Negaban: Uses, Dosage & Side Effects

What Is Negaban and What Is It Used For?

Negaban contains the active substance temocillin, a semi-synthetic penicillin antibiotic that was first developed in the early 1980s by Beecham Pharmaceuticals. Temocillin is the 6-alpha-methoxy derivative of ticarcillin, meaning it has a methoxy group (-OCH3) attached at the 6-alpha position of the penicillin nucleus. This seemingly small structural modification has profound consequences for the drug's pharmacological properties, as it confers remarkable stability against enzymatic hydrolysis by virtually all serine beta-lactamases while maintaining bactericidal activity against a focused range of Gram-negative pathogens.

Like all beta-lactam antibiotics, temocillin works by inhibiting bacterial cell wall synthesis. Specifically, it binds to penicillin-binding proteins (PBPs) in the bacterial cell membrane, which are enzymes responsible for the final steps of peptidoglycan cross-linking during cell wall construction. When temocillin binds to PBPs, it prevents the formation of the cross-links that give the bacterial cell wall its structural integrity. Without a functional cell wall, the bacterium is unable to maintain osmotic pressure and undergoes lysis (bursting), resulting in cell death. Temocillin primarily binds to PBP3 in Gram-negative bacteria, which is involved in cell division and septum formation. This binding leads to the formation of filamentous bacterial cells that are unable to divide and ultimately undergo lysis.

What makes temocillin truly unique among beta-lactam antibiotics is its extraordinary resistance to enzymatic degradation. Beta-lactamases are enzymes produced by bacteria that cleave the beta-lactam ring, which is the core structural element responsible for the antibacterial activity of penicillins, cephalosporins, and carbapenems. The production of beta-lactamases is one of the most important mechanisms of antibiotic resistance worldwide, and the proliferation of extended-spectrum beta-lactamases (ESBLs), AmpC cephalosporinases, and carbapenemases represents a critical global health threat. The 6-alpha-methoxy group on temocillin sterically hinders the approach of beta-lactamase enzymes to the beta-lactam ring, effectively shielding it from hydrolysis. As a result, temocillin retains its antibacterial activity against organisms that produce:

• Extended-spectrum beta-lactamases (ESBLs): Including CTX-M, TEM, and SHV types, which are the most prevalent ESBLs globally. ESBL-producing E. coli and Klebsiella pneumoniae are responsible for a substantial proportion of multidrug-resistant urinary tract and bloodstream infections.
• AmpC cephalosporinases: Both chromosomal (found in Enterobacter, Citrobacter freundii, Serratia, and Morganella species) and plasmid-mediated AmpC enzymes. These enzymes confer resistance to third-generation cephalosporins but do not affect temocillin.
• Certain carbapenemases: Notably KPC (Klebsiella pneumoniae carbapenemase) and OXA-48 type enzymes. While temocillin is not formally indicated for the treatment of carbapenemase-producing organisms, in vitro data and emerging clinical evidence suggest it may retain activity against some KPC and OXA-48 producers, particularly in the urinary tract where drug concentrations are very high.

The spectrum of activity of temocillin is focused on Gram-negative Enterobacterales. Susceptible organisms typically include Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, Proteus mirabilis, Proteus vulgaris, Citrobacter koseri, Citrobacter freundii, Enterobacter cloacae, Enterobacter aerogenes, Morganella morganii, Providencia species, and Serratia marcescens. However, temocillin has no clinically useful activity against Gram-positive bacteria (such as Staphylococcus, Streptococcus, or Enterococcus species), anaerobic bacteria, or non-fermenting Gram-negative organisms (including Pseudomonas aeruginosa and Acinetobacter baumannii). This narrow but targeted spectrum is actually an advantage from an antimicrobial stewardship perspective, as it allows clinicians to treat specific Gram-negative infections without the broad ecological impact associated with carbapenems or broad-spectrum penicillins.

Negaban is used in clinical practice for the treatment of various infections caused by susceptible Gram-negative bacteria, including:

• Urinary tract infections (UTIs): Including uncomplicated and complicated UTIs, cystitis, and pyelonephritis. Temocillin achieves exceptionally high urinary concentrations (often exceeding 500 mg/L), making it particularly effective for UTIs, including those caused by ESBL-producing organisms.
• Bloodstream infections (bacteremia): Including bacteremia secondary to urinary, biliary, or intra-abdominal sources. Several retrospective and prospective studies have demonstrated clinical outcomes comparable to carbapenems for ESBL-producing Enterobacterales bacteremia.
• Lower respiratory tract infections: Including nosocomial pneumonia caused by susceptible Gram-negative pathogens, although lung tissue penetration is relatively limited compared to urinary concentrations.
• Wound and soft tissue infections: When caused by susceptible Gram-negative organisms.
• Intra-abdominal infections: Typically in combination with an anti-anaerobic agent such as metronidazole, since temocillin lacks activity against anaerobes.

