Averroes Pharma
Full Prescribing Info
Ampicillin sodium.
Each vial contains Ampicillin sodium BP equivalent to Ampicillin 500 mg.
Pharmacology: Pharmacodynamics: Ampicillin exerts its action on growing and dividing bacteria by inhibiting bacterial cell wall synthesis. Benzylpenicillin inhibits the final cross-linking stage of peptidoglycan production by binding to and inactivating transpeptidases (penicillin-binding protein on the surface of the bacterial cell membrane) causing the cell wall to rupture by osmotic pressure. It is now realised that other earlier stages in cell-wall synthesis can also be inhibited by Ampicillin.
Pharmacological action: Ampicillin is bactericidal for both Gram-positive and Gram-negative organisms.
Gram-Positive Organisms: Ampicillin is active against Strep. Pyogenes, Strep. Pneumoniae and Strep. Viridans. Pneumococcal strains which are relatively resistant to penicillin G are more sensitive to Ampicillin. Group B Streptococci are always Ampicillin sensitivite, in addition Ampicillin combines with aminoglycosides such as Kanamycin, gentamicin, tobramycin or amikacin acts synergistically against these organisms resulting in accelerated streptococcal killing.
Strep. faecalis is usually sensitive to Ampicillin and often more so than penicillin G. The combination of ampicillin with streptomycin or kanamycin is synergistic against 50-75% of Strep. faecalis, whereas Ampicillin plus gentamicin or tobramycin is synergistic against nearly all such strains. Anaerobic Gram-positive cocci such as peptococcus and peptostreptococcus spp. and anaerobic streptococci are nearly always Ampicillin sensitive.
Ampicillin is destroyed by staphylococcal beta lactamase, so that most Staph. aureus and hospital acquired Staph. epidermidis are Ampicillin resistant. Staph. saprophyticus and other coagulase negative staphylococci such as Staph. hominis and haemolyticus which may be urethral isolates of young females are Ampicillin sensitive. C. diptheriae and B. anthracis are sensitive to Ampicillin. L. monocytogens is also usually sensitive to Ampicillin. Most Nocardia spp. strains are Ampicillin resistant. Anaerobic Gram-positive sporing bacillin such as Cl. Tetani, CI. Perfringens (welchii), Cl. Botulinum and other Clostridium spp. are usually Ampicillin sensitive.
Ampicillin is nearly always active against anaerobic Gram-positive asporogenous bacilli such as Actinomyces, Eubacterium, Arachnia, Propionibacterium, Bifidobacterium and Lactobacillus.
Gram-negative Organism: Ampicillin is active against many enterobacteriaceae. E. coli may be sensitive but many strains are resistant. Ampicillin resistance of E. coli is nearly always due to beta lactamase production. Proteus mirabilis is usually sensitive unless it is a beta lactamase producing strain.
Salmonella spp. is usually susceptible to Ampicillin. The Brucella spp. and B. pertussis are consistently sensitive to Ampicillin. The same is true of N. meningitidis. Branhamella catarrhalis is Ampicillin sensitive expect strains producing beta lactamase. V. cholerae and Campylobacter jejuni are usually sensitive. Gardnerella vaginalis is Ampicillin sensitive.
Some Gram-negative anaerobic bacteria such as B. melaninogenicus and Fusobacterium spp. are usually Ampicillin sensitive. Other bacteroides spp. vary in sensitivity but about 50% of isolates are inhibited by low concentrations.
Pharmacokinetics: Absorption and Serum level: Ampicillin is given by injection as the sodium salt. After intramuscular administration of 500 mg, a serum peak of 7-14 mg/lit can be expected after 1 hour.
The half life of Ampicillin is 1-2 hours and the plasma protein binding is around 20%.
Distribution: Ampicillin is distributed throughout the body and is to be found at lower concentration than in serum at most sites with the exception of the liver and kidneys. Penetration of the blood-barrier is poor except during active inflammation when a daily dose of 150 mg Ampicilin per kg may result in CSF level around 3 mg/lit.
Adequate therapeutic levels are reached in pleural, synovial and ocular fluids. Ampicillin crosses amniotic fluids during the first trimester do not reach therapeutic concentration. Some Ampicillin is secreted in the milk of a nursing mother.
