Cefotaxim Hameln
Cefotaxime sodium — Third-generation cephalosporin antibiotic
Quick Facts About Cefotaxim Hameln
Key Takeaways
- Broad-spectrum hospital antibiotic: Cefotaxime is a third-generation cephalosporin effective against a wide range of Gram-positive and Gram-negative bacteria, including many resistant strains
- First-line for bacterial meningitis: Excellent cerebrospinal fluid penetration when meninges are inflamed makes it a preferred choice for treating central nervous system infections
- Given by injection only: Available as a powder for reconstitution, administered via intramuscular or intravenous injection/infusion by healthcare professionals in hospital settings
- Allergy warning: Do not use if you have a known severe allergy to cephalosporins or penicillins; cross-reactivity between beta-lactam antibiotics is possible
- WHO Essential Medicine: Listed on the WHO Model List of Essential Medicines, confirming its importance in global healthcare for treating life-threatening infections
What Is Cefotaxim Hameln and What Is It Used For?
Cefotaxim hameln is a third-generation cephalosporin antibiotic containing cefotaxime sodium. It is used to treat serious bacterial infections including meningitis, septicaemia, pneumonia, urinary tract infections, bone and joint infections, and intra-abdominal infections. It works by inhibiting bacterial cell wall synthesis, leading to bacterial cell death.
Cefotaxime belongs to the cephalosporin family of antibiotics, which are structurally related to penicillins. As a third-generation cephalosporin, it offers enhanced activity against Gram-negative bacteria compared to earlier generations while retaining meaningful activity against Gram-positive organisms. The drug was first introduced in the 1980s and has become one of the most widely used parenteral antibiotics worldwide.
The active metabolite of cefotaxime, desacetylcefotaxime, also possesses antibacterial activity and works synergistically with the parent compound. This dual mechanism contributes to cefotaxime's broad spectrum of antimicrobial activity and its effectiveness against organisms that might be resistant to other cephalosporins.
Cefotaxime is particularly valued for its excellent penetration into the cerebrospinal fluid (CSF) when the meninges are inflamed. This property makes it a cornerstone in the treatment of bacterial meningitis, especially in neonates and young children where it is often preferred over ceftriaxone due to a more favourable safety profile regarding bilirubin displacement.
Approved Clinical Indications
Cefotaxime is approved for the treatment of the following infections caused by susceptible organisms:
- Bacterial meningitis: Including infections caused by Neisseria meningitidis, Streptococcus pneumoniae, Haemophilus influenzae, and Escherichia coli (particularly in neonates)
- Septicaemia / bacteraemia: Bloodstream infections caused by susceptible Gram-negative and Gram-positive organisms
- Lower respiratory tract infections: Including community-acquired pneumonia, hospital-acquired pneumonia, and lung abscess
- Urinary tract infections: Complicated pyelonephritis and other serious urinary infections
- Bone and joint infections: Osteomyelitis and septic arthritis
- Intra-abdominal infections: Peritonitis and biliary tract infections (often combined with metronidazole for anaerobic cover)
- Skin and soft tissue infections: Complicated cellulitis, wound infections, and surgical site infections
- Gonorrhoea: Uncomplicated gonococcal infections
- Surgical prophylaxis: Prevention of postoperative infections in contaminated or potentially contaminated procedures
Mechanism of Action
Cefotaxime exerts its bactericidal effect by binding to penicillin-binding proteins (PBPs) located on the inner membrane of bacterial cells. These PBPs are essential enzymes involved in the final stages of peptidoglycan cross-linking during cell wall synthesis. By inhibiting PBPs, cefotaxime disrupts the structural integrity of the bacterial cell wall, leading to osmotic instability and ultimately cell lysis and death.
The drug is resistant to hydrolysis by many beta-lactamases produced by Gram-negative bacteria, which accounts for its expanded spectrum of activity compared to first- and second-generation cephalosporins. However, it remains susceptible to extended-spectrum beta-lactamases (ESBLs) and AmpC beta-lactamases, which are increasingly encountered in hospital settings.
Cefotaxime is active against a broad range of pathogens including Streptococcus pneumoniae, Neisseria meningitidis, Haemophilus influenzae, Escherichia coli, Klebsiella species, Proteus mirabilis, Salmonella, and Shigella species. It has limited activity against Pseudomonas aeruginosa, Enterococcus species, and methicillin-resistant Staphylococcus aureus (MRSA). Local antibiograms and EUCAST/CLSI breakpoints should guide clinical decisions.