What Should You Know Before Taking Negaban?

Contraindications

The primary contraindication to Negaban use is known hypersensitivity (allergy) to temocillin, to any other penicillin antibiotic, or to any of the excipients in the formulation. Penicillin allergy affects approximately 1–10% of the general population, although true IgE-mediated penicillin allergy confirmed by skin testing or oral challenge is considerably less common (estimated at 1–2%). If you have experienced a previous allergic reaction to any penicillin (such as amoxicillin, ampicillin, flucloxacillin, or piperacillin), you should inform your healthcare provider before receiving Negaban.

Severe allergic reactions to penicillins, including anaphylaxis, angioedema (swelling of the face, lips, tongue, or throat), and severe skin reactions (such as Stevens-Johnson syndrome or toxic epidermal necrolysis), are rare but potentially life-threatening. If you have a history of anaphylaxis to any penicillin, Negaban should not be used unless the potential benefit clearly outweighs the risk and the drug is administered under close medical supervision with resuscitation equipment available.

Cross-reactivity between penicillins and cephalosporins or carbapenems exists but is relatively uncommon. The estimated rate of cross-reactivity between penicillins and cephalosporins is approximately 1–2% based on modern studies (significantly lower than the historically quoted 10%). If you have a history of a mild penicillin allergy (such as a non-severe rash), your doctor may still consider using Negaban with appropriate monitoring. However, if you have experienced a severe or immediate-type allergic reaction to any beta-lactam antibiotic, alternative non-beta-lactam antibiotics should generally be considered.

Warnings and Precautions

Before starting treatment with Negaban, your healthcare provider should be aware of the following:

• Renal impairment: Temocillin is primarily eliminated by the kidneys. In patients with reduced kidney function (creatinine clearance below 60 mL/min), dose adjustment or extension of the dosing interval is necessary to prevent drug accumulation and potential toxicity. Your doctor will assess your kidney function with blood tests before and during treatment.
• Sodium content: Each 1 g vial of Negaban contains approximately 4.4 mmol (approximately 101 mg) of sodium as temocillin sodium. This should be taken into account for patients on a sodium-restricted diet, patients with heart failure, or those with conditions requiring sodium restriction. In patients receiving high doses or prolonged treatment, the cumulative sodium load may be clinically significant.
• History of gastrointestinal disease: As with all antibiotics, temocillin may alter the normal gut flora and potentially lead to overgrowth of resistant organisms. Clostridioides difficile-associated diarrhea (CDAD) can occur during or after antibiotic treatment, ranging from mild diarrhea to life-threatening pseudomembranous colitis. If significant diarrhea develops during treatment with Negaban, the diagnosis of CDAD should be considered. Notably, temocillin has a relatively narrow spectrum, which may result in less disruption to the gut microbiome compared to broad-spectrum agents such as carbapenems or fluoroquinolones.
• Seizure risk: High-dose penicillins, particularly in patients with renal impairment, can lower the seizure threshold. While seizures have not been prominently associated with temocillin at standard doses, patients with a history of seizures or conditions predisposing to seizures (such as renal failure or meningitis) should be monitored.
• Laboratory test interference: Temocillin may cause false-positive results in certain urinary glucose tests that use copper reduction methods (such as Benedict’s solution or Clinitest tablets). Patients with diabetes who monitor their urinary glucose should use enzymatic glucose oxidase-based methods during treatment.

Pregnancy and Breastfeeding

There are limited data on the use of temocillin during human pregnancy. Animal reproductive toxicity studies have not demonstrated teratogenic effects, but as with all medications, Negaban should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Penicillin antibiotics as a class are generally considered among the safest antibiotics for use during pregnancy, and temocillin is expected to share this favorable safety profile. However, the decision should be made by the treating physician based on the severity of the infection and the availability of alternative treatments.

