Amoxil/Amoxil Forte

Pharmacology: Amoxil is a semi-synthetic aminopenicillin of the β-lactam group of antibiotics. It has a broad spectrum of antibacterial activity against gram-positive and gram-negative microorganisms, acting through the inhibition of biosynthesis of cell wall mucopeptide. It is rapidly bactericidal and possesses the safety profile of penicillin.
Microbiology: Strains of the following organisms are generally sensitive to the bactericidal action of Amoxil in vitro: Gram-Positive: Aerobes: Streptococcus faecalis, Streptococcus pneumoniae, Streptococcus pyogenes, Streptococcus viridans, penicillin-sensitive Staphylococcus aureus, Corynebacterium spp, Bacillus anthracis, Listeria monocytogenes.
Anaerobes: Clostridium spp.
Gram-Negative: Aerobes: Haemophilus influenzae, Escherichia coli, Proteus mirabilis, Salmonella and Shigella spp, Bordetella pertussis, Brucella spp, Neisseria gonorrhoeae, Neisseria meningitidis, Pasteurella septica, Vibrio cholerae.
Amoxicillin is susceptible to degradation by β-lactamase, and therefore, the spectrum of activity of Amoxil does not include organisms which produces these enzymes, including resistant staphylococci and all strains of Pseudomonas, Klebsiella and Enterobacter.
Pharmacokinetics: Amoxil is well absorbed. Oral administration, usually at convenient 3 times daily dosage, produces high serum levels independent of the time at which food is taken. Amoxil 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 elimination half-life is approximately 1 hr. The major route of elimination for amoxicillin is via the kidney. Approximately 60-70% of Amoxil is excreted unchanged in urine during the first 6 hrs after administration of a standard dose. Amoxil is also partly excreted in the urine as the inactive penicilloic acid in quantities equivalent to 10-25% of the initial dose.
Concurrent administration of probenecid delays amoxicillin excretion.

Treatment of the following commonly occurring bacterial infections: Upper respiratory tract infections eg, tonsillitis, sinusitis, otitis media.
Lower respiratory tract infections eg, acute and chronic bronchitis, lobar and bronchopneumonia.
Genitourinary tract infections eg, cystitis, urethritis, pyelonephritis, septic abortion, puerperal sepsis.
Skin and soft tissue infections; bone infections.
Gonorrhea (non-penicillinase-producing strains); dental abscess (as an adjunct to surgical management).

Usual Dosage: Treatment of Infection: Adults and Children >40 kg: For Severe Infections: 875 mg every 12 hrs or 500 mg 3 times daily.
Gonorrhea: Single 3-g dose.
Children <40 kg: Standard Dosage: 125 mg 3 times daily, increasing to 250 mg 3 times daily for more severe infections.
Amoxil Pediatric suspension is recommended for children <6 months.
In severe or recurrent acute otitis media, especially where compliance may be a problem, 750 mg twice a day for 2 days may be used as an alternative course of treatment in children 3-10 years.
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 >40 kg: Mild Impairment (Creatinine clearance >30 mL/min): No change in dosage. Moderate Impairment (Creatinine clearance 10-30 mL/min): Maximum of 500 mg twice daily. Severe Impairment (Creatinine clearance <10 mL/min): Maximum of 500 mg/day.
Patients Receiving Hemodialysis: Dosing as for patients with severe renal impairment (Creatinine clearance <10 mL/min). They should receive an additional dose both during and at the end of dialysis.
Amoxicillin is removed from the circulation by hemodialysis. Therefore, 1 additional dose (500 mg for adults or 15 mg/kg for children <40 kg) may be administered during dialysis and at the end of each dialysis.
It should be recognized that in the treatment of chronic urinary tract infections, frequent bacteriological and clinical appraisals are necessary.
Smaller doses than those recommended previously should not be used.
Even higher doses may be needed at times. 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.
Except for gonorrhea, treatment should be continued for a minimum of 48-72 hrs beyond the time that the patient becomes symptomatic or evidence of bacterial eradication has been obtained. It is recommended that there be at least 10 days of treatment for any infection caused by Streptococcus pyogenes to prevent the occurrence of acute rheumatic fever.
Parenteral therapy is indicated if the oral route is considered impracticable or unsuitable, and particularly for the urgent treatment of severe infection.

Problems of overdosage with amoxicillin are unlikely to occur. If encountered, gastrointestinal effects eg, nausea, vomiting and diarrhea may be evident and should be treated symptomatically with attention to the water/electrolyte balance.
During the administration of high doses of amoxicillin, adequate fluid intake and urinary output must be maintained to minimize the possibility of amoxicillin crystalluria.
Amoxicillin can be removed from the circulation by hemodialysis.

Penicillin-hypersensitive patients. Attention should be paid to possible cross-sensitivity with other β-lactam antibiotics eg, cephalosporins.