What Should You Know Before Taking Cefotaxim Hameln?
Before receiving cefotaxime, inform your doctor about all allergies (especially to antibiotics), kidney or liver problems, gastrointestinal disease history, pregnancy or breastfeeding status, and all other medications you are taking. Cefotaxime must not be used if you have a known severe allergy to cephalosporin antibiotics.
Contraindications
Cefotaxime is contraindicated in the following situations:
- Known hypersensitivity: Patients with a history of severe allergic reactions (anaphylaxis, severe skin reactions) to cefotaxime, any other cephalosporin, or to any of the excipients in the formulation
- Severe penicillin allergy: Patients who have experienced immediate-type (IgE-mediated) hypersensitivity reactions to penicillins should generally not receive cephalosporins due to the risk of cross-reactivity, although this risk is now estimated to be lower (1–2%) than previously thought
- Lidocaine allergy (for IM injection): When cefotaxime powder is reconstituted with lidocaine for intramuscular injection, it must not be given to patients with known lidocaine hypersensitivity
Warnings and Precautions
Healthcare providers should exercise caution and monitor patients closely when administering cefotaxime in the following circumstances:
- Allergic reactions: As with all beta-lactam antibiotics, serious and occasionally fatal hypersensitivity reactions have been reported. Patients should be observed carefully for at least 30 minutes after the first dose. Emergency equipment and medications (epinephrine, corticosteroids, antihistamines) must be readily available
- Clostridioides difficile-associated diarrhoea (CDAD): Antibiotic-associated colitis, including pseudomembranous colitis, has been reported with nearly all antibacterial agents, including cefotaxime. The severity can range from mild diarrhoea to fatal colitis. Treatment with cefotaxime should be discontinued if CDAD is suspected or confirmed
- Renal impairment: Dose adjustments are required in patients with significantly reduced kidney function (creatinine clearance <10 mL/min). Accumulation of the drug and its active metabolite can occur, increasing the risk of adverse effects including neurotoxicity
- Hepatic impairment: No specific dose adjustment is required, but liver function should be monitored during prolonged treatment as transient elevations in liver enzymes have been reported
- Superinfection: Prolonged use may result in overgrowth of non-susceptible organisms, including fungi. Regular assessment and appropriate measures should be taken if superinfection occurs
- Haematological monitoring: Blood counts should be monitored during prolonged treatment (>10 days), as neutropenia, leucopenia, and rarely agranulocytosis have been reported
- Sodium content: Each gram of cefotaxime sodium contains approximately 2.09 mmol (48.2 mg) of sodium. This should be considered for patients on sodium-restricted diets or those with heart failure
Seek immediate medical attention if you develop signs of a severe allergic reaction: difficulty breathing, swelling of the face, lips, tongue or throat, severe skin rash, or a sudden drop in blood pressure. Severe allergic reactions to cephalosporins, although rare, can be life-threatening and require emergency treatment.
Pregnancy and Breastfeeding
Cefotaxime crosses the placental barrier, and concentrations of the drug can be measured in foetal blood and amniotic fluid. Animal reproduction studies have not demonstrated teratogenic effects. However, there are no adequate and well-controlled studies in pregnant women. The drug should only be used during pregnancy if the potential benefit justifies the potential risk to the foetus. According to the European Medicines Agency (EMA), cephalosporins are generally considered acceptable for use in pregnancy when clinically indicated.
Cefotaxime is excreted in breast milk in low concentrations (approximately 0.3 µg/mL after a 1 g dose). While this is unlikely to cause direct toxicity to the nursing infant, it may lead to sensitisation or disruption of the infant's gut flora. A decision should be made whether to discontinue breastfeeding or discontinue the drug, taking into account the importance of the drug to the mother.
How Does Cefotaxim Hameln Interact with Other Drugs?
Cefotaxime can interact with several medications including probenecid (which increases cefotaxime levels), aminoglycosides (increased nephrotoxicity risk), loop diuretics (increased nephrotoxicity risk), and anticoagulants like warfarin (enhanced anticoagulant effect). Always inform your healthcare team about all medications you are taking.