It is not known whether temocillin is excreted in human breast milk. Penicillins are generally found in breast milk in small amounts. The potential effects on the breastfed infant include modification of the intestinal flora, potential for allergic sensitization, and risk of diarrhea or oral thrush. If treatment with Negaban is necessary during breastfeeding, the potential benefits and risks should be discussed with your healthcare provider. In most cases, the small amounts of antibiotic that may be present in breast milk are unlikely to cause significant harm to the nursing infant.

Children and Adolescents

Clinical experience with temocillin in pediatric patients is limited. Negaban is generally licensed for use in adults and may be used in children on specialist advice, typically at a dose of 25–50 mg/kg every 12 hours (depending on the severity of infection and local guidelines). Neonates and infants may require adjusted dosing intervals due to immature renal function. The decision to use Negaban in children should be made by a specialist in pediatric infectious diseases, taking into account the specific pathogen, site of infection, and availability of alternative antibiotics with established pediatric dosing data.

Elderly Patients

No specific dose adjustment is required for elderly patients with normal renal function. However, since kidney function often declines with age, renal function should be assessed before starting treatment and doses adjusted according to creatinine clearance. Elderly patients may also be more susceptible to adverse effects and should be monitored closely during treatment.

How Does Negaban Interact with Other Drugs?

As a penicillin antibiotic, temocillin shares the general drug interaction profile of the penicillin class. Penicillins are not metabolized by hepatic cytochrome P450 (CYP) enzymes but are primarily eliminated by renal excretion through a combination of glomerular filtration and active tubular secretion. This means that drug interactions involving CYP enzyme inhibition or induction are generally not relevant for temocillin. However, interactions at the level of renal tubular transport and pharmacodynamic interactions should be considered.

The following table summarizes the most important drug interactions to be aware of when receiving Negaban:

Major Interactions

Probenecid is the most clinically significant interacting drug with temocillin. Probenecid is a uricosuric agent used in the treatment of gout that works by inhibiting the organic anion transporters (OATs) in the renal proximal tubule. These same transporters are responsible for the active tubular secretion of temocillin. When probenecid is administered concomitantly with temocillin, it competitively inhibits the renal tubular secretion of temocillin, resulting in higher and more prolonged serum concentrations. The half-life of temocillin may be extended by approximately 50% in the presence of probenecid. While this interaction has historically been used therapeutically (to boost penicillin levels), it is generally recommended to avoid concurrent use or to reduce the temocillin dose to prevent accumulation and potential adverse effects.

Methotrexate is another important interaction to consider. Penicillins, including temocillin, can reduce the renal clearance of methotrexate by competing for tubular secretion. This can lead to elevated methotrexate levels and an increased risk of methotrexate toxicity, which includes severe myelosuppression (dangerously low blood cell counts), mucositis, hepatotoxicity, and nephrotoxicity. If Negaban must be used in a patient receiving methotrexate, serum methotrexate levels should be monitored closely, and dose adjustments should be made as needed. This interaction is most relevant for patients receiving high-dose methotrexate therapy for oncological indications.

Minor Interactions

The interaction between temocillin and oral anticoagulants (such as warfarin) is a class effect shared by many antibiotics. By altering the composition of the intestinal microbiome, antibiotics can reduce the bacterial production of vitamin K, which is a cofactor essential for the hepatic synthesis of clotting factors II, VII, IX, and X. This can result in enhanced anticoagulant effect and an elevated International Normalized Ratio (INR), potentially increasing the risk of bleeding. While this interaction is generally mild and not universally observed, patients on warfarin should have their INR monitored more frequently during and shortly after a course of Negaban, with warfarin dose adjustments made as necessary.

The combination of temocillin with aminoglycoside antibiotics (such as gentamicin, amikacin, or tobramycin) can be therapeutically advantageous, as the two classes of antibiotics often exhibit synergistic bactericidal activity against Gram-negative organisms. However, penicillins and aminoglycosides are physically incompatible when mixed in the same intravenous solution, with the penicillin potentially inactivating the aminoglycoside. For this reason, temocillin and aminoglycosides should always be administered through separate intravenous lines, and the line should be flushed between the two drugs.

What Is the Correct Dosage of Negaban?