Metabolism: Hepatic metabolism is a relatively unimportant route of Ampicillin elimination. About 10% of the dose in metabolised in the liver to the inactive penicilloic acid. Ampicillin esters are metabolised in the gut to the active from of the drug.
Excretion: Renal clearance of Ampicillin is slower than that of benzylpenicillin, accounting for the longer half life. Renal excretion is both by glomerular filtration & by tubular secretion. At normal oral doses 30% Ampicillin is excreted in the urine resulting in levels between 250 mg/lit & 75% of the dose may be recovered unchanged from the urine in the same period. This can be reduced by simultaneous dosage with probenecid. The half life of Ampicillin may be prolonged in patients with renal failure through no adjustment of dose is likely to be necessary, other than in very severe cases. Ampicillin is also excreted in the bile, but levels are variable & have a particular tendency to be low in the presence of a non-functional gallbladder. There is a small enterohepatic circulation of the drug & the unexcreated agent is inactivated in the liver at a slower rate than Benzylpenicillin. The kinetic of Ampicillin are unlikely to be altered in patients with hepatic dysfunction. (See table.)

Click on icon to see table/diagram/image

Acute Toxicity: Long term studies have not revealed any serious toxicity associated with Ampicillin.
Toxicology and carcinogenesis studies of Ampicillin was performed in F344/N rats and B6C3FI mice. In these studies Ampicillin was administered for 2 years to rats at doses of 0, 750 or 1500 mg and to mice at doses 0, 1500 or 3000 mg/kg. The drug was administered by oral gavage in corn oil. No toxic manifestations other than toxic lesions of the stomach were seen in rats and mice after Ampicillin administration.
Ampicillin is a broad spectrum penicillin, indicated for the treatment of a wide range of bacterial infections caused by ampicillin sensitive organisms. Typical indications include: ear, nose and throat infections, bronchitis, pneumonia, urinary tract infections, gonorrhoea, gynaecological infections, septicaemia, peritonitis, endocarditis, meningitis, enteric fever, gastro-intestinal infections.
Extraperitoneal application of Ampicillin to wounds can be used to prevent infection following abdominal surgery.
Parenteral usage is indicated where oral dosage is inappropriate.
Dosage/Direction for Use
Usual adult dosage (including elderly patients): Septicaemia, endocarditis, osteomyelitis: 500 mg four to six times a day IM or IV for one to six weeks.
Peritonitis, intra-abdominal sepsis: 500 mg four times a day IM or IV.
Meningitis: Adult dosage: 2 g six-hourly IV.
Children's dosage: 150 mg/kg daily IV in divided doses. Ampicillin may also be administered by other routes of conjunction with systemic therapy.
Intraperitoneal: 500 mg daily in up to 10 ml Water for Injections BP.
Intrapleural: 500 mg daily in 5-10 ml water for Injections BP.
Intra-articular: 500 mg daily, in up to 5 ml Water for Injections BP or sterile 0.5% procaine hydrochloride solution.
Local use in abdominal surgery: 1 g sterile powder sprinkled into the wound extraperitoneally or into muscle layers to prevent wound infection post-operatively.
Usual children's dosage (under 10 years): Half adult routine dosage.
All recommended dosages are a guide only. In severe infections, previously mentioned dosages may be increased.
Renal Impairment: In the presence of severe renal impairment (creatinine clearance <10 ml/min) a reduction in dose or extension of dose interval should be considered. In cases of dialysis, an additional dose should be administered after the procedure.
Administration: Intramuscular: Add 1.5 ml Water for Injections BP to 500 mg vial contents.
Intravenous: Dissolve 500 mg in 10 ml Water for Injections BP. Administer by slow injection (three to four minutes). Ampicillin may also be added to infusion fluids or injected, suitably diluted, into the drip tube over a period of three to four minutes.
Symptoms and Treatment of Overdose: Gastrointestinal effects such as nausea, vomiting and diarrhoea may be evident and should be treated symptomatically.
Ampicillin may be removed from the circulation by haemodialysis.
Serious and occasionally fatal hypersensitivity (anaphylactic) reactions have been reported in patients on penicillin therapy. Anaphylaxis is more frequent following parenteral therapy than oral penicillins. These reactions are more apt to occur in individuals with a history of sensitivity to multiple allergens.
