Rhea Amoxicillin

Amoxicillin trihydrate.

Each capsule contains 500 mg Amoxicillin.

Pharmacology: Pharmacodynamics: Amoxicillin is a semi-synthetic aminopenicillin of the beta-lactam group of antibiotics. It has a broad spectrum of antibacterial activity against many Gram-positive and Gram-negative micro-organisms, 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.
It is rapidly bactericidal and possesses the safety profile of a penicillin.
The prevalence of acquired resistance is geographically and time dependent and for select species may be very high. Local information on resistance is durable, particularly when treating severe infections. (See Table 1.)

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Pharmacokinetics: Amoxicillin is well absorbed. Oral administration, usually at convenient three times a day dosage, produces high serum levels independent of the time at which food is taken. Amoxicillin gives good penetration into bronchial secretions and high urinary concentrations of unchanged antibiotic.
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.
The major route of elimination for Amoxicillin is via the kidney. Approximately 60 to 70% of amoxicillin is excreted unchanged in urine during the first six hours after administration of a standard dose. The elimination half-life is approximately one hour. Amoxicillin is also partly excreted in the urine as the inactive penicilloic acid in quantities equivalent to 10 to 25% of the initial dose.
Concurrent administration of probenecid delays Amoxicillin excretion.
Small amounts of the drug are also excreted in faeces and bile.

Amoxicillin-clavunate should be used in accordance with local official antibiotic-prescribing guidelines and local susceptibility data.
Amoxicillin is a broad spectrum antibiotic indicated for the treatment of commonly occurring bacterial infections such as: Upper respiratory tract infections e.g. ear, nose and throat infections, otitis media; Lower respiratory tract infections e.g acute exacerbations of chronic bronchitis, lobar and bronchopneumonia; Gastrointestinal tract infections e.g. typhoid and paratyphoid fever; Genito-urinary tract infections e.g cystitis, urethritis, pyelonephritis, bacteriuria in pregnancy, septic abortion, puerperal sepsis; Other incfections including Borreliosis (Borrelia burgdorferi) (Lyme disease); Skin and soft tissue infections; Biliary tract infections; Bone infections; Pelvic infections; Gonorrhoea (non-penicillinase producing strains); Septicaemia; Endocarditis; Meningitis; Peritonitis; Dental abscess (as an adjunct to surgical management) Helicobacter pylori eradication in peptic (duodenal and gastric) ulcer disease.
Infections such as septicaemia, endocarditis and meningitis due to susceptible organisms should be treated initially with high doses of a parenteral therapy and, where appropriate, in combination with another antibiotic.
Prophylaxis of endocarditis: Amoxicillin may be used for the prevention of bacteraemia associated with procedures such as dental extraction, in patients at risk of developing endocarditis (see Dosage & Administration).
Susceptibility to Amoxicillin will vary with geography and time and local susceptibility data should be consulted where available and microbiological sampling and susceptibility testing where necessary (see Pharmacology: Pharmacodynamics under Actions).

Adults and children over 40 kg: Standard adult dosage: 250 mg 3 times daily, increasing to 500 mg 3 times daily for more severe infections.
High dosage therapy (maximum recommended oral dosage 6 g daily in divided doses): A dosage of 3g twice daily is recommended in appropriate cases for the treatment of severe or recurrent purulent infection of the respiratory tract.
Short course therapy: Simple acute urinary tract infection: two 3 g doses with 10 to 12 hours between the doses. Dental abscess: two 3 g doses with 8 hours between the doses. Gonorrhoea: single 3 g dose.
Eradication of H. Pylori: Amoxicillin 750 mg to 1 g twice daily in combination with a proton pump inhibitor (e.g. omeprazole, lansoprazole) and another antibiotic (e.g. clarithromycin, metrinodazole) for 7 days.
Children under 40 kg: Standard children's dosage: 125 mg 3 times daily, increasing to 250 mg 3 times daily for more severe infections. Amoxicillin 100mg/mL Powder for Suspension (Oral Drops) is recommended for children under 6 months of age. Acute otitis media: 750 mg twice a day for 2 days may be used as an alternative course of treatment.
Patients with renal impairment: In renal impairment the excretion of the antibiotic will be delayed and, depending on the degree of impairment, it may be necessary to reduce the total daily dosage according to the following scheme: Adults and Children over 40 kg: Mild impairment (creatinine clearance greater than 30 ml/min): No change in dosage.
Moderate impairment (creatinine clearance 10 to 30 ml/min): 500 mg twice a day maximum.
Severe impairment (creatinine clearance less than10 ml/min): 500 mg/day maximum.
Children under 40 kg: Mild impairment (creatinine clearance greater than 30 ml/min): No change in dosage.
Moderate impairment (creatinine clearance 10 to 30 ml/min): 15 mg/kg twice a day (maximum 500 mg/twice daily)
Severe impairment (creatinine clearance less than 10 ml/min): 15 mg/kg once a day (maximum 500 mg)
Patients receiving peritoneal dialysis: Amoxicillin maximum 500 mg/day. Dosing as for patients with severe renal impairment (creatinine clearance less than 10 ml/min). Amoxicillin is not removed by peritoneal dialysis.
Patients receiving haemodialysis: Dosing as for patients with severe renal impairment (creatinine clearance less than 10 ml/min).
Amoxicillin is removed from the circulation by haemodialysis. Therefore, 1 additional dose (500 mg for adults or 15 mg/kg for children under 40 kg) may be administered during dialysis and at the end of each dialysis.
PROPHYLAXIS OF ENDOCARDITIS: (see Table 2.)