Drug interactions with cefotaxime are clinically significant in several contexts. Healthcare professionals must carefully evaluate the patient's medication list before initiating cefotaxime therapy. The following table summarises the most important known interactions:
Major Interactions
| Interacting Drug | Effect | Severity | Clinical Recommendation |
|---|---|---|---|
| Probenecid | Inhibits renal tubular secretion of cefotaxime, increasing plasma concentrations and prolonging half-life | Major | Dose adjustment may be necessary; monitor for increased adverse effects |
| Aminoglycosides (gentamicin, tobramycin, amikacin) | Synergistic antibacterial activity but additive nephrotoxicity risk | Major | Monitor renal function closely; administer separately (do not mix in same infusion); stagger administration times |
| Loop diuretics (furosemide, bumetanide) | Increased risk of nephrotoxicity through additive renal tubular damage | Moderate | Monitor renal function and electrolytes; ensure adequate hydration |
| Warfarin and other vitamin K antagonists | Possible enhancement of anticoagulant effect; cephalosporins may interfere with vitamin K synthesis by suppressing gut flora | Moderate | Monitor INR closely; adjust warfarin dose as needed |
| Oral contraceptives | Potential reduction in contraceptive efficacy through disruption of enterohepatic recirculation of oestrogen | Minor | Use additional barrier contraception during and for 7 days after antibiotic course |
| Methotrexate | Reduced renal clearance of methotrexate, potentially increasing methotrexate toxicity | Major | Monitor methotrexate levels; assess renal function; may need methotrexate dose adjustment |
Minor Interactions
In addition to the major interactions listed above, cefotaxime may cause false-positive results in certain laboratory tests:
- Urine glucose tests: Non-enzymatic (copper reduction) methods such as Benedict's solution or Clinitest may yield false-positive results. Glucose oxidase-based methods (e.g., Clinistix) are unaffected and should be used instead
- Direct Coombs test: Cephalosporins can cause a positive direct antiglobulin (Coombs) test, which may interfere with cross-matching of blood. This does not usually indicate haemolytic anaemia but should be noted for transfusion purposes
- Creatinine assays: High concentrations of cefotaxime may interfere with the Jaffé reaction used to measure serum creatinine, potentially leading to falsely elevated readings
Cefotaxime should not be mixed in the same syringe or infusion bag with aminoglycosides, vancomycin, or alkaline solutions (including sodium bicarbonate). When combination therapy with aminoglycosides is required, the drugs should be administered at separate sites or at staggered intervals, and the IV line should be flushed between infusions.
What Is the Correct Dosage of Cefotaxim Hameln?
Cefotaxime dosage depends on the type and severity of infection, the patient's age, weight, and renal function. Adults typically receive 1–2 g every 8–12 hours by IV or IM injection. For severe infections such as meningitis, doses up to 12 g per day may be required. Doses are always determined and administered by a healthcare professional.
Cefotaxim hameln is supplied as a powder that must be reconstituted before administration. It can be given by intramuscular (IM) injection, intravenous (IV) bolus injection (over 3–5 minutes), or intravenous infusion (over 20–60 minutes). The choice of route and dose depends on the clinical situation. All doses listed below follow current international guidelines and the approved Summary of Product Characteristics (SmPC).
Adults
| Indication | Dose | Frequency | Maximum Daily Dose |
|---|---|---|---|
| Uncomplicated infections | 1 g | Every 12 hours | 2 g |
| Moderate infections | 1–2 g | Every 8 hours | 6 g |
| Severe / life-threatening infections | 2 g | Every 6–8 hours | 12 g |
| Bacterial meningitis | 2 g | Every 6 hours | 12 g |
| Uncomplicated gonorrhoea | 500 mg | Single dose (IM) | 500 mg |
| Surgical prophylaxis | 1 g | 30–60 min before incision | 1–2 g |
Children
Dosing in children is based on body weight and the severity of infection. Cefotaxime is one of the few third-generation cephalosporins that can be safely used in neonates, including premature infants.
