Ampitar (Ampicillin): Uses, Dosage & Side Effects
An injectable penicillin antibiotic used to treat serious bacterial infections including meningitis, pneumonia, and endocarditis
Ampitar is a parenteral (injectable) formulation of ampicillin, a broad-spectrum aminopenicillin antibiotic. It is administered by intramuscular injection, intravenous injection, or intravenous infusion for the treatment of serious bacterial infections that require rapid achievement of high blood concentrations of antibiotic. Ampitar is indicated for conditions including bacterial meningitis, severe pneumonia, upper urinary tract infections (pyelonephritis), acute exacerbation of chronic bronchitis, gastrointestinal infections, bloodstream infections (septicemia), and infective endocarditis. It is available by prescription only and is typically administered by healthcare professionals in hospital settings.
Quick Facts: Ampitar
Key Takeaways
- Ampitar is the injectable (parenteral) form of ampicillin, a broad-spectrum aminopenicillin antibiotic used in hospital settings for serious bacterial infections including meningitis, septicemia, and endocarditis.
- Do not use Ampitar if you have a known allergy to penicillin, ampicillin, or any other beta-lactam antibiotic (including cephalosporins), as severe allergic reactions including potentially fatal anaphylaxis can occur.
- Ampitar contains a significant amount of sodium (up to 842.4 mg at maximum daily doses), which is an important consideration for patients on sodium-restricted diets or those with heart failure or kidney disease.
- Common side effects include diarrhea and skin rash; more serious but less common effects include anaphylaxis, severe reduction in white blood cells (agranulocytosis), and Clostridioides difficile-associated colitis.
- Dose adjustment is required in patients with significantly impaired kidney function (creatinine clearance below 30 ml/min) to prevent drug accumulation and toxicity.
What Is Ampitar and What Is It Used For?
Ampitar contains the active substance ampicillin (supplied as ampicillin sodium), which belongs to the aminopenicillin subclass of penicillin antibiotics. First developed in the early 1960s, ampicillin was one of the earliest broad-spectrum penicillins, extending the antibacterial range of the original penicillins to include certain Gram-negative bacteria. While oral ampicillin has largely been superseded by its better-absorbed derivative amoxicillin for mild to moderate infections, parenteral ampicillin remains an essential antibiotic for the treatment of serious and life-threatening infections where rapid achievement of high tissue and blood concentrations is critical.
Ampicillin works through a bactericidal mechanism of action. It inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins (PBPs), which are enzymes essential for the cross-linking of peptidoglycan—the structural polymer that gives bacterial cell walls their rigidity and strength. When ampicillin blocks these enzymes, the bacteria are unable to maintain the integrity of their cell walls, leading to osmotic instability, cell lysis, and bacterial death. Because human cells do not possess peptidoglycan cell walls, ampicillin is selectively toxic to bacteria with relatively low toxicity to human tissues.
Ampicillin has activity against a range of both Gram-positive and Gram-negative bacteria. It is particularly effective against Streptococcus pneumoniae, Streptococcus pyogenes, Enterococcus faecalis, Listeria monocytogenes, Neisseria meningitidis, Haemophilus influenzae (non-beta-lactamase producing strains), and certain strains of Escherichia coli, Proteus mirabilis, and Salmonella species. Notably, ampicillin is one of the few penicillins with reliable activity against Enterococcus and Listeria, which makes it indispensable in the treatment of enterococcal endocarditis and Listeria meningitis.
Ampitar is specifically indicated for the treatment of the following conditions when caused by susceptible organisms:
- Bacterial meningitis: Ampicillin is a key drug for the empirical treatment of neonatal meningitis and is the drug of choice for Listeria monocytogenes meningitis in adults. It achieves adequate cerebrospinal fluid (CSF) concentrations when the meninges are inflamed.
- Pneumonia: When other penicillins are ineffective or unsuitable, intravenous ampicillin may be used to treat community-acquired or hospital-acquired pneumonia, particularly when caused by susceptible organisms.
