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Capsule, powder filled, Size 2, yellow opaque cap and body, approximately 17.5 mm length and 6.3 mm diameter. Each capsule contains Amoxicillin Trihydrate Ph Eur equivalent to amoxicillin 250 mg.
Capsule, powder filled, Size 0, yellow opaque cap and body, approximately 21.2 mm length and 7.6 mm diameter. Each capsule contains Amoxicillin Trihydrate Ph Eur equivalent to amoxicillin 500 mg.
Suspension, oral, powder for, white to yellowish colour. Reconstituted suspension contains in 5 ml, Amoxicillin Trihydrate Ph Eur equivalent to amoxicillin 125 mg.
Suspension, oral, powder for, white to yellowish colour. Reconstituted suspension contains in 5 ml, Amoxicillin Trihydrate Ph Eur equivalent to amoxicillin 250 mg.
Suspension, oral, granules for, white to yellowish colour. Reconstituted suspension contains in 1 ml, Amoxicillin Trihydrate Ph Eur equivalent to amoxicillin 100 mg.
Amoxicillin is an aminobenzyl penicillin that has a bactericidal action due to its inhibition of the synthesis of the bacterial cell wall. It exerts a bactericidal effect against many Gram-positive and Gram-negative microorganisms. Amoxicillin is not effective against beta-lactamase producing organisms.
J01CA04 - Penicillins with extended spectrum.
Amoxicillin is a semi-synthetic aminopenicillin of the beta-lactam group of antibiotics.
Amoxicillin has a broad spectrum of antibacterial activity against many Gram-positive and Gram-negative microorganisms, acting through the inhibition of biosynthesis of cell wall mucopeptide. Amoxicillin is, however, susceptible to degradation by beta-lactamases and therefore the spectrum of activity does not include organisms which produce these enzymes including resistant staphylococci, and all strains of Pseudomonas, Klebsiella and Enterobacter.
The prevalence of resistance may vary geographically and with time for selected species and local information on resistance is desirable, particularly when treating severe infections. As necessary, expert advice should be sought when the local prevalence of resistance is such that the utility of the agent in at least some types of infections is questionable.
The MIC breakpoints for susceptible organisms vary according to species. Enterobacteriaceae are considered susceptible when inhibited at NMT 8 mcg/ml amoxicillin and resistant at NLT 32 mcg/ml.
From NCCLS recommendations and using NCCLS-specified methods, M. catarrhalis (beta-lactamase negative) and H. influenzae (beta-lactamase negative) are considered susceptible at NMT 1 mcg/ml and resistant at NLT 4 mcg/ml; Str. pneumoniae are considered susceptible to amoxicillin at MIC NMT 2 mcg/ml and resistant at NLT 8 mcg/ml.
Strains of the following named organisms are generally sensitive to the bactericidal action of amoxicillin in vitro.
Susceptible Gram-positive aerobes include: Enterococcus faecalis (Note 2), Streptococcus pneumoniae (Notes 1, 3), Streptococcus pyogenes (Notes 1, 3), Streptococcus viridans (Note 2), Streptococcus agalactiae, Streptococcus bovis, Staphylococcus aureus (penicillin sensitive), Corynebacterium species (Note 2), Bacillus anthracis, Listeria monocytogenes.
Susceptible Gram-negative aerobes include: Haemophilus influenzae (Note 3), Haemophilus parainfluenzae (Note 3), Escherichia coli (Note 3), Proteus mirabilis, Salmonella species (Note 2), Shigella species (Note 2), Bordetella pertussis, Brucella species (Note 1), Neisseria gonorrhoeae (Note 2), Neisseria meningitidis (Note 1), Pasteurella septica, Helicobacter pylori, Leptospira spp, Vibrio Cholerae
Susceptible anaerobes include: Bacteroides melaninogenicus (Note 2), Clostridium species, Fusobacterium spp. (Note 2), Peptostreptococci
Other susceptible organisms include Borrelia burgdorferi.
Note 1: No beta-lactamase producers have as yet been reported for these
bacterial species.
Note 2: Inconstantly susceptible; susceptibility is therefore unpredictable in
the absence of susceptibility testing.
Note 3: Clinical efficacy has been demonstrated for susceptible isolates in
approved clinical indications.
