Ampicillin (Principen): Description, Full List of Ingredients, Pharmacological Characteristics,  Daily Dosage and Application, Contraindications and Side Effects, Interaction with Other Drugs, Overdose Cases, Customers Testimonials

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Product name Ampicillin

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Category Antibiotics
Active ingredient Acillin
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Ampicillin (Principen): One the Best Bactericidal Agents

Ampicillin is pluripotential antibiotic falling into the group of semisynthetic penicillins. It acts in a bacillicidal way by means of inhibition of bacteria cell walls synthesis. It blocks polymerase of peptidoglycan and transpeptidase, prevents from peptide bonds and inhibits the late stages of cell walls synthesis of dividing microorganism which leads to decrease of osmotic stability of a bacterial cell and causes its lysis.

Full List of Ingredients

Full List of IngredientsActive substance: ampicillin.

Auxiliary agents: polyvinyl pyrrolidone, monosodium glutamate, disodium hydrogen phosphate or disodium phosphate, Trilon B, dextrose, vanillin, aromatic pabulary extraction (raspberry), refined sugar or refined powdered sugar.

Pharmacological Characteristics

This antibiotic has a wide spectrum of effect. It takes a germicidal action due to inhibition of bacteria cell walls synthesis. It is quite active in regards to gram-positive bacteria, such as Streptococcus spp., Listeria monocytogenes, Enterococcus spp., Staphylococcus spp., (excluding strains producing penicillinase); and aerobic gram-negative bacteria, such as Bordetella pertussis, some strains of Haemophilus influenza, Neisseria gonorrhoeae, Escherichia coli, Neisseria meningitides, Salmonella spp., Shigella spp. Ampicillin is damaged by betalactamases of bacteria. Ampicillin is moderately active against the majority of enterococci, such as Enterococcus faecalis; anaerobe bacteria including Clostridium spp.

It is inactive in regards to penicillinase-producing strains, such as Staphylococcus spp., all strains Proteus vulgaris, Pseudomonas aeruginosa; majority of strains Enterobacter spp. and Klebsiella spp., some strains Escherichia coli, mycoplasma, chlamydia, and rickettsia.

Ampicillin Pharmacokinetics


After peroral intake, Ampicillin is absorbed from gastro-intestinal tract in acid environment of the stomach. After parenteral administration (intramuscularly and intravenously), Ampicillin is found in blood plasma in high concentrations.


Ampicillin penetrates successfully into tissues and biological substances of organism, and is found in therapeutic concentrations in pleural, peritoneal and synovial liquids. It may get through placental barrier. Ampicillin can barely penetrate blood-brain barrier, but in case of inflammation of the perimyelis, the permeability coefficient of blood-brain barrier increases considerably.


30% of Ampicillin is metabolized in liver.


Elimination half-life is 1-1,5 hours. It is cleared mainly with urine. Moreover, high concentrations of unchanged medications remain in urine. Ampicillin is partly cleared with bilis. After repetitive introductions, Ampicillin doesn’t cumulate.

Daily Dosage and Application

The dosage schedule is assigned in accordance with morbidity, inflammation localization and sensitivity of causative agent. In case of oral administration, one-time dosage for adults is 250-500mg, daily dosage – 1-3g. Maximal daily dose makes 4g. Children are prescribed Ampicillin in the dose equal to 50-100mg/kg. Children weighing up to 20kg may take 12,5-25mg/kg.

The daily dose is divided into 4 intakes.

The duration of therapy depends on the severity of infection and efficiency of treatment.

  • Tablets are taken perorally regardless of food acceptance.
  • In order to prepare suspension, 62ml of distilled water is added to the bottle with powder. The ready suspension is dispensed by a special spoon which has two markings: the lower one indicates 2,5ml (125mg), the upper one – 5ml (250ml). The suspension should be drunk with water.
  • In case of parenteral administration (intramuscular/intravenously, bolus or miv), a one-time dosage is equal to 250-500mg, the daily dosage makes 1-3g; in case of severe infections, a daily dosage may be increased to 10g and more. The newly born are prescribed Ampicillin in a dose of 100mg/kg, whereas children of other age groups may take 50mg/kg. In case of severe infection process, the doses may be duplicated. A daily dose is divided into 4-6 injections with interval of 4-6 hours. The duration of intramuscular introduction is 7-14 days. Intravenous application should last 5-7 days with subsequent transition (if required) into intramuscular introduction.
  • Solution for intramuscular injection is prepared by adding 2ml of water into the contents of the bottle.
  • For bolus administration, the one-time dose of the medicine (not more than 2g) is dissolved in 5-10ml of water for injections or isotonic sodium chloride solution and is introduced slowly within 3-5 minutes (1-2g during 10-15 minutes). One-time dose surpassing 2g, the medicine is injected miv. In order to do this, one-time dose of the medication (2-4g) is dissolved in 7,5-15ml of water for injections. Then the acquired solution is added to 125-250ml of isotonic sodium chloride solution or 5-10% of glucose solution and introduced at the rate of 60-80 drops/min. For miv introduction for children, 5-10% glucose solution (30-50ml depending on age) is used in the capacity of solvent.

Solutions are used right after their preparation.

Ampicillin Indications to Use

Ampicillin Indications to UseAmpicillin is issued in the form of tablets, ampules for injections and capsules. The medication serves for destruction of a cell wall of malignant bacteria. This explains its bactericidal property. Why is this antibiotic so helpful?