- Upper urinary tract infection (pyelonephritis): Severe kidney infections caused by susceptible Gram-negative bacteria may be treated with parenteral ampicillin, often in combination with an aminoglycoside.
- Acute exacerbation of chronic bronchitis: Intravenous ampicillin may be used in severe acute exacerbations when oral therapy is inappropriate.
- Gastrointestinal infections: Including invasive Salmonella infections and other enteric bacterial infections requiring parenteral therapy.
- Septicemia (bloodstream infection): When associated with any of the above infections, particularly in neonates and immunocompromised patients.
- Infective endocarditis: Both for treatment (usually in combination with gentamicin for enterococcal endocarditis) and for prophylaxis before certain dental or surgical procedures in high-risk patients.
Ampicillin is included on the World Health Organization (WHO) Model List of Essential Medicines, reflecting its critical importance in global healthcare. Under the WHO AWaRe (Access, Watch, Reserve) classification system, ampicillin is classified as an Access antibiotic, meaning it should be widely available and used as a first-line option for common and serious infections. Ampitar is supplied as a white to pale yellow powder that must be reconstituted into a solution immediately before use. It is available in 1 g and 2 g vials and is approved for use across the European Economic Area.
Unlike oral ampicillin, which has relatively low and variable oral bioavailability (approximately 40–50%), intravenous administration of Ampitar achieves 100% bioavailability and much higher peak plasma concentrations. This is why the parenteral route is preferred for serious and life-threatening infections where rapid achievement of bactericidal drug levels is essential. For milder infections where oral therapy is appropriate, amoxicillin (a structurally related aminopenicillin with superior oral absorption) is generally preferred.
What Should You Know Before Using Ampitar?
Before treatment with Ampitar begins, it is essential that your healthcare team has a complete picture of your medical history, current medications, and any known allergies. Because ampicillin is a beta-lactam antibiotic, the most important safety consideration is the risk of allergic reactions, which can range from mild skin rashes to severe, life-threatening anaphylaxis. Your doctor will carefully weigh the benefits of treatment against these potential risks before prescribing Ampitar.
Contraindications
Ampitar must not be used in the following circumstances:
- Known allergy to ampicillin: If you have previously experienced an allergic reaction to ampicillin, you must not receive this medication again.
- Known allergy to other beta-lactam antibiotics: This includes other penicillins (such as amoxicillin, benzylpenicillin, flucloxacillin) and cephalosporins (such as cefalexin, ceftriaxone). Cross-reactivity between these antibiotic classes can occur due to their shared beta-lactam ring structure.
- Known allergy to any excipient: While Ampitar contains only ampicillin sodium with no additional excipients, the sodium content itself may be relevant for certain patients.
Warnings and Precautions
Speak to your doctor before receiving Ampitar if any of the following apply to you:
- History of any allergic reaction to any antibiotic: Hypersensitivity reactions to ampicillin may develop more readily in individuals with a general tendency toward allergic reactions. These reactions can manifest in various ways and with varying severity, ranging from skin changes to anaphylactic shock.
- History of allergy to cephalosporins: Although the true cross-reactivity rate between penicillins and cephalosporins is lower than historically believed (estimated at 1–2%), caution is warranted if you have experienced a hypersensitivity reaction to any cephalosporin antibiotic.
- Kidney impairment: If you have been diagnosed with kidney disease or reduced kidney function, your doctor will need to adjust your dose of Ampitar. In patients with severely impaired kidney function (creatinine clearance below 30 ml/min), the dose must be reduced to prevent accumulation of the drug and potential toxicity.
- History of gastrointestinal disease: Particularly if you have a history of colitis (inflammation of the colon), you may be at increased risk of developing antibiotic-associated colitis, including Clostridioides difficile infection.
If you develop symptoms of watery diarrhea (often with blood and mucus), abdominal pain, and/or fever during or after treatment with Ampitar, contact your doctor immediately. These may be symptoms of pseudomembranous colitis (Clostridioides difficile-associated diarrhea), a potentially serious complication of antibiotic treatment that requires prompt medical management.