Neonates (0–28 days)
- Age 0–7 days: 50 mg/kg every 12 hours (IV)
- Age 8–28 days: 50 mg/kg every 8 hours (IV)
- Meningitis: 50 mg/kg every 6–8 hours (IV)
Infants and Children (1 month – 12 years)
- Standard infections: 100–150 mg/kg/day divided into 3–4 doses
- Severe infections / meningitis: 200 mg/kg/day divided into 4 doses (maximum 12 g/day)
- Body weight ≥50 kg: Use adult dosing
Adolescents (≥12 years)
- Use adult dosing regimens
Elderly
In elderly patients with normal renal function, no dose adjustment is required. However, elderly patients frequently have reduced renal function, and dose adjustments should be based on measured or estimated creatinine clearance. Renal function should be monitored regularly in elderly patients receiving cefotaxime, especially during prolonged courses.
Dose Adjustment in Renal Impairment
In patients with significantly impaired renal function (creatinine clearance <10 mL/min), the maintenance dose should be halved while maintaining the same dosing interval. No adjustment is needed for creatinine clearance >10 mL/min. In patients on haemodialysis, a supplementary dose should be given at the end of each dialysis session, as cefotaxime and its active metabolite are partially removed by haemodialysis.
Missed Dose
Since cefotaxime is administered in hospital settings by healthcare professionals, missed doses are uncommon. If a dose is missed, it should be given as soon as possible, and the subsequent dose should be rescheduled to maintain the prescribed dosing interval. Do not give a double dose to compensate for a missed dose.
Overdose
Overdose with cefotaxime may lead to neurotoxic symptoms including encephalopathy (confusion, altered consciousness), seizures, and myoclonus, particularly in patients with impaired renal function. There is no specific antidote. Treatment is supportive and symptomatic. In severe overdose, haemodialysis may be considered to enhance elimination, although evidence for its efficacy is limited. Maintain airway, breathing, and circulation, and monitor neurological status, renal function, and electrolytes closely.
What Are the Side Effects of Cefotaxim Hameln?
Like all antibiotics, cefotaxime can cause side effects. The most common include injection site reactions, diarrhoea, nausea, and skin rash. Uncommon but serious side effects include severe allergic reactions (anaphylaxis), Clostridioides difficile-associated diarrhoea, and blood disorders. Most side effects are mild and resolve after treatment is completed.
The following side effects have been reported during clinical trials and post-marketing surveillance. Side effects are categorised by frequency according to the standard MedDRA classification. Not everyone experiences side effects, and most people tolerate cefotaxime well. If you experience any unusual symptoms during or after treatment, inform your healthcare team promptly.
Very Common (>1 in 10)
- Pain at injection site
- Induration (hardness) at injection site after IM injection
Common (1 in 10 to 1 in 100)
- Diarrhoea
- Nausea and vomiting
- Skin rash (maculopapular or urticarial)
- Pruritus (itching)
- Phlebitis or thrombophlebitis at IV injection site
- Transient elevation of liver enzymes (AST, ALT, alkaline phosphatase)
- Transient leucopenia, eosinophilia
Uncommon (1 in 100 to 1 in 1,000)
- Abdominal pain
- Fever (drug fever)
- Headache
- Transient increase in serum creatinine and blood urea nitrogen
- Neutropenia, thrombocytopenia
- Candidal superinfection (oral thrush, vaginal candidiasis)
Rare (<1 in 1,000)
- Anaphylaxis and severe allergic reactions
- Clostridioides difficile-associated diarrhoea (pseudomembranous colitis)
- Stevens-Johnson syndrome, toxic epidermal necrolysis
- Erythema multiforme
- Agranulocytosis, haemolytic anaemia
- Seizures (particularly with high doses in renal impairment)
- Encephalopathy
- Interstitial nephritis
- Cardiac arrhythmias (with rapid IV bolus injection)
- Jarisch-Herxheimer reaction (when treating spirochaetal infections)
Contact your healthcare provider or seek emergency care immediately if you develop: severe watery or bloody diarrhoea (even weeks after stopping the antibiotic), signs of allergic reaction (difficulty breathing, facial swelling, severe skin rash), unusual bleeding or bruising, yellowing of the skin or eyes, seizures or confusion, or if symptoms worsen despite treatment.
Long-term or repeated use of cefotaxime, as with other broad-spectrum antibiotics, may promote the selection of resistant bacteria or fungal overgrowth. Healthcare providers should follow antimicrobial stewardship principles, using the narrowest effective spectrum for the shortest effective duration.
How Should You Store Cefotaxim Hameln?
Store unopened vials below 25°C, protected from light. Do not freeze. After reconstitution, the solution should be used immediately or within 24 hours if stored in a refrigerator (2–8°C). Discard any unused solution. Keep out of the reach and sight of children.