Bacteria may be resistant to amoxicillin due to production of beta-lactamases which hydrolyse aminopenicillins, due to alteration in penicillin-binding proteins, due to impermeability to the drug, or due to drug efflux pumps. One or more of these mechanisms may co-exist in the same organism, leading to a variable and unpredictable cross-resistance to other beta-lactams and to antibacterial drugs of other classes.
Resistant Gram-positive aerobes include: Staphylococcus (beta-lactamase producing strains).
Resistant Gram-negative aerobes include: Acinetobacter spp., Citrobacter spp., Enterobacter spp., Klebsiella spp., Moraxella catarrhalis (non-susceptible isolates), Proteus spp. (indole positive), Proteus vulgaris, Providencia spp., Pseudomonas spp., Serratia spp.
Resistant anaerobes include: Bacteroides fragilis.
Other resistant organisms include: Chlamydia, Mycoplasma, Rickettsia.
Amoxicillin is rapidly absorbed from the gut to an extent of 72 to 93%. Absorption is independent of food intake. Peak blood levels are achieved 1 to 2 hours after administration. After 250 and 500 mg doses of amoxicillin, average peak serum concentrations of 5.2 mcg/ml and 8.3 mcg/ml respectively have been reported.
Amoxicillin is not highly protein bound. Approximately 18% of total plasma drug content is bound to protein. Amoxicillin diffuses readily into most body tissues and fluids, with the exception of the brain and spinal fluid. Inflammation generally increases the permeability of the meninges to penicillins and this may apply to amoxicillin. Amoxicillin crosses the placenta and a small percentage is excreted into the breast milk.
Approximately 60 to 70% of amoxicillin is excreted unchanged in urine during the first 6 hours after administration of a standard dose. Amoxicillin is also partly excreted in the urine as the inactive penicilloic acid in quantities equivalent to 10 to 25% of the initial dose.
The major route of elimination for amoxicillin is via the kidney. Small amounts of the drug are also excreted in faeces and bile. The elimination half life is approximately 1 hour. Concurrent administration of probenecid delays amoxicillin excretion. In patients with end-stage renal failure, the half-life ranges between 5 to 20 hours. The substance is haemodialysable.
Ospamox is indicated in the treatment of infections due to susceptible organisms.
Ospamox may be useful in instituting therapy prior to bacteriology; however bacteriological studies to determine the causative organisms and their sensitivity to amoxicillin should be performed.
Ospamox may be used for the prevention of bacteraemia, associated with procedures such as dental extraction, in patients at risk of developing bacterial endocarditis.
For upper respiratory tract infections due to streptococci, pneumococci, non-penicillinase-producing staphylococci and H. influenzae) or Genito-Urinary Tract Infections (due to Escherichia coli, Proteus mirabilis and Streptococcus faecalis or Skin and Soft Tissue Infections due to streptococci, sensitive staphylococci and Escherichia coli:
Adults: 250 mg every 8 hours.
Children (under 20 kg): 25 mg/kg/day in equally divided doses every 8 hours.
In severe infections or those caused by less susceptible organisms, 500 mg every 8 hours for adults and 50 mg/kg/day in equally divided doses every 8 hours for children may be needed.
For lower respiratory tract infections (due to streptococci, pneumococci, non-penicillinase producing staphylococci and H. influenzae:
Adults: 500 mg every 8 hours.
Children (under 20 kg): 50 mg/kg/day in equally divided doses every 8 hours.
The maximum recommended oral dosage 6 g daily in divided doses. An adult dosage of 3 g twice daily is recommended in appropriate cases for the treatment of severe or recurrent purulent infection of the respiratory tract.
Prophylaxis for patients undergoing extraction, scaling or surgery involving gingival tissues who have not received a penicillin in the previous month. Patients with prosthetic heart valves should be referred to hospital (see below).
Adults - 3 g orally, 1 hour before procedure. A second dose may be given 6 hours later if considered necessary. Children under 10 - half the adult dose. Children under 5 - quarter adult dose.
Adults - initially 3 g orally 4 hours prior to anaesthesia followed by 3 g
orally (or 1 g amoxicillin/ampicillin IM if the dose is not tolerated) 6 hours
after the initial dose.
Children under 10 - half adult dose.
Children under 5 - quarter adult dose.
Adults - 1 g amoxicillin IM immediately before induction with 500 mg orally 6
hours later.
Children under 10 - half adult dose.