Pregnancy and Breastfeeding
If you are pregnant, breastfeeding, think you may be pregnant, or are planning to have a baby, discuss this with your doctor before receiving Ampitar.
Pregnancy: Ampicillin can be used during pregnancy when the physician considers it medically necessary. Ampicillin crosses the placental barrier, but extensive clinical experience over many decades has not demonstrated teratogenic effects, and penicillins are generally considered among the safest antibiotics to use during pregnancy. Nevertheless, the decision to use Ampitar during pregnancy should always be based on a careful assessment of the potential benefits and risks by the treating physician.
Breastfeeding: Ampicillin is excreted in breast milk in small quantities. While the amounts passed to the nursing infant are generally small, there is a theoretical risk that the infant could develop hypersensitivity reactions, diarrhea, or mucosal fungal infections (thrush). In some cases, this may necessitate discontinuation of breastfeeding. Discuss the risks and benefits with your doctor.
Fertility: In animal studies, ampicillin had no effect on fertility. No human fertility data specific to ampicillin are available, but clinical experience has not raised concerns about adverse effects on fertility.
Effect on Urine Tests
Patients receiving ampicillin may obtain false-positive results on certain urine glucose tests (those based on copper reduction methods, such as Benedict’s or Fehling’s reagent or Clinitest tablets). If glucose monitoring is necessary during treatment, enzymatic glucose tests (such as glucose oxidase-based methods) should be used instead. Inform your doctor or nurse that you are receiving Ampitar if any urine testing is planned.
Sodium Content
Ampitar contains a clinically significant amount of sodium, which is an important consideration for patients on sodium-restricted diets or those with conditions such as heart failure, kidney disease, or hypertension.
- Ampitar 1 g: Contains 70.2 mg sodium per vial (3.51% of the WHO recommended maximum daily sodium intake for adults of 2 g).
- Ampitar 2 g: Contains 140.4 mg sodium per vial (7.02% of the WHO recommended maximum daily sodium intake).
- Maximum daily dose: At the highest recommended daily doses, the sodium content can reach 842.4 mg (42.1% of the WHO recommended maximum daily sodium intake).
If Ampitar is reconstituted or diluted with isotonic sodium chloride solution (0.9% saline), the additional sodium from the diluent must also be taken into account. Consult your pharmacist or doctor if you need to receive Ampitar daily over an extended period, especially if you have been advised to follow a low-sodium diet.
Driving and Operating Machinery
Ampitar has no or negligible effect on the ability to drive vehicles or operate machinery. However, driving or operating machinery is not recommended if you experience side effects that impair your concentration, such as drowsiness. You are personally responsible for assessing whether you are fit to drive or perform tasks requiring alertness.
How Does Ampitar Interact with Other Drugs?
Drug interactions can alter how a medication works, increase the risk of side effects, or reduce therapeutic effectiveness. Tell your doctor, pharmacist, or nurse about all medications you are currently taking, have recently taken, or might take, including over-the-counter medicines and herbal supplements. The following are the most clinically important interactions with ampicillin.
Significant Interactions
| Interacting Drug | Effect | Clinical Significance |
|---|---|---|
| Allopurinol | Significantly increased risk of allergic skin rash when taken concurrently with ampicillin | High – Avoid combination if possible; monitor closely for skin reactions |
| Methotrexate | Ampicillin can reduce the renal excretion of methotrexate, leading to increased methotrexate blood levels and toxicity | High – Monitor methotrexate levels and adjust dose as needed; watch for signs of toxicity |
| Probenecid | Inhibits renal tubular secretion of ampicillin, increasing and prolonging ampicillin blood levels | Moderate – Sometimes used intentionally to boost ampicillin levels; dose adjustment may be needed |
| Warfarin / oral anticoagulants | Ampicillin may enhance the anticoagulant effect by disrupting vitamin K-producing gut flora | Moderate – Monitor INR closely during and after ampicillin treatment |
| Oral contraceptives | Theoretical reduction in effectiveness of combined hormonal contraceptives through disruption of enterohepatic recycling of estrogens | Low to Moderate – Use additional barrier contraception during treatment and for 7 days afterward if vomiting or diarrhea occurs |
| Aminoglycosides | Synergistic bactericidal effect but physical incompatibility in the same IV line; ampicillin may inactivate aminoglycosides if mixed | Moderate – Administer separately; do not mix in the same IV solution |
Additional Considerations
Bacteriostatic antibiotics: Theoretically, bacteriostatic antibiotics (such as tetracyclines, macrolides, and chloramphenicol) may antagonize the bactericidal action of ampicillin, since ampicillin requires actively dividing bacteria to exert its effect. Concurrent use should generally be avoided unless specifically recommended by a specialist.
