficiency or renal failure, as impaired drug clearance significantly increases the potential for CNS toxicity.

Due to these potential life-threatening manifestations, regulatory authorities explicitly mandate that individuals seek immediate medical attention for any suspected overdose or when severe symptoms are observed. The management approach is defined by the official statement that no specific antidote is known. Consequently, the mandated procedures focus on providing general supportive therapy and continuous patient monitoring. In cases involving impaired renal function, dialysis may be performed to aid in the elimination of the drug, as documented in official prescribing information.

Therapeutic Uses of Mefoxin

What Mefoxin Treats: Main Uses and Benefits

Mefoxin is commonly used across conditions presenting with acute or disruptive symptom patterns, often related to serious bacterial infections. Its therapeutic application focuses on managing systemic symptoms (like high fever and malaise) and symptoms related to inflammatory or irritative states. The drug is relevant in clinical settings for treating specific conditions, including septicemia, severe lower respiratory tract infections (pneumonia), complex intra-abdominal infections (peritonitis, abscesses), and acute gynecological infections (Pelvic Inflammatory Disease). These therapeutic applications contribute to easing the overall symptom load during acute episodes and assist with maintaining functional stability during periods of heightened discomfort.

It is also widely used to provide prophylactic support in certain surgical contexts to manage the risk of postoperative infection.

“The medication helps address symptom clusters that may become intense or disruptive, especially in infections associated with heightened symptoms.”


Quick Fact: Relief for Systemic Discomfort

Mefoxin is commonly used in scenarios where symptoms related to systemic imbalance, such as fever and malaise, may benefit from supportive management to help patients cope more steadily with symptom fluctuations.

Eligibility and Restrictions for Use

Official Eligibility Rules for Mefoxin (Cefoxitin)

The eligibility profile for Mefoxin is strictly defined by official regulatory documentation, outlining populations who are contraindicated and those requiring conditional use.

The medicine is contraindicated in any patient with a documented history of hypersensitivity or severe allergic reaction to Cefoxitin itself. This absolute prohibition also extends to patients with known allergies to the cephalosporin class of antibiotics or other beta-lactam antibacterial drugs, due to the risk of cross-reactivity.

Regarding age, Mefoxin is approved for use in adults and pediatric patients 3 months of age and older. Safety and efficacy have not been established in infants younger than 3 months. In older adults, use is acceptable, but eligibility is contingent upon an assessment of kidney function.

Conditional use applies to certain physiological states. Patients with impaired renal function must receive a modified dosage regimen to prevent drug accumulation. Similarly, official labeling advises caution for patients with a history of gastrointestinal disease, such as colitis. During pregnancy, use is limited to situations where it is clearly needed, as adequate human data are unavailable; caution is also advised for women who are breastfeeding, as the drug is excreted in human milk.

What should I know about interactions with other medicines?

The official regulatory profile for Mefoxin (Cefoxitin) focuses on interactions that modify the medicine’s concentration in the body and those that increase the risk of specific organ toxicity. The label classifies the interaction with Probenecid as a pharmacokinetic interaction, since this drug inhibits the renal tubular secretion of Cefoxitin. This officially results in higher and prolonged serum levels of Cefoxitin, increasing the exposure.

A distinct pharmacodynamic interaction is documented with Aminoglycoside Antibiotics (such as Amikacin and Gentamicin). Co-administration of these substance classes is associated with an officially noted increased risk of nephrotoxicity (additive damage to the kidneys).

The medicine is also subject to constraints related to laboratory testing, a recognized procedural interaction. Specifically, the presence of Cefoxitin is documented to interfere with certain analytical methods. This includes the measurement of serum and urine creatinine levels by the Jaffé reaction, which can produce falsely increased values. Additionally, it interferes with the measurement of urinary 17-hydroxy-corticosteroids using the Porter-Silber reaction, leading to falsely elevated results.

No absolute drug-drug contraindications or mandatory timing requirements for administration separation are formally specified in the official regulatory documentation.

Mechanism of Action

Mefoxin's mechanism is fundamentally bactericidal, initiated by the covalent inhibition of critical bacterial enzymes. The primary biological targets are the Penicillin-Binding Proteins (PBPs), specifically their transpeptidase and carboxypeptidase domains. Cefoxitin acts as a structural mimic of the peptidoglycan precursor, allowing it to bind irreversibly to the active site of the PBP and block the final cross-linking step in the bacterial cell wall synthesis pathway. The resulting structural compromise triggers a subsequent autolytic cascade within the bacterium, activating internal destructive enzymes. This combined action of arrested synthesis and active degradation leads to rapid and irreversible cell lysis, which constitutes the drug's physiological cell-killing effect. Furthermore, the molecule's unique 7alpha-methoxy group provides steric stability, supporting the mechanism's functional integrity by conferring intrinsic resistance against inactivation by bacterial beta-lactamase enzymes.