Note: If prophylaxis with amoxicillin is given twice within one month, emergence of resistant streptococci is unlikely to be a problem. Alternatively, antibiotics are recommended if more frequent prophylaxis is required, or the patient has received a course of treatment with a penicillin during the previous month.
Adults - Initially 1 g amoxicillin/ampicillin with 120 mg gentamicin IM immediately prior to anaesthesia (if given) or 15 minutes prior to dental procedure, followed by 500 mg Ospamox orally, 6 hours later.
Children under 10 - the dose of amoxicillin should be half the adult dose. The dose of gentamicin should be 2 mg/kg.
Note: Amoxicillin and gentamicin should not be mixed in the same syringe. Please consult the appropriate Data Sheet for parenteral amoxicillin and gentamicin.
Adults: 3 g as single dose. Cases of gonorrhoea with a suspected lesion of syphilis should have dark field examinations before receiving amoxicillin and monthly serological tests for a minimum of four months.
For acute, uncomplicated lower urinary tract infections (due to Escherichia coli, Proteus mirabilis, Streptococcus faecalis, non-penicillinase producing staphylococci):
Adults: 3 g as a single dose.
NOTE: The children's dose is intended for individuals whose weight will not cause dosage to be calculated greater than that recommended for adults. Children weighing more than 20 kg should be dosed according to the adult recommendations.
It should be recognised that in the treatment of chronic urinary tract infections, frequent bacteriological and clinical appraisals are necessary. Smaller doses than those recommended above should not be used. In stubborn infections, therapy may be required for several weeks. It may be necessary to continue clinical and/or bacteriological follow-up for several months after cessation of therapy.
Treatment should be continued for a minimum of 48 to 72 hours beyond the time that the patient becomes asymptomatic or evidence of bacterial eradication has been obtained.
It is recommended that there be at least 10 days treatment for any infection caused by haemolytic streptococci to prevent the occurrence of rheumatic fever or glomerulonephritis.
In renal impairment the excretion of amoxicillin will be delayed. Depending on the degree of impairment, it may be necessary to reduce the total daily dosage. No dosage adjustment is required in patients with a creatinine clearance > 30 ml/min. The maximum recommended dose in patients with creatinine clearance between 10 and 30 ml/min is 500 mg twice daily. The maximum recommended dose in patients with a creatinine clearance < 10 ml/min is 500 mg/day.
In patients receiving peritoneal dialysis, the maximum recommended dose in 500 mg/day. Amoxicillin may be removed from the circulation by haemodialysis.
In the majority of cases, parenteral therapy will be preferred.
Amoxicillin is a penicillin and should not be given to patients with a history of hypersensitivity to beta-lactam antibiotics (eg. penicillins, cephalosporins).
Before initiating therapy with amoxicillin, careful enquiry should be made concerning previous hypersensitivity reactions to penicillins, cephalosporins. Cross-sensitivity between penicillins and cephalosporins is well documented.
Serious and occasionally fatal hypersensitivity reactions (anaphylaxis) have been reported in patients receiving beta-lactam antibiotics. If an allergic reaction occurs, amoxicillin should be discontinued and appropriate alternative therapy instituted. Serious anaphylactic reactions may require immediate emergency treatment with adrenaline. Oxygen, intravenous steroids and airway management, including intubation, may also be required.
Amoxicillin should be avoided if infectious mononucleosis is suspected since the occurrence of a morbilliform rash has been associated with this condition following the use of amoxicillin.
Prolonged use may occasionally result in overgrowth of non-susceptible organisms.
Pseudomembranous colitis should be borne in mind if severe persistent diarrhoea occurs (in most cases caused by Clostridium difficile).
Prolongation of prothrombin time has been reported rarely in patients receiving amoxicillin. Appropriate monitoring should be undertaken when anticoagulants are prescribed concurrently.
Dosage should be adjusted in patients with renal impairment (refer to Dosage and administration).
Ospamox Suspensions, which contain aspartame, should be used with caution in patients with phenylketonuria.
Ospamox Paediatric Drops contain sucrose and saccharin sodium as sweeteners.
Ospamox Powder for Oral Suspension and Ospamox Paediatric Drops contain sodium benzoate.
In patients with reduced urine output crystalluria has been observed very rarely, predominantly with parenteral therapy. During the administration of high doses of amoxicillin, it is advisable to maintain adequate fluid intake and urinary output in order to reduce the possibility of amoxicillin crystalluria (refer to Overdosage).