IV compatibility: Substances for which compatibility studies are lacking should not be added to ampicillin solutions. Ampicillin solutions should be reconstituted and administered strictly according to the manufacturer’s instructions to avoid degradation or precipitation of the drug.
What Is the Correct Dosage of Ampitar?
Ampitar is always administered by healthcare professionals in a clinical setting. You will receive it as an injection into a muscle (intramuscular), a slow injection into a vein (intravenous bolus), or a drip into a vein (intravenous infusion). Your doctor will determine the appropriate dose, route of administration, and duration of treatment based on the type, location, and severity of your infection, as well as your kidney function and body weight.
Adults
Intramuscular Injection
500 mg four times daily (every 6 hours). Reconstitute 1 g in 4 ml water for injection.
Intravenous Injection
500 mg to 2 g four to six times daily. The 2 g dose should be injected slowly over at least 3–4 minutes. Higher doses may be given intravenously when clinically necessary.
Intermittent Intravenous Infusion
2 g four to six times daily, diluted in 100 ml of 0.9% sodium chloride solution and infused over 15–30 minutes. Solutions should be prepared in polyolefin containers.
Continuous Intravenous Infusion
6–12 g per day administered via continuous drip. An infusion pump should be used whenever possible. Each 2 g is reconstituted in 15 ml water for injection, then added to 500 ml of 0.9% sodium chloride solution.
Endocarditis Prophylaxis
A single 2 g intravenous dose administered 30–60 minutes before the procedure.
Children
| Route | Dose | Notes |
|---|---|---|
| Intramuscular | 50 mg/kg/day divided into 4 doses (every 6 hours) | Standard dose for moderate infections |
| Intravenous (severe infections) | 100–200 mg/kg/day divided into 4 doses | For serious systemic infections |
| Intravenous (bacterial meningitis) | Up to 400 mg/kg/day divided into 4 doses | Maximum dose for CNS infections |
| Neonates & premature infants (IM) | 25–50 mg/kg/day divided into 2 doses (every 12 hours) | Reduced frequency due to immature renal function |
| Endocarditis prophylaxis | 50 mg/kg IV as a single dose | Given 30–60 minutes before procedure |
Patients with Kidney Impairment
Dose adjustment is not required in patients with a creatinine clearance (CrCl) above 30 ml/min. For patients with more severe kidney impairment, the following dose reductions are recommended to prevent drug accumulation:
| Creatinine Clearance | Dose Adjustment | Maximum Dose |
|---|---|---|
| > 30 ml/min | No adjustment required | Standard dosing |
| 20–30 ml/min | Reduce to 2/3 of normal dose | 1 g every 8 hours |
| < 20 ml/min | Reduce to 1/3 of normal dose | 1 g every 8 hours |
In patients with severe renal insufficiency, a general maximum of 1 g ampicillin every 8 hours should not be exceeded. For patients on hemodialysis, ampicillin is removed by the dialysis procedure, and supplemental doses may be required after dialysis sessions.
Missed Dose
Since Ampitar is administered by healthcare professionals in a hospital or clinical setting, doses are given on a strict schedule. If you believe a dose may have been missed, inform your doctor or nurse immediately. Do not receive a double dose to compensate for a missed one. Maintaining consistent dosing intervals is important for keeping effective antibiotic levels in the bloodstream.