Negaban is supplied as a white to off-white powder in single-dose vials containing temocillin 1 g (as temocillin sodium). The powder must be reconstituted with an appropriate diluent before administration. For intravenous injection, the powder is dissolved in 10–20 mL of Water for Injections or 0.9% Sodium Chloride and administered as a slow bolus over 3–4 minutes. For intravenous infusion, the reconstituted solution is further diluted in 50–100 mL of a compatible infusion fluid (such as 0.9% Sodium Chloride or 5% Glucose) and infused over 20–30 minutes. For intramuscular injection, the powder is reconstituted in 2 mL of Water for Injections or 1% Lidocaine Hydrochloride solution (to reduce injection site pain) and administered by deep intramuscular injection into a large muscle such as the gluteus maximus.

Adults

The choice of dose depends on the type and severity of the infection, the causative pathogen and its susceptibility, and the site of infection. For most clinical indications, the standard dose is 2 g every 12 hours by intravenous administration. Some experts advocate for higher doses (2 g every 8 hours) or continuous infusion regimens for deep-seated infections or when treating organisms with higher MICs, although these regimens are not universally established and should be guided by local microbiology and infectious disease expertise.

Children

Pediatric dosing of temocillin is not well established in formal clinical trials, and use in children should be guided by a specialist in pediatric infectious diseases. When used, the generally recommended dose for children is 25–50 mg/kg body weight every 12 hours by intravenous administration. The total daily dose should not normally exceed 4 g (equivalent to the maximum adult dose). Neonates and young infants may require extended dosing intervals (e.g., every 8–12 hours for neonates older than 7 days, or every 12 hours for neonates younger than 7 days) due to immature renal function and reduced drug clearance. Pediatric dosing should always be calculated based on the child's actual body weight and adjusted according to renal function.

Elderly

No specific dose adjustment is required for elderly patients with preserved renal function. However, age-related decline in kidney function is common and should be assessed before starting treatment. The Cockcroft-Gault formula or CKD-EPI equation should be used to estimate creatinine clearance, as serum creatinine alone may overestimate renal function in elderly patients with reduced muscle mass. Dose adjustment according to the renal impairment table above should be applied when creatinine clearance falls below 60 mL/min.

Missed Dose

If a scheduled dose of Negaban is missed, it should be administered as soon as possible. However, if the next scheduled dose is due within a few hours, the missed dose should be skipped and the regular dosing schedule resumed. Do not administer a double dose to make up for a missed dose, as this may increase the risk of adverse effects. In hospitalized patients, missed doses should be documented and the treating physician informed, as gaps in antibiotic therapy can compromise treatment efficacy and promote the development of resistance.

Overdose

Overdose with temocillin is uncommon in clinical practice because the drug is administered by healthcare professionals in controlled settings. However, if an overdose occurs (whether due to dosing errors, failure to adjust for renal impairment, or other causes), symptoms may include nausea, vomiting, diarrhea, and neurological effects such as neuromuscular hyperexcitability, myoclonus (involuntary muscle jerking), or seizures. These neurological effects are most likely to occur in patients with significantly impaired renal function who accumulate the drug. Treatment of overdose is supportive: ensure adequate hydration, monitor renal function and electrolytes, and manage seizures with benzodiazepines if they occur. Temocillin is removed by hemodialysis, which can be used to accelerate drug elimination in cases of severe overdose.

What Are the Side Effects of Negaban?

Like all medications, Negaban can cause side effects, although not everybody experiences them. Most side effects associated with temocillin are mild to moderate in severity and resolve spontaneously after treatment is completed. The side effect profile of temocillin is consistent with that of other penicillin antibiotics, with gastrointestinal disturbances and hypersensitivity reactions being the most commonly reported categories of adverse events.

The following side effect frequency grid summarizes the known adverse effects of Negaban based on clinical trial data, post-marketing surveillance, and published literature. Side effects are classified according to standard frequency categories:

The gastrointestinal side effects of Negaban (nausea, vomiting, diarrhea) are typical of penicillin antibiotics and are usually mild and self-limiting. These symptoms result from disruption of the normal intestinal microbiome by the antibiotic. Probiotics may help reduce the incidence of antibiotic-associated diarrhea, although evidence specifically for temocillin is limited. If diarrhea becomes severe or persistent, especially if it is watery, bloody, or accompanied by abdominal cramps and fever, it may indicate Clostridioides difficile infection, which requires prompt medical evaluation and specific treatment with oral vancomycin or fidaxomicin.

Injection site reactions are common with intravenous administration and typically present as pain, tenderness, swelling, or redness at the injection site. Phlebitis (inflammation of the vein) can occur with prolonged peripheral intravenous infusion and can be minimized by rotating injection sites, using an appropriate dilution volume, and administering the infusion over at least 20–30 minutes. For intramuscular administration, reconstitution with 1% lidocaine solution can help reduce injection site pain.