The presence of high urinary concentrations of amoxicillin can cause precipitation of the product in urinary catheters. Therefore, catheters should be visually inspected at intervals.
Patients suffering from severe gastrointestinal disturbances with diarrhoea and vomiting should not be treated with Ospamox, due to the risk of reduced absorption. In these cases a parenteral treatment with amoxicillin is advisable.
Ospamox should be used with caution in patients with allergic diathesis and asthma.
Precautions should be taken for children, premature infants and during the neonatal period, renal, hepatic and haematological functions should be monitored.
Assigned Category A by the Australian Drug Evaluation Committee. This category includes medicines which have been taken by a large number of pregnant women and women of childbearing age without any proven increase in the frequency of malformations or other direct or indirect harmful effects on the foetus having been observed. The safety of amoxicillin for use in human pregnancy has not been established by well controlled studies in pregnant women. Reproduction studies have been performed in mice and rats at doses up to ten times the human dose and these studies have revealed no evidence of impaired fertility or harm to the foetus due to amoxicillin. Amoxicillin may be used in pregnancy when the potential benefits outweigh the potential risks associated with treatment.
Amoxicillin may be administered during the period of lactation. With the exception of the risk of sensitisation associated with the excretion of trace quantities of amoxicillin in breast milk, there are no known detrimental effects for the infant.
This medicine is presumed to be safe or unlikely to produce an effect.
Side-effects, as with other penicillins, are uncommon and mainly of a mild and transitory nature. The majority of the side-effects listed below are not unique to amoxicillin and may occur when using other penicillins.
In this section undesirable effects are defined as follows: Common: 10%, or less, but greater than 1%; Uncommon: 1%, or less, but greater than 0.1%; Rare: 0.1% or less, but greater than 0.01%; Very rare, including isolated cases: 0.01% or less. The incidence of these adverse events was derived from clinical studies involving a total of approximately 6,000 adult and paediatric patients taking amoxicillin.
Prolonged and repeated use of the preparation can result in superinfections and colonisation with resistant organisms or yeasts such as oral and vaginal candidiasis.
Eosinophilia.
Reversible leucopenia (including severe neutropenia or agranulocytosis), reversible thrombocytopenia and haemolytic anaemia. Prolongation of bleeding time and prothrombin time (refer to Warnings and precautions).
As with other antibiotics, severe allergic reactions, including angioneurotic oedema, anaphylaxis (refer to Warnings and precautions), serum sickness and allergic vasculitis. If a hypersensitivity reaction is reported, the treatment must be discontinued. (see also Skin and subcutaneous tissue disorders).
Gastric complaints, nausea, loss of appetite, flatulence, soft stools, diarrhoea, enanthemas (particularly in the region of the mouth), dry mouth, taste disturbances. These effects on the gastrointestinal system are mostly mild and frequently disappear either during the treatment or very soon after completion of therapy. The occurrence of these side effects can generally be reduced by taking amoxicillin during meals.
Vomiting.
Mucocutaneous candidiasis and antibiotic associated colitis including pseudomembranous colitis and haemorrhagic colitis. If severe and persistent diarrhoea occurs, the very rare possibility of pseudomembranous colitis should be considered. The administration of anti-peristaltic agents is contraindicated.
Superficial tooth discolouration has been reported in children taking the oral suspensions. Good oral hygiene may help to prevent tooth discolouration as it can usually be removed by brushing.
Development of a black tongue.
Hepatitis and cholestatic jaundice. Moderate and transient increase of liver enzymes. The significance of a rise in liver enzymes is unclear
As with other antibiotics, severe allergic reactions including angioneurotic oedema, anaphylaxis (see Warnings), serum sickness and hypersensitivity vasculitis have been reported rarely. If any hypersensitivity reaction occurs, the treatment should be discontinued.
Skin rash.
Cutaneous reactions such as exanthema, pruritus, urticaria; the typical morbilliform exanthema occurs 5 to 11 days after commencement of therapy. The immediate appearance of urticaria indicates an allergic reaction to amoxicillin and therapy should therefore be discontinued.
Skin reactions such as erythema multiforme exudativum, Stevens-Johnson syndrome, toxic epidermal necrolysis, bullous and exfoliative dermatitis and acute generalised exanthematous pustulosis (see also Immune system disorders).