Overdose
Large doses of ampicillin are generally well tolerated. However, in patients with impaired kidney function or a defective blood-brain barrier, parenteral administration of very high doses can lead to toxic symptoms. Acute reactions are most commonly due to allergic (hypersensitivity) reactions rather than direct drug toxicity.
Signs and symptoms of ampicillin overdose may include:
- Nausea, vomiting, and diarrhea
- Electrolyte disturbances
- Decreased consciousness
- Involuntary muscle twitching (fasciculations) and myoclonus
- Seizures and coma
- Kidney failure
- Hemolytic reactions (destruction of red blood cells)
- Metabolic acidosis
In rare cases, an anaphylactic reaction may occur within 20–40 minutes after a large dose. Treatment of overdose is symptomatic and supportive. In severe cases, hemoperfusion or hemodialysis may be used to remove the drug from the bloodstream. Anaphylactic reactions require emergency treatment with epinephrine (adrenaline), intravenous corticosteroids, intravenous fluids, and correction of acidosis.
What Are the Side Effects of Ampitar?
Like all medicines, Ampitar can cause side effects, although not everyone experiences them. The likelihood and type of side effects can vary depending on the dose, route of administration, duration of treatment, and individual patient factors. Most side effects of ampicillin are mild and resolve after treatment is completed. However, some side effects are serious and require immediate medical attention.
Contact your doctor or go to the emergency department immediately if you experience any of the following: difficulty breathing, swelling of the face, lips, tongue, or throat (angioedema), widespread hives (urticaria), severe dizziness, or a rapid or weak pulse. These may be signs of a severe allergic reaction (anaphylaxis), which can be life-threatening and requires emergency treatment.
Common Side Effects
May affect up to 1 in 10 patients
- Diarrhea or loose stools
- Skin rash (maculopapular rash)
Uncommon Side Effects
May affect up to 1 in 100 patients
- Anemia (reduction in red blood cells) leading to pale skin, weakness, and shortness of breath
- Thrombocytopenia (reduction in blood platelets) leading to easy bruising or bleeding
- Leukopenia (decrease in white blood cells)
- Eosinophilia (increase in a type of white blood cell, often associated with allergic conditions)
- Inflammation of the tongue (glossitis) and oral mucosa (stomatitis)
- Nausea and vomiting
- Colitis (inflammation of the colon), including pseudomembranous colitis
- Diarrhea (watery, potentially with blood and mucus)
- Urticaria (hives, nettle rash)
- Agranulocytosis (severe reduction in white blood cells, impairing immune defense)
Rare Side Effects
May affect up to 1 in 1,000 patients
- Anaphylaxis (severe, potentially life-threatening allergic reaction)
- Exfoliative dermatitis (severe skin inflammation with peeling)
- Erythema multiforme (a serious skin condition with target-shaped lesions)
- Candida infection (fungal overgrowth, including oral thrush and vaginal candidiasis)
Additional Side Effects
Injection site reactions: Local pain may occur at the site of intramuscular injection. With intravenous administration, phlebitis (inflammation of the vein) may occur, particularly with prolonged infusion through a peripheral line.
Elevated liver enzymes: Transient increases in liver enzyme levels (transaminases) have been reported during treatment with ampicillin. These are usually mild, asymptomatic, and resolve after discontinuation of therapy.
Jarisch-Herxheimer reaction: When ampicillin is used to treat certain infections (such as syphilis or Listeria infections), a temporary worsening of symptoms may occur as bacteria are killed and release their cellular contents. This is known as the Jarisch-Herxheimer reaction and is not an allergic reaction to the antibiotic.
If you develop persistent or severe diarrhea during or in the weeks following treatment with Ampitar, do not take anti-diarrheal medicines (such as loperamide) without consulting your doctor first. Severe antibiotic-associated diarrhea, particularly when caused by Clostridioides difficile, requires specific medical management and anti-diarrheal agents may worsen the condition.