Dosage and Administration Information

Official Administration Guidelines for Cefoxitin

Mefoxin, which contains Cefoxitin Sodium, is exclusively administered via the parenteral route, meaning it must be given by intravenous (IV) injection or infusion or by intramuscular (IM) injection. The medicine is supplied as a sterile powder in vials equivalent to 1 g, 2 g, or 10 g of Cefoxitin, which requires reconstitution with an appropriate sterile diluent prior to use.

Dosing and Frequency

The dosage is determined by the severity of the infection, with the total daily dose for adults not exceeding 12 grams. Standard adult treatment regimens for moderate to severe infections range from 1 g every 4 hours to 2 g every 6 to 8 hours. For surgical infection prophylaxis, a 2 g IV dose is typically administered just prior to surgery, with subsequent doses every 6 hours for up to 24 hours.

Specific Use Instructions

IV administration may be a slow direct injection over 3 to 5 minutes or an intermittent infusion over a longer period. IM injection must be given deep into a large muscle mass. For pediatric patients three months of age and older, the total daily dose is calculated in a range of 80 to 160 mg/kg/day, divided and given every 4 to 6 hours. For adults with impaired renal function, an initial loading dose is followed by a modified maintenance dose and interval based on the patient’s calculated creatinine clearance.

Recent Clinical Evidence

Mefoxin: Recent Clinical Evidence

Research Evidence for Studied Use in Systemic and Respiratory Infections

Mefoxin has been extensively studied for its use in clinical situations involving serious systemic infections, such as those found in the bloodstream, and severe lower respiratory tract infections, like pneumonia. The research base includes Randomized Comparative Trials (RCTs) where Mefoxin was evaluated in comparison to other existing antibiotics. Researchers monitored clinical outcomes related to physical discomfort and the measured clearance of pathogenic bacteria from the site of infection. Findings describe patterns observed in the studies over the short period of active antibiotic treatment.

Research Evidence for Studied Use in Complex Intra-abdominal and Gynecological Infections

Evidence supporting Mefoxin's use in complex abdominal and acute pelvic infections is drawn from Prospective, Randomized Comparative Trials and observational studies. These studies were conducted during periods of increased symptom activity, monitoring clinical success response and microbiological response. A structural limitation documented in this research area is the fact that the antibiotic class lacks activity against certain co-pathogens (such as Chlamydia trachomatis), and this was addressed in the studies by co-administering a second agent.

Research Evidence for Reducing Infection Risk in Surgery (Prophylaxis)

Mefoxin was evaluated in multiple prospective and often blinded clinical trials, as well as systematic reviews, to assess its use in reducing the risk of postoperative infection. The research specifically examined patients undergoing certain procedures like hysterectomy or Cesarean section, focusing on risk reduction. Studies tracked the incidence of Surgical Site Infections (SSI) and the relationship between the timing of administration and the measured short-term outcomes.

Evidence Gaps and Limitations

For Mefoxin, like many antibiotics used for acute illness, the majority of the clinical research focuses on immediate short-term results. As a result, there is limited information for long-term outcomes regarding the durability of the effect beyond the immediate post-treatment period (e.g., 30 days). Data for certain patient groups, such as pediatric populations or older adults with significant comorbidities, remains insufficient or comes from smaller trials. Research describes the need for ongoing monitoring of its profile against evolving resistance patterns in hospital settings.

Frequently Asked Questions (FAQ)

Common questions about Mefoxin (FAQ)


Q: Is Mefoxin the same type of medicine as penicillin?

A: Mefoxin is classified as a cephamycin, which is part of the larger group of beta-lactam antibiotics, similar to penicillin. However, the official product information notes that caution is needed for patients with a known penicillin allergy due to the potential for cross-allergenicity.

Q: What happens if Mefoxin is stopped early?

A: Regulatory documents describe risks, such as serious intestinal conditions, that can occur during or after antibiotic treatment. Completing the prescribed course is important to address the underlying infection. Official warnings include the risk of Pseudomembranous Colitis or C. difficile-associated diarrhea (CDAD), which may occur up to two months after the medicine is stopped.

Q: What is the generic name for Mefoxin?

A: The active substance in Mefoxin is Cefoxitin Sodium. Cefoxitin is the established generic name for this antibacterial drug. The medicine is supplied as a sterile powder which is then prepared as a solution for injection.

Q: Does Mefoxin treat viruses or only bacteria?

A: Mefoxin is officially identified as an antibacterial agent and an antibiotic. Its mechanism of action involves actively killing susceptible bacteria that cause serious infections. It is not indicated for the treatment of viral infections.

Q: What is the difference between prophylaxis and treatment use of Mefoxin?

A: Official guidance describes two primary uses. Prophylaxis is the use of the medicine just before and shortly after certain surgical procedures to reduce the risk of a post-operative infection. Treatment use refers to administering the medicine to resolve an infection that is already established and causing illness.

Q: How quickly does Mefoxin start to work?