Hypersensitivity reactions ranging from mild skin rashes to severe anaphylaxis can occur with any penicillin antibiotic, including temocillin. Mild skin rashes (maculopapular or urticarial) typically develop several days into treatment and may resolve even with continued therapy. However, any rash should be reported to the treating physician, as it may represent the early manifestation of a more serious hypersensitivity reaction. Severe allergic reactions (anaphylaxis, angioedema, severe skin reactions) require immediate discontinuation of the drug and emergency medical treatment.

Hepatic effects, including mild transient elevations in liver enzymes (ALT, AST, alkaline phosphatase), have been reported. These are usually asymptomatic and reversible upon discontinuation of treatment. Rarely, more significant hepatic injury can occur, including cholestatic jaundice. Liver function should be monitored in patients receiving prolonged courses of treatment or in those with pre-existing liver disease.

How Should You Store Negaban?

Proper storage of Negaban is essential to maintain the stability and efficacy of the medication. The following storage guidelines apply to the different stages of the product:

Unopened vials: Store at or below 25°C (77°F). Do not freeze. Keep the vials in the original outer carton to protect from light. The shelf life of unopened vials is typically 3 years from the date of manufacture when stored under the recommended conditions. Always check the expiry date on the packaging before use and do not use the product after the expiry date.

Reconstituted solution (not further diluted): The reconstituted solution should be used immediately after preparation. If immediate use is not possible, it may be stored for up to 24 hours at 2–8°C (36–46°F) in a refrigerator. Chemical and physical in-use stability has been demonstrated for 24 hours at 2–8°C. However, from a microbiological point of view, the product should be used immediately. If not used immediately, in-use storage times and conditions are the responsibility of the user.

Diluted infusion solution: Once diluted in a compatible infusion fluid (0.9% Sodium Chloride or 5% Glucose), the solution should be used within 24 hours when stored at 2–8°C. At room temperature (25°C), the diluted solution should be used within 8 hours. Do not freeze the reconstituted or diluted solution. The solution should be visually inspected before administration. Do not use if the solution is cloudy, discolored, or contains visible particulate matter.

Disposal: Do not throw away any medicines via wastewater or household waste. Any unused product or waste material should be disposed of in accordance with local hospital protocols for pharmaceutical waste. This is important for environmental protection. In healthcare settings, unused antibiotics should be returned to the pharmacy for proper disposal.

What Does Negaban Contain?

Negaban is a simple pharmaceutical formulation consisting of the active ingredient only, with no additional excipients, preservatives, or inactive ingredients:

• Active ingredient: Temocillin 1 g (equivalent to approximately 1.05 g of temocillin sodium). Temocillin is the international nonproprietary name (INN) for 6-alpha-methoxy ticarcillin, a semi-synthetic penicillin antibiotic derived from the penicillin nucleus (6-aminopenicillanic acid).
• Sodium content: Each 1 g vial contains approximately 4.4 mmol (approximately 101 mg) of sodium, contributed by the temocillin sodium salt form. At the maximum recommended daily dose of 4 g (2 g every 12 hours), this equates to approximately 404 mg of sodium per day. This sodium content should be considered for patients on sodium-restricted diets, particularly those with heart failure, liver cirrhosis with ascites, or hypertension.

Appearance: Negaban is a white to off-white powder for solution for injection or infusion. After reconstitution with Water for Injections or 0.9% Sodium Chloride, it forms a clear to slightly opalescent, colorless to pale yellow solution. The reconstituted solution should be clear and free of visible particles. Do not use the solution if it appears cloudy, discolored, or contains particulate matter.

Pharmaceutical form: Negaban is supplied as a powder for solution for injection or infusion in clear glass vials sealed with a rubber stopper and aluminum overseal. Each vial contains temocillin 1 g. The product is available in cartons containing 1, 5, or 10 vials, depending on the market and packaging configuration. Not all pack sizes may be marketed in every country.

Chemical properties: Temocillin sodium is freely soluble in water. The molecular formula of temocillin is C₁₆H₁₆N₂O₇S₂, with a molecular weight of approximately 414.4 g/mol (free acid form). The sodium salt form has a molecular weight of approximately 436.4 g/mol. The pH of the reconstituted solution is approximately 6.5–7.5.