Reporting Side Effects
Reporting suspected adverse reactions after a medicine has been authorized is important for continuous monitoring of the benefit-risk balance of the drug. Healthcare professionals and patients are encouraged to report any suspected side effects to their national pharmacovigilance authority. This helps ensure ongoing safety monitoring and can lead to updated prescribing information that benefits all patients.
How Should You Store Ampitar?
Proper storage of pharmaceutical products is essential to maintain their safety and effectiveness. Ampitar should be stored according to the following guidelines:
- Storage conditions: No special storage conditions are required for the unopened powder. Keep the product in its original packaging to protect it from light and moisture.
- Reconstituted solution: Once Ampitar powder has been reconstituted into a solution for injection or infusion, it must be used immediately. Reconstituted ampicillin solutions are unstable and should not be stored for later use. The solution should be visually inspected before administration—it should be clear and essentially free from visible particles.
- Keep out of reach of children: Store all medicines safely where children cannot see or reach them.
- Expiry date: Do not use Ampitar after the expiry date stated on the carton and label after “EXP.” The expiry date refers to the last day of the stated month.
- Disposal: Do not dispose of medicines via wastewater or household waste. Ask your pharmacist how to dispose of medicines that are no longer needed. These measures help protect the environment.
Ampitar appears as a white to pale yellow powder. When reconstituted, the solution has a pH of 8.0–10.0. If the powder has changed color significantly or the reconstituted solution appears cloudy or contains visible particles, do not use it and inform your pharmacist.
What Does Ampitar Contain?
Ampitar has a simple formulation consisting solely of the active pharmaceutical ingredient:
- Active substance: Ampicillin, supplied as ampicillin sodium.
- Ampitar 1 g: Each injection vial contains 1 g of ampicillin (as ampicillin sodium).
- Ampitar 2 g: Each injection vial contains 2 g of ampicillin (as ampicillin sodium).
- Other ingredients: None. Ampitar contains no additional excipients beyond the active substance.
Note on sodium content: Because the active substance is supplied as ampicillin sodium salt, each vial contains a significant quantity of sodium (70.2 mg per 1 g vial and 140.4 mg per 2 g vial). For detailed sodium content information, refer to the Sodium Content section above.
Packaging: Ampitar is available in cartons containing 1 or 10 injection vials. The vials are made of glass and sealed with a rubber stopper and aluminum cap.
Marketing authorization holder: Tarchomińskie Zakłady Farmaceutyczne “Polfa” Spółka Akcyjna, Warsaw, Poland, with local representation by EQL Pharma AB.
Ampitar is authorized and marketed across the European Economic Area under the same brand name (Ampitar) in multiple countries including Poland and the Nordic region.
Frequently Asked Questions About Ampitar
Ampitar contains ampicillin, while amoxicillin is a closely related but distinct aminopenicillin. Both are broad-spectrum penicillin antibiotics, but they differ in several important ways. Amoxicillin was developed as a modification of ampicillin to improve oral absorption (70–80% versus 40–50% for oral ampicillin), making it the preferred choice for oral therapy of mild to moderate infections. Ampitar (injectable ampicillin), on the other hand, is used for severe infections requiring parenteral administration. Ampicillin has certain advantages over amoxicillin in specific clinical situations, particularly for meningitis due to Listeria monocytogenes and for enterococcal endocarditis. The two drugs have similar but not identical antibacterial spectra.
Ampicillin can be used during pregnancy when the physician considers it medically necessary. Penicillins are generally considered among the safest antibiotics for use in pregnancy, and ampicillin has a long history of clinical use in pregnant women without evidence of teratogenic effects. It crosses the placental barrier but has not been shown to harm the developing fetus. In fact, ampicillin is specifically recommended for certain infections during pregnancy and labor, including Group B Streptococcus (GBS) prophylaxis during labor in women who are allergic to first-line penicillin but without a history of anaphylaxis. The decision should always be made by the treating physician based on a careful risk-benefit assessment.