A: Following intravenous administration, regulatory documents indicate that serum concentrations reach effective levels immediately. Pharmacokinetic studies show that the drug has a short half-life, approximately 41 to 59 minutes in adults with normal kidney function. The half-life indicates that the amount of active drug is rapidly reduced, primarily through the kidneys.

Q: Is Mefoxin considered safe for older adults?

A: Official information indicates that Mefoxin is acceptable for use in older adults. However, because older individuals are more likely to have age-related kidney function issues, a modified dosage is often necessary. Dose adjustment is typically required to help prevent drug accumulation and the potential for toxicity, such as central nervous system side effects.

Q: How long does Mefoxin typically stay in the body after the last dose?

A: In adults with normal kidney function, the official documents state that the drug has an elimination half-life of approximately 41 to 59 minutes. The half-life indicates that the amount of active drug is rapidly reduced, primarily through the kidneys.

Q: Can Mefoxin change the results of certain lab tests?

A: Yes, official regulatory documents state that the presence of Mefoxin in high concentrations may interfere with certain analytical methods used in laboratory tests. This includes potentially producing falsely elevated results when measuring creatinine (a kidney function marker) and urinary 17-hydroxy-corticosteroids.

Q: Is Mefoxin used for treating UTIs (urinary tract infections)?

A: Yes, official regulatory documents list Mefoxin as being indicated for the treatment of urinary tract infections. This includes UTIs that are caused by specific, susceptible strains of bacteria.

Q: Is Mefoxin used for treating sexually transmitted infections?

A: Yes, the official list of indications includes the use of Mefoxin for treating uncomplicated gonorrhea (cervical, urethral, and rectal). When used for this specific purpose, the medicine is typically administered alongside another medication called Probenecid.

Q: Is there a maximum time Mefoxin can be safely used?

A: For the purpose of surgical infection prevention (prophylaxis), the regulatory guidance limits use to no more than 24 hours. For the treatment of established infections, official documents suggest maintaining therapy for at least 10 days, but the duration for active treatment depends on the specific type of infection being treated.

Q: Does Mefoxin cause confusion or changes in mood?

A: Regulatory documents mention the risk of confusion and seizures as part of potential Central Nervous System (CNS) toxicity. This risk is specifically documented to increase if the dose is not correctly adjusted for patients who have impaired kidney function, leading to drug accumulation.

Q: Why might a doctor choose Mefoxin over another antibiotic?

A: Official documents highlight Mefoxin’s unique chemical structure, which provides stability against bacterial beta-lactamase enzymes. This stability is noted as a key characteristic, as it enables the medicine to remain effective in situations where bacteria may have developed resistance to other types of antibiotics.

Q: Can Mefoxin be used during pregnancy?

A: Official guidance advises that Mefoxin should be used during pregnancy only when it is clearly needed. Caution is advised due to the lack of adequate human data to establish safety during pregnancy. Animal studies have not shown evidence of fetal harm.

Q: Is it safe to breastfeed while receiving Mefoxin?

A: Official documents advise caution for breastfeeding women, noting that the drug is excreted into human milk and comprehensive data on the effects on the nursing infant is lacking.

Q: What information does the FDA provide about Mefoxin?

A: The Food and Drug Administration (FDA) provides the detailed, legally binding official label for Mefoxin. The FDA label includes information on the drug's approved indications (what it treats), contraindications (when it should not be used), known side effects, recommended dosage and administration practices, and storage guidelines.

Q: Are there known drug classes that interact with Mefoxin?

A: Regulatory documents describe known interactions with two classes of medicine. Probenecid is noted to increase the amount of Mefoxin in the body. Aminoglycoside Antibiotics are documented to potentially increase the risk of nephrotoxicity (harm to the kidneys) when co-administered with Mefoxin.

Q: Why is Mefoxin sometimes combined with other medications?

A: The reason for combination is often related to Mefoxin's spectrum of activity. Regulatory documents note that in treating certain complex infections, Mefoxin may be combined with a second agent because it lacks activity against some co-pathogens, such as Chlamydia trachomatis.

Q: Is Mefoxin ever used outside of a hospital setting?

A: The medicine is officially administered only via the intravenous (IV) injection/infusion or intramuscular (IM) injection routes. Official administration routes are restricted to intravenous or intramuscular injection, which requires professional preparation and delivery in a clinical setting.

How should Mefoxin be stored and disposed of?

Storage and Disposal of Mefoxin (Cefoxitin for Injection)

Official regulations require the dry powder to be stored below 30°C and away from temperatures exceeding 50°C. The dry material may darken, but this does not affect potency.

Stability After Reconstitution

Once reconstituted, the solution's potency is time and temperature-dependent. Thawed solutions must not be refrozen.

Storage Environment Maximum Stability Time
Room Temperature (25°C or below) 24 hours
Refrigeration (below 5°C) One week
Frozen State At least 30 weeks

Any unused solutions or frozen material must be discarded after the stability period has passed. The container must be inspected; discard the injection if seals are not intact or if an insoluble precipitate is visible.

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

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