Interstitial nephritis, crystalluria (refer to Overdosage)
In rare cases, drug fever has been reported.
Hyperkinesia, dizziness and convulsions. Convulsions may occur in patients with impaired renal function or in those receiving high doses.
Concurrent administration of allopurinol during treatment with amoxicillin can increase the likelihood of allergic skin reactions.
Concomitant administration of amoxicillin and anticoagulants, such as coumarin, may increase the incidence of bleeding due to prolongation of prothrombin time. Appropriate monitoring should be undertaken when anticoagulants are prescribed concurrently.
There is a possibility that the bactericidal action of amoxicillin could be antagonised on co-administration with bacteriostatic agents such as macrolides, tetracyclines, sulphonamides or chloramphenicol.
An increase in the absorption of digoxin is possible on concurrent administration with amoxicillin.
Concurrent use of methotrexate with amoxicillin may result in methotrexate toxicity, possibly due to competitive inhibition of renal tubular secretion of methotrexate by amoxicillin.
Probenecid decreases the renal tubular secretion of amoxicillin. Concurrent use with amoxicillin may result in increased and prolonged levels of amoxicillin in serum and bile.
In common with other broad spectrum antibiotics, amoxicillin may reduce the efficacy of oral contraceptives and patients should be warned accordingly.
Forced diuresis leads to a reduction in blood concentrations by increased elimination of amoxicillin.
The occurrence of diarrhoea may impair the absorption of other medicines consequently limiting their efficacy.
At high risk concentrations, amoxicillin may diminish the results of serum glycaemia levels. It is recommended that when testing for the presence of glucose in urine during amoxicillin treatment, enzymatic glucose oxidase methods should be used. Due to the high urinary concentrations of amoxicillin, false positive readings are common with chemical methods.
Amoxicillin may decrease the amount of urinary estriol in pregnant women.
Amoxicillin may interfere with protein testing when colorimetric methods are used
Cases of overdosage with amoxicillin are usually asymptomatic. If encountered gastrointestinal disturbances such as nausea, vomiting and diarrhoea and symptoms of fluid-electrolyte imbalance may be evident. In patients with severely impaired renal function, large overdoses can result in signs of renal toxicity and crystalluria is possible. During the administration of high doses of amoxicillin, adequate fluid intake and urinary output must be maintained to minimise the possibility of amoxicillin crystalluria.
There is no specific antidote for an overdose of amoxicillin. Treatment consists primarily of administration of activated charcoal (a gastric lavage is usually not necessary), or symptomatic measures. Particular attention should be directed to the water and electrolyte balance of the patient. Amoxicillin can be removed from the circulation by haemodialysis.
125 mg/5 ml: Add 94 ml of water to make up 100 ml.
250 mg/5 ml: Add 92 ml of water to make up 100 ml.
Close and shake well at once. Shake well before use and use within 14 days of preparation.
100 mg/ml: Add 16 ml of water to make up 30 ml. Close and shake well at once. Shake well before use and use within 14 days of preparation.
None known.
Ospamox capsules: 48 months.
Ospamox Powder for Oral Suspension, Ospamox Paediatric Drops: 36 months.
Not applicable.
Ospamox capsules: not applicable.
Ospamox powder for oral suspension: 14 days when stored at or below 25°C.
Ospamox Paediatric Drops: 14 days when stored at or below 25°C.
Store at or below 25°C. Protect from moisture.
Store at or below 25°C. Protect from moisture.
Store at or below 25°C. Protect from light. Protect from moisture.
Prescription Medicine.
250 mg: bottles of 500 capsules.
500 mg: packs of 100 capsules in blister strips.
125 mg/5 ml: Bottle of 100 ml.
250 mg/5 ml: Bottle of 100 ml.
Bottle of 30 ml with graduated dosing syringe.
Gelatin, microcrystalline cellulose, magnesium stearate.
Guar gum, aspartame, citric acid anhydrous, sodium benzoate, talc, trisodium citrate anhydrous, colloidal anhydrous silica, lemon flavour, orange flavour, peach-apricot flavour.
Sucrose, trisodium citrate anhydrous, sodium benzoate, simethicone, guar gum, saccharin sodium, strawberry flavour, raspberry flavour, passion fruit flavour.
Novartis New Zealand Limited
Private Bag 47909 Ponsonby
AUCKLAND 1034
Telephone: (09) 361 8100
23 February 2006