Ampitar is formulated as an injectable product because parenteral (intravenous or intramuscular) administration achieves 100% bioavailability and much higher blood and tissue concentrations compared to oral administration. This is critical for the treatment of serious, life-threatening infections such as bacterial meningitis, septicemia, and endocarditis, where rapid achievement of bactericidal antibiotic levels is essential for patient survival. Intravenous ampicillin also achieves adequate concentrations in the cerebrospinal fluid (CSF) when the meninges are inflamed, which is necessary for treating bacterial meningitis. Once a patient’s condition has improved and they can take oral medication, doctors may switch to an oral antibiotic (step-down therapy) to complete the course.
Like all antibiotics, inappropriate or excessive use of ampicillin can contribute to the development of antibiotic resistance. Many bacterial species have already developed resistance to ampicillin through the production of beta-lactamase enzymes that break down the drug. The World Health Organization (WHO) classifies ampicillin as an “Access” antibiotic under the AWaRe system, meaning it should be widely available for appropriate indications but used responsibly. Ampitar should only be used to treat infections caused by bacteria confirmed or strongly suspected to be susceptible to ampicillin. Completing the full prescribed course is important to minimize the selection of resistant bacteria.
The duration of treatment with Ampitar varies depending on the type and severity of infection. For most serious infections, treatment typically lasts 7–14 days, but some conditions require longer courses. Bacterial meningitis is usually treated for 10–21 days depending on the causative organism. Endocarditis treatment can last 4–6 weeks. Your doctor will determine the appropriate duration based on your clinical response, laboratory results, and established treatment guidelines. It is essential not to stop treatment early, even if you feel better, as this can lead to relapse with bacteria that are harder to treat. When clinically appropriate, your doctor may switch you from intravenous ampicillin to an oral antibiotic to complete the course at home.
Yes, Ampitar is used extensively in pediatric medicine, including in newborns and premature infants. Ampicillin is one of the first-line antibiotics for neonatal sepsis and meningitis, often used in combination with gentamicin. Dosing is based on body weight and is adjusted according to the child’s age and renal maturity. Neonates and premature infants typically receive lower doses at less frequent intervals (every 12 hours instead of every 6 hours) because their kidneys are less mature and excrete the drug more slowly. For bacterial meningitis in children, the dose may be increased to up to 400 mg/kg/day. Your doctor will calculate the precise dose appropriate for your child.
References
- World Health Organization (WHO). WHO Model List of Essential Medicines – 23rd List, 2023. Geneva: World Health Organization; 2023. Available from: who.int
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- British National Formulary (BNF). Ampicillin Monograph. NICE Evidence Services; 2024. Available from: bnf.nice.org.uk
- U.S. Food and Drug Administration (FDA). Ampicillin for Injection – Prescribing Information. U.S. Department of Health and Human Services; 2023.
- Tunkel AR, Hartman BJ, Kaplan SL, et al. Practice Guidelines for the Management of Bacterial Meningitis. Clinical Infectious Diseases. 2004;39(9):1267–1284. doi:10.1086/425368
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- Infectious Diseases Society of America (IDSA). Clinical Practice Guidelines by the Infectious Diseases Society of America for the Treatment of Methicillin-Resistant Staphylococcus aureus Infections in Adults and Children. Clinical Infectious Diseases. 2011;52(3):e18–e55.
- World Health Organization (WHO). AWaRe Classification of Antibiotics for Evaluation and Monitoring of Use, 2021. Geneva: World Health Organization; 2021.
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Editorial Team
This article was written and reviewed by the iMedic Medical Editorial Team, which includes board-certified physicians specializing in clinical pharmacology, infectious disease medicine, and antimicrobial therapy. Our editorial process follows the GRADE evidence framework, and all medical claims are verified against peer-reviewed sources and international clinical guidelines.
All content is independently reviewed by our Medical Review Board, which includes specialists in infectious disease and clinical pharmacology. Our team has no conflicts of interest and receives no pharmaceutical industry funding.
This article is based on Level 1A evidence from systematic reviews, randomized controlled trials, and authoritative clinical guidelines from WHO, EMA, FDA, BNF, and IDSA. All sources are peer-reviewed and referenced below.