Cefotaxim hameln is supplied as a sterile powder in glass vials. The powder should be stored in its original packaging to protect from light. The shelf life of the unopened product is typically 2–3 years from the date of manufacture, as indicated on the packaging. Do not use this medicine after the expiry date printed on the carton and vial label.
Once reconstituted, the solution should be inspected visually for particulate matter and discolouration prior to administration. Solutions that appear cloudy, contain particles, or have changed colour should not be used. Freshly prepared solutions may range from pale yellow to amber in colour; this variation does not indicate a loss of potency.
Chemical and physical in-use stability has been demonstrated for up to 24 hours at 2–8°C and for up to 6 hours at 25°C after reconstitution. From a microbiological point of view, the reconstituted solution should be used immediately. If not used immediately, in-use storage times and conditions prior to use are the responsibility of the user and would normally not exceed 24 hours at 2–8°C.
Do not dispose of medicines via wastewater or household waste. In hospital settings, unused medicines are disposed of through designated pharmaceutical waste systems in accordance with local regulations.
What Does Cefotaxim Hameln Contain?
Each vial of Cefotaxim hameln 1 g contains cefotaxime sodium equivalent to 1 g of cefotaxime as the active substance. It contains no other excipients. Each gram of cefotaxime sodium provides approximately 2.09 mmol (48.2 mg) of sodium.
Cefotaxim hameln is a minimally formulated product containing only the active ingredient cefotaxime sodium as a sterile powder. There are no preservatives, stabilisers, or other excipients in the formulation. This simple composition reduces the risk of excipient-related adverse reactions and makes the product suitable for patients with sensitivities to common pharmaceutical additives.
Active Ingredient
- Cefotaxime sodium: A semi-synthetic, broad-spectrum, third-generation cephalosporin antibiotic. Each vial contains cefotaxime sodium equivalent to 1,000 mg (1 g) of cefotaxime free acid. The molecular formula is C16H16N5NaO7S2, with a molecular weight of approximately 477.4 g/mol
Reconstitution Solvents
The powder must be reconstituted prior to use with an appropriate solvent. Recommended solvents include:
- For IV injection: Water for injections (4 mL per 1 g vial)
- For IV infusion: 0.9% sodium chloride solution or 5% glucose solution (50–100 mL)
- For IM injection: Water for injections (4 mL per 1 g vial) or 1% lidocaine hydrochloride solution (to reduce injection pain)
Each gram of cefotaxime sodium contains approximately 2.09 mmol (48.2 mg) of sodium. This should be taken into consideration by patients on a controlled sodium diet. For patients receiving high doses (e.g., 12 g/day for meningitis), the total daily sodium load from cefotaxime alone would be approximately 578 mg, which is clinically significant for patients with heart failure or renal impairment.
Physical Properties
Cefotaxime sodium powder is white to pale yellow in colour. When reconstituted, the solution is clear and may range from pale yellow to amber. The pH of the reconstituted solution is between 5.0 and 7.5. The product is supplied in Type I or Type III clear glass vials with rubber stoppers and aluminium flip-off caps.
Frequently Asked Questions About Cefotaxim Hameln
Cefotaxime is a third-generation cephalosporin antibiotic used to treat serious bacterial infections. Its primary uses include bacterial meningitis, septicaemia (bloodstream infections), pneumonia, complicated urinary tract infections, bone and joint infections, intra-abdominal infections, and gonorrhoea. It is also used for surgical prophylaxis to prevent infections after certain types of surgery. Cefotaxime is always administered in hospital settings by healthcare professionals via injection or infusion.
Cefotaxime crosses the placenta, but animal studies have not shown teratogenic effects. It is classified as FDA pregnancy category B, meaning animal studies show no risk but there are no adequate studies in humans. It should only be used during pregnancy when clearly needed and when the expected benefit outweighs the potential risk. Cephalosporins as a class are generally considered among the safer antibiotic options during pregnancy. Your doctor will evaluate the risk-benefit balance for your specific clinical situation.
The most frequently reported side effects are injection site reactions (pain, swelling, redness, and hardness), particularly after intramuscular injection. Other common side effects include diarrhoea, nausea, vomiting, skin rash, itching, and transient elevation of liver enzymes. Phlebitis (inflammation of the vein) may occur at the IV injection site. Most side effects are mild and resolve spontaneously after treatment ends. Serious side effects such as severe allergic reactions, C. difficile colitis, and blood disorders are rare but require immediate medical attention.