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Parenteral therapy is indicated if the oral route is considered impracticable or unsuitable, and particularly for the urgent treatment of severe infection.

Gastrointestinal effects such as nausea, vomiting and diarrhea may be evident and symptoms of water/electrolyte imbalance should be treated symptomatically, Amoxicillin crystalluria, in some cases leading to renal failure, has been observed (see Precautions). Amoxicillin can be removed from the circulation by haemodialysis.

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 or cephalosporins. Serious and occasionally fatal hypersensitivity (anaphylactoid) reactions have been reported in patients on penicillin therapy. These reactions are more likely to occur in individuals with a history of hypersensitivity to beta lactam antibiotics (see Contraindications). If an allergenic 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 also occasionally result in overgrowth of non-susceptible organisms.
Pseudomembranous colitis has been reported with the use of antibiotics and may range in severity from mild to life-threatening. Therefore, it is important to consider its diagnosis in patients who develop diarrhea during or after antibiotic use. If prolonged or significant diarrhea occurs or the patient experiences abdominal cramps, treatment should be discontinued immediately and the patient investigated further.
Dosage should be adjusted in patients with renal impairment (see Dosage & Administration).
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 (see Overdosage).
Abnormal prolongation of prothrombin time (increased INR) has been reported rarely in patients receiving Amoxicillin and oral anticoagulants. Appropriate monitoring should be undertaken when anticoagulants are prescribed concurrently. Adjustments in the dose of oral anticoagulants may be necessary to maintain the desired level of anticoagulation.
Effects on Ability to Drive and Use Machines: Adverse effects on the ability to drive or operate machinery have not been observed.

The safety of this medicinal product 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 of up to 10 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 given during 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 breast-fed infant.

The following convention has been utilised for the classification of undesirable effects: Very common (≥1/10); common (≥1/100 to <1/10); uncommon (≥1/1,000 to <1/100); rare (≥1/10,000 to <1/1,000); very rare (<1/10,000). The majority of the side-effects listed below are not unique to Amoxicillin and may occur when using other penicillins. Unless otherwise stated, the frequency of adverse events (AEs) has been derived from more than 30 years of post-marketing reports. (See Table 3.)

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Probenecid decreases the renal tubular secretion of Amoxicillin. Concomitant use with Amoxicillin may result in increased and prolonged blood levels of Amoxicillin.
In common with other antibiotics, Amoxicillin may affect the gut flora, leading to lower oestrogen reabsorption and reduced efficacy of combined oral contraceptives.
Concurrent administration of allopurinol during treatment with Amoxicillin can increase the likelihood of allergic skin reactions. 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.
In the literature there are rare cases of increased international normalised ratio in patients maintained on acenocoumarol or warfarin and prescribed a course of Amoxicillin. If co-administration is necessary, the prothrombin time or international normalised ratio should be carefully monitored with the addition or withdrawal of Amoxicillin.

Store at temperatures not exceeding 25°C.

Penicillins

J01CA04 - amoxicillin ; Belongs to the class of penicillins with extended spectrum. Used in the systemic treatment of infections.

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