Penicillin Hypersensitivity: These are cross-allerginicity between ampicillin and other penicillins, so that patients with a history of penicillin allergy may respond similarly to Ampicillin. Cross-allergenicity also occurs between penicillins and cephalosporins in a proportion of patients.
Special Precautions
Before initiating therapy with ampicillin, careful enquiry should be made concerning previous hypersensitivity reactions to beta-lactam antibiotics.
Serious and occasionally fatal hypersensitivity reactions (anaphylaxis) have been reported in patients receiving beta-lactam antibiotics. Although anaphylaxis is more frequent following parenteral therapy, it has occurred in patients on oral penicillins.
These reactions are more likely to occur in individuals with a history of beta-lactam hypersensitivity.
Ampicillin should be avoided if infectious mononucleosis and/or acute or chronic leukaemia of lymphoid origin are suspected. The occurrence of a skin rash has been associated with these conditions following the administration of ampicillin.
Prolonged use may occasionally result in overgrowth of non-susceptible organisms. Dosage should be adjusted in patients with renal impairment.
Use In Pregnancy & Lactation
Pregnancy: Animal studies with Ampicillin have shown no teratogenic effects. When antibiotic therapy is required during pregnancy, Ampicillin may be considered appropriate.
Lactation: During lactation, trace quantities of penicillins can be detected in breast milk. Adequate human and animal data on use of Ampicillin during lactation are not available.
Side Effects
Hypersensitivity reactions: If any hypersensitivity reaction occurs, the treatment should be discontinued. Skin rash, pruritus and urticaria have been reported occasionally. The incidence is higher in patients suffering from infectious mononucleosis and acute or chronic leukaemia of lymphoid origin. Purpura has also been reported. Rarely, skin reactions such as erythema multiforme and Stevens-Johnson syndrome, and toxic epidermal necrolysis have been reported.
As with other antibiotics, anaphylaxis has been reported rarely.
Renal effects: Interstitial nephritis can occur rarely.
Gastrointestinal reactions: Effects include nausea, vomiting and diarrhoea. Pseudomembranous colitis and haemorrhagic colitis has been reported rarely.
Hepatic effects: As with other beta-lactam antibiotics, hepatitis and cholelastic jaundice have been reported rarely. As with most other antibiotics, a moderate and transient increase in transaminases has been reported.
Haematological effects: As with other beta-lactams, haematological effects including transient leucopenia, transient thrombocytopenia and haemolytic anaemia have been reported rarely. Prolongation of bleeding time and prothrombin have also been reported rarely.
Drug Interactions
If Ampicillin is prescribed concurrently with an aminoglycoside, the antibiotics should not be mixed in the syringe, intravenous fluid container or giving set because loss of activity of the aminoglycoside can occur under these conditions.
Bacteriostatic drugs may interfere with the bactericidal action of ampicillin. In common with other oral broad-spectrum antibiotics, ampicillin may reduce the efficacy of oral contraceptives and patients should be warned accordingly.
Probenecid decreases the renal tubular secretion of ampicillin. Concurrent use with ampicillin may result in increased and prolonged blood levels of ampicillin. Concurrent administration of allopurinol during treatment with ampicillin can increase the likelihood of allergic skin reactions.
It is recommended that when testing for the presence of glucose in urine during ampicillin treatment, enzymatic glucose oxidase methods should be used. Due to the high urinary concentrations of ampicillin, false positive readings are common with chemical methods.
Caution For Usage
Incompatibility: Extemporaneous admixtures of beta-lactam antibacterials (penicillins and cephalosporins) and aminoglycosides may result in substantial mutual inactivation. If these groups of antibacterials are administered concurrently, they should be administered in separate sites at least 1 hour apart. Do not mix them in the same intravenous bag, bottle or tubing.
When aminoglycosides and penicillins are administered separately by different routes, a reduction of aminoglycoside serum concentration may impaired renal function when excretion of both medications is delayed.
Store below 30°C. Protect from light.
Shelf Life: 36 months from the date of manufacture if kept as recommended.
MIMS Class
ATC Classification
J01CA01 - ampicillin ; Belongs to the class of penicillins with extended spectrum. Used in the systemic treatment of infections.
Powd for inj 500 mg (white powder in glass vial) x 10's, 50's.
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