There is a small risk of cross-reactivity between penicillins and cephalosporins, now estimated at approximately 1–2% with modern third-generation cephalosporins like cefotaxime. Patients with a history of mild penicillin allergy (e.g., non-severe rash) may receive cefotaxime with careful monitoring. However, patients who have experienced severe penicillin allergic reactions (anaphylaxis, angioedema, severe urticaria) should generally avoid cephalosporins unless allergy testing confirms safety. Always inform your healthcare team about all drug allergies before receiving any antibiotic.
Both cefotaxime and ceftriaxone are third-generation cephalosporins with broadly similar antimicrobial spectra. Key differences include: (1) Half-life — ceftriaxone has a much longer half-life (6–9 hours) compared to cefotaxime (approximately 1 hour), allowing once-daily dosing for ceftriaxone versus multiple daily doses for cefotaxime. (2) Neonatal use — cefotaxime is preferred in neonates because ceftriaxone can displace bilirubin from albumin, potentially worsening neonatal jaundice. (3) Biliary disease — cefotaxime is preferred in patients with gallbladder or biliary tract disease since ceftriaxone can cause biliary sludge and pseudolithiasis. (4) Elimination — cefotaxime is primarily renally excreted while ceftriaxone undergoes significant biliary excretion.
Treatment duration varies depending on the type and severity of infection. Uncomplicated infections typically require 5–7 days of treatment. Bacterial meningitis usually requires 10–14 days (or up to 21 days for Gram-negative meningitis). Bone and joint infections may require 4–6 weeks. Surgical prophylaxis is usually a single dose or a short course of 24 hours. Your doctor will determine the appropriate treatment duration based on clinical response, infection severity, and causative organism. Do not stop treatment early even if you feel better, as this can contribute to antibiotic resistance.
References
- World Health Organization (WHO). WHO Model List of Essential Medicines – 23rd List (2023). Geneva: WHO; 2023. Available at: who.int/publications
- European Medicines Agency (EMA). Cefotaxime – Summary of Product Characteristics. Amsterdam: EMA. Available at: ema.europa.eu
- Joint Formulary Committee. British National Formulary (BNF) 86. London: BMJ Group and Pharmaceutical Press; 2023. Cefotaxime monograph.
- Mandell GL, Bennett JE, Dolin R. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 9th ed. Philadelphia: Elsevier; 2020. Chapter 20: Cephalosporins.
- European Committee on Antimicrobial Susceptibility Testing (EUCAST). Clinical Breakpoints – Breakpoints and Guidance. Version 14.0, 2024. Available at: eucast.org
- Pichichero ME. A review of evidence supporting the American Academy of Pediatrics recommendation for prescribing cephalosporin antibiotics for penicillin-allergic patients. Pediatrics. 2005;115(4):1048–1057. doi:10.1542/peds.2004-1276
- van de Beek D, Cabellos C,"; et al. ESCMID guideline: diagnosis and treatment of acute bacterial meningitis. Clin Microbiol Infect. 2016;22 Suppl 3:S37–S62. doi:10.1016/j.cmi.2016.01.007
- Solomkin JS, Mazuski JE, Bradley JS, et al. Diagnosis and management of complicated intra-abdominal infection in adults and children: guidelines by the Surgical Infection Society and the Infectious Diseases Society of America. Clin Infect Dis. 2010;50(2):133–164.
About the Medical Editorial Team
This article was written and reviewed by the iMedic Medical Editorial Team, comprising licensed physicians specialising in infectious disease, clinical pharmacology, and hospital medicine. All content follows the GRADE evidence framework and has been peer-reviewed for accuracy and clinical relevance.
iMedic Medical Editorial Team — Specialists in infectious disease and antimicrobial therapy with extensive clinical and academic experience.
iMedic Medical Review Board — Independent panel of board-certified physicians who review all content according to WHO, EMA, and BNF guidelines.
Evidence Level: 1A — Based on systematic reviews, meta-analyses, and international clinical guidelines (WHO Essential Medicines List, EUCAST breakpoints, BNF recommendations).
Conflict of Interest: None. iMedic receives no pharmaceutical company funding. All editorial content is independently produced.