Before initiating therapy with Amoxil, careful inquiry 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 β-lactam antibiotics (see Contraindications). If an allergic reaction occurs, Amoxil should be discontinued and appropriate therapy instituted. Serious anaphylactic reactions require immediate emergency treatment with epinephrine, oxygen, IV steroids, and airway management, including intubation, should also be administered as indicated.
Erythematous (morbilliform) rashes have been associated with glandular fever in patients receiving amoxicillin. Amoxil should be avoided if glandular fever is suspected.
Prolonged use may also occasionally result in overgrowth of nonsusceptible organisms.
Dosage should be adjusted in patients with renal impairment (see Dosage & Administration).
Pseudomembranous colitis has been reported with nearly all of antibacterial agents, including amoxicillin, and may range in severity from mild to life-threatening. Therefore, it is important to consider this diagnosis in patients who present with diarrhea subsequent to the administration of antibacterial agents. As with any potent drug, periodic assessment of renal, hepatic and hematopoietic function should be made during prolonged therapy.
Effects on the Ability to Drive or Operate Machinery: Adverse effects on the ability to drive or operate machinery have not been observed.
Use in pregnancy: Animal studies with Amoxil have shown no teratogenic effects. Amoxil has been in extensive clinical use since 1972 and its suitability in human pregnancy has been well documented in clinical studies. When antibiotic therapy is required during pregnancy, Amoxil may be considered appropriate when the potential benefits outweigh the potential risks associated with treatment.
Use in lactation: Penicillins have been shown to be excreted in human milk. Amoxicillin use by nursing mothers may lead to sensitization of infants. Caution should be exercised when amoxicillin is administered to a nursing woman.

Use in pregnancy: Animal studies with Amoxil have shown no teratogenic effects. Amoxil has been in extensive clinical use since 1972 and its suitability in human pregnancy has been well documented in clinical studies. When antibiotic therapy is required during pregnancy, Amoxil may be considered appropriate when the potential benefits outweigh the potential risks associated with treatment.
Use in lactation: Penicillins have been shown to be excreted in human milk. Amoxicillin use by nursing mothers may lead to sensitization of infants. Caution should be exercised when amoxicillin is administered to a nursing woman.

Side effects, as with other penicillins, are uncommon and mainly of a mild and transitory nature.
Hypersensitivity Reactions: If any hypersensitivity occurs, the treatment should be discontinued. Skin rash, pruritus and urticaria have been reported occasionally. Rarely, skin reactions eg, erythema multiforme and Stevens-Johnson syndrome, toxic epidermal necrolysis and bullous and exfoliative dermatitis have been reported.
As with other antibiotics, severe allergic reactions including angioneurotic oedema, anaphylaxis (see Precautions), serum sickness and hypersensitivity vasculitis have been reported rarely.
Interstitial nephritis can occur rarely.
Gastrointestinal Reactions: Effects include nausea, vomiting and diarrhea. Intestinal candidiasis and antibiotic-associated colitis (including pseudomembranous colitis and hemorrhagic colitis) have been reported rarely.
Hepatic Effects: A moderate rise in AST and/or ALT has been occasionally noted but the significance of this is unclear. As with other β-lactam antibiotics, hepatitis and cholestatic jaundice have been reported rarely.
Hematological Effects: As with other β-lactams, eosinophilia, reversible leucopenia (including severe neutropenia or agranulocytosis), reversible thrombocytopenia and hemolytic anemia have been reported rarely. Prolongation of bleeding time and prothrombin time has also been reported rarely (see Precautions).
Central Nervous System Effects: Central nervous system effects have been seen rarely. They include hyperkinesia, dizziness and convulsions, reversible hyperactivity, agitation, anxiety, insomnia, confusion. Convulsions may occur in patients with impaired renal function or in those receiving high doses.
Miscellaneous: Superficial tooth discoloration has been reported rarely and mostly with chewable tablets. It can usually be removed by brushing.

Probenecid decreases the renal tubular secretion of amoxicillin. Concomitant use with Amoxil may result in increased and prolonged blood levels of amoxicillin.
In common with other broad-spectrum antibiotics, Amoxil may reduce the efficacy of oral contraceptives and patients should be warned accordingly.
Concurrent administration of allopurinol during treatment with amoxicillin can increase the likelihood of allergic skin reactions.
Prolongation of prothrombin time has been reported rarely in patients receiving amoxicillin.
Appropriate monitoring should be undertaken when anticoagulants are prescribed concurrently.
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 reading are common with chemical methods.

Oral: Store in a dry place, below 25°C.
Once dispensed, Amoxil syrup SF should be stored at 25°C or below and used within 14 days. If dilution of the reconstituted SF product is required, water should be used.

Penicillins

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

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