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Ampilin
(Ampicillin
Capsules B.P. 250mg) and (Ampicillin Oral Suspension B.P 125mg/5ml)
(Ampicillin
Capsules B.P. 500mg)
DESCRIPTION
Capsules : Black and red Hard
Gelatin Capsules
With in print AMPILIN 250/500
Each capsule contains :
Ampicillin Trihydrate B.P
equivalent To Ampicillin B.P 250mg
Ampicillin Trihydrate B.P
equivalent To Ampicillin B.P 500mg
Suspension :
Unreconstituted : Fine, free
flowing, homogenous powder, free from lumps and substantially free from dark
specks.
Colour : white to red
Odour : Characteristic of
penicillin
Reconstituted : Free flowing
homogenous suspension, fruity odour and pink colour
Each 5ml of reconstituted
suspension contains :
Ampicillin Trihydrate B.P 143mg
Equivalent To Ampicillin B.P
125mg
ACTIONS AND MODE OF MECHANISMS
OF ACTION
Bactericidal for Gram-positive
organisms, acts by inhibiting transpeptidase, the enzyme responsible for
cross-linking of peptidoglycan during the final stage of synthesis of the
bacterial cell wall, thus exerts its effect against actively dividing
bacteria.
Bacteriostatic for Gram-negative
organisms, action resembles those of chloramphenicol and tetracycline ie by
inhibition of bacterial protein synthesis.
PHARMACOLOGY
Ampicillin is bactericidal in its
action against Gram-Positive and bacteriostatic against Gram-Negative
organisms. Those Gram positive bacteria sensitive to the therapy of
ampicillin in the concentration normally achieved in the body include
Streptococcus faecalis, Str. pneumonae and haemolytic streptococci.
Haemophilus influenzae, Salmonellae, most strains of Escherichia coli,
Neisseria gonorrhoeae, N meningitidis, Bacillus pertussis, Proteus mirabilis
and Brucella spp ( Gram-negative ). Ampicillin is also effective against
some shigella but strains can acquire resistance rapidly. Ampicillin is
inactivated by penicillinase and penicillinase-producing strains of
Staphylococcus aureus, Proteus spp., E.coli and Klebsuella spp. are
resistant. Resistance factors may occur causing resistance to ampicillin and
other antibiotics in Gram negative organisms.
Ampicillin is relatively stable
in the acid gastric secretion and is well absorbed from the G.I.T after oral
administration. Absorption is somewhat delayed in the presence of food. Peak
plasma concentrations are obtained in about 2 hours and following a dose of
500mg by mouth, are reported to range from 3 to 5 g/ml. The concentration
can be doubled by doubling the dose.
Ampicillin is widely distributed
throughout the body with therapeutic levels in joints, serosal cavities and
very high concentrations in the biliary tree ( without causing obstruction),
kidney tissues and urine. A somewhat low concentrations are found in the
cerebrospinal fluid, but therapeutic concentration is achieved when the
meninges is inflamed. It also crosses the placenta barrier and a significant
concentration persists in amniotic fluid. Ampicillin is also excrete in the
breast milk .
About 30% of an oral dose of
ampicillin is excreted in the urine in 6 hours. Renal excretion is restarted
by probenacid. Ampicillin is also excreted in the faeces, milk and tears.
INDICATIONS
Respiratory Tract Infections :
Acute and chronic bronchitis, bronchiectasis, pneumonia, tonsillitis,
pharyngitis, laryngitis, sinusitis.
Gastro-Intestinal Tract
Infections : Typhoid and paratyphoid baciliary dysentary, salmonellosis,
shigellosis, bacterial diarrhea.
Urinary Tract Infection :
Urethritis, gonorrhoeae, cystitis pyclonephritis
Soft Tissue Infections :
Ampicillin is indicated in the above infections when caused by one or more
of the following organisms, Streptococci, pneumococci, penicillin
G-sensitive staphylococci, enterococci, Haemophilus influenzae, Escherichia
coli, Proteus mirabilis, Neisseria gonorrhoeae, N. meningitidis, Shigella,
Salmonella typhosa and other Salmonella species.
CONTRA INDICATIONS
Patients known to be
hypersenstivie to ampicilin or penicillins should be given an antibiotic of
another class. Ampicillin should preferably not be given to patients with
infectious mononucleosis since they are especially susceptible to ampicillin
induced skin rashes, patients with lymphatic leukaemia and patients with
hyperuricaemia being treated with allopurinol may also be at increased risk
of developing skin rashes.
SIDE EFFECTS / ADVERSE EFFECTS
Hypersensitivity reactions are
the most common side effects and are either
a) Urticaria ( typical of
penicillin hypersensitivity )
b) Maculopapulor eruptions (
characteristic of ampicillin appears about 5 days after treatment has
finished )
Rashes are more likely to occur
in patients with history of allergy, asthma, hay fever, urticaria,
infectious mononucleosis and those who have previously demonstrated
hypersensitivity to penicillin. Rashes caused by ampicillin may be toxic
rather than allergic origin as caused by benzylpenicillina and not
necessarily a contra-indication to future treatment with ampicillin or
another penicillin.
Gastrointestinal side-effects
such as glossitis, stomatitis, black hairy tongue, nausea, vomiting,
diarrhoea and puritus can also occur with oral ampicillin therapy.
As true with all antibiotics
super-infections may occur. This incidence is more associated with oral
administration but may also occur with parenteral administration. Rarely
disorders of blood may occur and increases in serum transaminase
concentrations have occasionally been reported.
Serious and occasionally fatal
anaphylactoid reactions have been reported in patients receiving penicillin
therapy. It is more frequent following parenteral therapy but may also occur
with oral therapy.
PRECAUTIONS / WARNINGS
Precaution
1. Caution with cross-sensitivity
of ampicillin with cephalosporins, griseofluvin, penicillamine, and other
types of penicillins
2. Cautiously used when the
following medical problems exist
i) History of gastrointestinal
disease, especially ulcerative colitis, regional enteritis, or
antibiotic-associated colitis.
ii) Infectious monocucleosis /
cytomegalomonouclonais / lymphatic leukemia / lymphosarcoma.
iii) Impaired renal function
The
dosage of ampicillin will need to be reduced in patients with marked renal
impairment.
iv) Interstitial Nephritis
Ampicillin should be avoided in patients who have experienced acute
interstitial nephritis as a result of antibiotic therapy.
v) Allergic diathesis
Extreme
caution should be used in the treatment of patients with an allergic
diathesis.
vi) Pseudomembranous colitis
The use of ampicillin can lead to
the development of severe colitis as a result of colorisation with a
toxin-producing organism. The colitis an be fatal and must be treated
promptyly.
If significant diarrhoea occurs
ampicillin should be discontinued. This may be sufficient treatment in the
early stages although cholestyramine orally may help by binding the toxin to
the colonic lumen. In severe cases oral vancomycin 250mg 6 hourly for 5-10
days has proved effective. Parenteral vancomycin is not effective
3. SupraInfection :
Suprainfection with other mycotic organisms or bacteria may occur during
therapy and if it occurs, discontinued ampicillin and substitute with
appropriate treatment.
4. Prolonged Therapy : as with
any potent agent, periodic assessment of organ function should be made
during prolonged therapy.
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