  • Ampicillin in tablets is prescribed in case of inflammatory process of respiratory organs, digestive apparatus, and urinary tract caused by such microorganisms as streptococcus, staphylococcus, coliform bacterium, Proteus, salmonella, blue pus organism and Shigella.
  • The most effective form of Ampicillin is its injectable preparation – the injections are prescribed in case of sepsis, meningitis, peritonitis, disabling condition, such as pneumonitis, pyelonephritis, abdominal typhoid, whooping cough.

A patient should submit to a sensibility test before starting of therapy with Ampicillin. The instruction for the medicine reads that in the meantime, there is a variety of microorganisms resistant to antibiotics influence.

The list of possible indications to Ampicillin concerning inflammatory infections caused by sensitive to ampicillin microorganisms is the following:

  • respiratory tract infections (including bronchitis, pneumonia, pulmonary abscess);
  • ear-nose-throat infections (e.g. tonsillitis);
  • bile ducts infections (including cholecystitis, cholangitis);
  • urinary tract infections (such as pyelitis, nephropyelitis, cystitis);
  • gastrointestinal tract infections (e.g. keel disease);
  • gynecological infections;
  • skin and soft tissue infections;
  • peritonitis;
  • sepsis, bacterial endocarditis;
  • meningitis;
  • rheumatism;
  • rose;
  • scarlatina;
  • gonorrhea.


Ampicillin is not to be prescribed in case of allergic reactions caused by the intake of medications belonging to penicillin group, cephalosporins and carbapenems. Ampicillin and its analogues cannot be administered in case of severe hepatic disorder, monocytic angina, lymphatic leukemia, and severe form of dysbacteriosis. Ampicillin is counter-indicative to the patients suffering from allergic diseases, such as pollinosis, bronchial allergy, and atopic eczema.

Ampicillin Drug Interactions

Sulbactam is a mechanism-based inhibitor of betalactamase which prevents from hydrolysis and disintegration of ampicillin by betalactamases of microorganisms. In case of co-administration of ampicillin with antibacterial antibiotics (including aminoglycosides, cephalosporins, cycloserine, vancomycin, and rifampicine) synergism occurs; with bacteriostatic antibiotics (such as macrolides, chloramphenicol, lincosamides, tetracyclines, sulfanilamides) – antagonism appears.

Ampicillin enhances the effect of indirect anticoagulants inhibiting gut microflora, decreases synthesis of antihemorrhagic vitamin and prothrombin consumption index. Ampicillin reduces the effect of the medicines during the metabolism of which p-aminobenzoic acid is produced.

Probenecid, diuretics, allopurinol, phenylbutazone and non-steroidal anti-inflammatory agents reduce tubular secretion of Ampicillin which may be accompanied by increase of its concentration in blood plasma.

Antacids, glucosamine, apocathartics, aminoglycosides slow down and decrease Ampicillin absorption. Cevitamic acid increases the absorption rate of Ampicillin. Also, Ampicillin decreases the efficiency of contraceptives for peroral administration.

Possible Side-Effects

Allergic reactions: exanthematous disease, urticaria fever, Quincke’s disease, rash, exfoliative dermatitis, erythema multiforme, eosonophilia; in rare cases – anaphylactic shock.

From the part of alimentary system: nausea, vomit, diarrhea, glossitis, stomatitis, pseudomembranous colitis, intestinal dismicrobism, increment incoordination in activity of hepatic transaminases.

From the part of hematopoietic system: anemia, leukopenia, thrombocytopenia, agranulocytosis.

The effects caused by chemotherapeutic action: oral candidiasis, vaginal candidiasis, intestinal dismicrobism, colitis caused by Clostridium difficile.

Overdose Cases

In case of overdose the following effects are possible:

  • toxicity of central nervous system (vertigo, headache);
  • dyspeptic phenomena (nausea, vomit, diarrhea);
  • allergic reactions in the form of cutaneous eruption;

In case of overdose symptoms, the intake of Ampicillin should be immediately terminated. A patient is required to seek immediate medical attendance.

Administration of the Drug during Pregnancy and Breast-Feeding Period

Ampicillin may be administered during pregnancy for its main indication. The drug is emitted with maternal milk in low concentrations. If the intake of Ampicillin is required, breast feeding should be terminated.

Safety Note

Safety Note

Within the course of Ampicillin therapy, a systematic control over the function of kidneys and liver as well as peripheral blood indicators is required. Patients suffering from impairment of renal function need the correction of the dosage regime in accordance with CK indexes. The high dosage taken by patients suffering from hepatic failure may experience toxic impact on cetral nervous system. Patients suffering from bacteraemia (sepsis) may have bacteriolysis.

Analogues of Ampicillin

Ampicillin and its analogues are quite efficient and safe for patient’s health. There are a number of manufacturers issuing Ampicillin under various brand names, such as Ampicillin sodium, Ampicillin trihydrate, Standacillin, etc. Notwithstanding the fact that this medications is considered to be relatively safe for health, it should be prescribed by a doctor. A qualified specialist will make particular analyses and examination before assigning Ampicillin.

Storage Requirements

Do not store above 25 °С. Keep in dry place out of reach of sunlight. The expiration period is three years.

Customers Testimonials

Ampicillin is a quite efficient remedy for treatment of various diseases. The customer reviews demonstrate that while respecting all doctors’ recommendations, the improvement of patient’s condition occurs on the third day of therapy. Patients note that Ampicillin is well tolerated and has a few side-effects. Breast-feeding women note that Ampicillin is not recommended for usage during lactation period. This time, the impairment of baby’s intestinal normal function is adversely impacted by the drug and there is an underlying risk for disbacteriosis. – Canadian Drugs Online