Vatacil

Ampicillin sodium.

Ampicillin (Sterile Ampicillin Sodium) is a white hygroscopic powder, which is freely soluble in water. It is an aminopenicillin with a broad spectrum of activity, especially against Gram-negative bacilli and Gram-positive bacteria as well, although generally less active. The chemical name of ampicillin is 4-thia-1-azabicyclo [3.2.0] heptane-2-carboxylic acid, 6-[(aminophenyl-acetyl) amino]-3, 3-dimethyl-7-oxo, [2S-{2-5-,B(S)}].

Pharmacology: Pharmacokinetics: Absorption and Fate: Ampicillin is given by injection as the sodium salt and following the intramuscular administration of 500mg peak plasma concentrations occur within about 1 hour and are reported to range from 7-14 uq per mL. Ampicillin is widely distributed and therapeutic concentrations can be achieved in ascitic pleural and joint fluids. It crosses the placenta into the fetal circulation and small amounts are excreted in breast milk. There is little diffusion into the cerebrospinal fluid except when the meninges are inflamed. About 20% is bound to plasma proteins and the plasma half-life about 1-1.5 hours, but this may be increased in neonates and the elderly; in renal failure half-lives of 7-20 hours have been reported.
Ampicillin is metabolized to some extent to penicilloic acid, which is excreted in the urine. Renal clearance of ampicillin occurs partly by glomerular filtration and partly by tubular secretion; it is retarded by the concomitant administration of probenecid. Ampicillin is the least serum-bound of all penicillins, averaging about 20% compared to approximately 60-90% for other penicillins. Following parenteral administration about 60 to 80% is excreted in the urine within 6 hours. High concentrations are reached in bile; it undergoes enterohepatic recycling and some is excreted in the feces.
Microbiology: Ampicillin is a beta-lactam antibiotic. It is bactericidal and has a similar mode of action to that of benzylpenicillin but as an amino-penicillin with an amino group side chain attached to the basic penicillin structure, ampicillin is better able to penetrate to outer membrane of some Gram negative bacteria and has broader spectrum of activity. It resembles benzylpenicillin in the action against Gram-positive organisms including Streptococcus pneumoniae and other streptococci but, apart perhaps from Enterococcus faecalis, it is slightly less potent than benzylpenicillin. Listeria monocytogenes is highly sensitive. The Gram negative cocci Moraxella (Bramhamella) catarrhalis; Neisseria gonorrhea and N. meningitidis are sensitive. Ampicillin is more active than benzylpenicillin against some Gram negative bacilli including Haemophilus influenza and Enterobacteriacea such as Escherichia coli, Proteus mirabilis, Salmonella and Shigella spp. It is inactive against Pseudomonas aeruginosa. Ampicillin also has activity similar to benzylpenicillin against other organisms including many anaerobes and Actinomyces spp.

Ampicillin is used in the treatment of a variety of infections due to susceptible organisms. They include biliary-tract infections, bronchitis, endocarditis, epiglottis, gastroenteritis (including Escherichia coli, enteritis, salmonella enteritis and shigellosis), gonorrhea, listeriosis, bacterial meningitis, otitis media, peritonitis, pneumonia, septicemia, typhoid and paratyphoid fever and urinary tract infections.

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This product is contraindicated in those persons who have shown a hypersensitivity to the drug.

Ampicillin should be discontinued if a skin rash occurs. It should preferably not be given to patients with infectious mononucleosis since they are especially susceptible to ampicillin-induced skin rashes; patients with lymphatic leukemia or HIV infection may also be at increased risk to developing skin rashes.
Use in Pregnancy: Anaphylaxis is a fairly uncommon event in pregnancy that can have serious implications for both mother and fetus. Several central nervous system damage in the preterm fetus and death in infancy have been attributed to maternal hypotensive anaphylaxis whereas at term the fetus has been regarded as protected. Several fatal complications after intravenous application of ampicillin to a woman at term have been reported. This case demonstrates that the fetus near term may not be protected against severe damaged caused by anaphylaxis. Therefore drugs with the potential to produce anaphylactic reactions should be given with caution in pregnancies at term. Intensive fetal monitoring in anaphylactic reaction is necessary to allow rapid delivery of the infant.

Use in Pregnancy: Anaphylaxis is a fairly uncommon event in pregnancy that can have serious implications for both mother and fetus. Several central nervous system damage in the preterm fetus and death in infancy have been attributed to maternal hypotensive anaphylaxis whereas at term the fetus has been regarded as protected. Several fatal complications after intravenous application of ampicillin to a woman at term have been reported. This case demonstrates that the fetus near term may not be protected against severe damaged caused by anaphylaxis. Therefore drugs with the potential to produce anaphylactic reactions should be given with caution in pregnancies at term. Intensive fetal monitoring in anaphylactic reaction is necessary to allow rapid delivery of the infant.

Skin rashes are among the most common side effects and are generally either urticarial or maculopapular; the urticarial reactions are typical of penicillin hypersensitivity while the erythematous maculopapular eruptions are characteristics of ampicillin and often appear more than 7 days after commencing treatment. There has been controversy over whether the maculopapular rash is an allergic or toxic response, but since in practice it may be difficult to distinguish between them, skin testing for hypersensitivity may be advisable before another penicillin is used in patients who have had Ampicillin rashes. Most patients with infectious mononucleosis develop a maculopapular rash when treated with ampicillin and patients with other lymphoid disorders such as lymphatic leukemia also appear to be at higher risk.

Ampicillin may decrease the efficacy of estrogen-containing oral contraceptives. It may also affect the absorption of other drugs due to its effect on the gastrointestinal flora. The possibility of a prolonged bleeding time following oral treatment with a broad spectrum antibiotic like ampicillin should be borne in mind in patients receiving coagulants. There may be antagonism between ampicillin, a bactericidal agent and bacteriostatic agents such as Chloramphenicol, Incompatibility in vitro with other drugs may occur. An increased frequency of skin rashes has been reported in patients receiving ampicillin with allopurinol, compared with those receiving the antibiotic alone.

Intramuscular use: To prepare initial dilution for intramuscular use, add 0.9 to 1.9 mL of sterile Water for Injection or Bacteriostatic Water for Injection to each 250 mg vial and 1.2 to 1.8mL of diluent to each 500 mg vial.
Intravenous use: To prepare initial dilution for direct intermittent intravenous use, add 5 mL of Sterile Water for Injection or Bacteriostatic Water for Injection to each 250 to 500mg vial. The resulting solution should be administered slowly over a 3 to 5 min. period. More rapid administration may result in convulsive seizures.
For Administration by IV Drip: Reconstitute as directed previously (For Intravenous use) prior to diluting with IV solution. Ampicillin is stable with commonly used intravenous fluids at 23°C if infused over a period of 6 hours. Solutions should be changed after 1 hour if Ampicillin is administered in fluids containing dextrose or other carbohydrates. Ampicillin should not be mixed with blood products or proteinaceous fluids such as protein hydrolysates nor with lipid emulsions. The drug concentration and the rate and the volume of the infusions should be adjusted so that the total dose of ampicillin is administered before the drug loses its stability in use.
Directions for use: After reconstitution for intramuscular or direct intravenous use, solutions retain their potency for 4 hours. Use freshly prepared solutions only. Administer intramuscularly or intravenously within 4 hours after preparation since the potency may decrease significantly after this period.

Store at temperature not exceeding 30°C. Use immediately after preparation.

Penicillins

J01CA01 - ampicillin ; Belongs to the class of penicillins with extended spectrum. Used in the systemic treatment of infections.

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