Amoxil - General Information
A broad-spectrum semisynthetic antibiotic similar to ampicillin except that its resistance to gastric acid permits higher serum levels with oral administration.
Pharmacology of Amoxil
Amoxil is a moderate-spectrum antibiotic active against a wide range of Gram-positive, and a limited range of Gram-negative organisms. It is usually the drug of choice within the class because it is better absorbed, following oral administration, than other beta-lactam antibiotics. Amoxil is susceptible to degradation by β-lactamase-producing bacteria, and so may be given with clavulanic acid to increase its susceptability. The incidence of β-lactamase-producing resistant organisms, including E. coli, appears to be increasing. Amoxil is sometimes combined with clavulanic acid, a β-lactamase inhibitor, to increase the spectrum of action against Gram-negative organisms, and to overcome bacterial antibiotic resistance mediated through β-lactamase production.
Amoxil for patients
Amoxicillin is an antibiotic for treatment of infection.
Take at regular intervals, around the clock. Always finish course of therapy.
Take with or without meals.
May cause serious allergic reactions in those with penicillin allergy.
May cause nausea, vomiting and diarrhea; notify your doctor or pharmacist if these occur.
Probenecid decreases the renal tubular secretion of amoxicillin. Concurrent use of amoxicillin and probenecid may result in increased and prolonged blood levels of amoxicillin.
Chloramphenicol, macrolides, sulfonamides, and tetracy-clines may interfere with the bactericidal effects of penicillin. This has been demonstrated in vitro; however, the clinical significance of this interaction is not well documented.
Drug/Laboratory Test Interactions: High urine concentrations of ampicillin may result in false-positive reactions when testing for the presence of glucose in urine using CLINITEST, Benedictís Solution, or Fehlingís Solution. Since this effect may also occur with amoxicillin, it is recommended that glucose tests based on enzymatic glucose oxi-dase reactions (such as CLINISTIX) be used.
Following administration of ampicillin to pregnant women, a transient decrease in plasma concentration of total conjugated estriol, estriol-glucuronide, conjugated estrone, and estradiol has been noted. This effect may also occur with amoxicillin.
Carcinogenesis, Mutagenesis, Impairment of Fertility:
Long-term studies in animals have not been performed to evaluate carcinogenic potential. Studies to detect mutagenic potential of amoxicillin alone have not been conducted; however, the following information is available from tests on a 4:1 mixture of amoxicillin and potassium clavulanate (AUGMENTIN). AUGMENTIN was non-mutagenic in the Ames bacterial mutation assay, and the yeast gene conversion assay. AUGMENTIN was weakly positive in the mouse lymphoma assay, but the trend toward increased mutation frequencies in this assay occurred at doses that were also associated with decreased cell survival. AUGMENTIN was negative in the mouse micronucleus test, and in the dominant lethal assay in mice. Potassium clavulanate alone was tested in the Ames bacterial mutation assay and in the mouse micronucleus test, and was negative in each of these assays. In a multi-generation reproduction study in rats, no impairment of fertility or other adverse reproductive effects were seen at doses up to 500 mg/kg (approximately 3 times the human dose in mg/m2).
Pregnancy: Teratogenic Effects: Pregnancy Category B. Reproduction studies have been performed in mice and rats at doses up to 10 times the human dose and have revealed no evidence of impaired fertility or harm to the fetus due to amoxicillin. There are, however, no adequate and well-controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, this drug should be used during pregnancy only if clearly needed.
Labor and Delivery: Oral ampicillin-class antibiotics are poorly absorbed during labor. Studies in guinea pigs showed that intravenous administration of ampicillin slightly decreased the uterine tone and frequency of contractions but moderately increased the height and duration of contractions. However, it is not known whether use of amoxicillin in humans during labor or delivery has immediate or delayed adverse effects on the fetus, prolongs the duration of labor, or increases the likelihood that forceps delivery or other obstetrical intervention or resuscitation of the newborn will be necessary.
Nursing Mothers: 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.
Pediatric Use: Because of incompletely developed renal function in neonates and young infants, the elimination of amoxicillin may be delayed. Dosing of AMOXIL should be modified in pediatric patients 12 weeks or younger (£3 months). (See DOSAGE AND ADMINISTRATIONñNeonates and infants.)
A history of allergic reaction to any of the penicillins is a contraindication.
Additional information about Amoxil
Amoxil Indication: For the treatment of infections of the ear, nose, and throat, the genitourinary tract, the skin and skin structure, and the lower respiratory tract due to susceptible (only b-lactamase-negative) strains of Streptococcus spp. (a- and b-hemolytic strains only), S. pneumoniae, Staphylococcus spp., H. influenzae, E. coli, P. mirabilis, or E. faecalis. Also for the treatment of acute, uncomplicated gonorrhea (ano-genital and urethral infections) due to N. gonorrhoeae (males and females).
Mechanism Of Action: Amoxil binds to penicillin-binding protein 1A (PBP-1A) located inside the bacterial cell well. Penicillins acylate the penicillin-sensitive transpeptidase C-terminal domain by opening the lactam ring. This inactivation of the enzyme prevents the formation of a cross-link of two linear peptidoglycan strands, inhibiting the third and last stage of bacterial cell wall synthesis. Cell lysis is then mediated by bacterial cell wall autolytic enzymes such as autolysins; it is possible that amoxicllin interferes with an autolysin inhibitor.
Drug Interactions: Methotrexate The penicillin increases the effect and toxicity of methotrexate
Demeclocycline Possible antagonism of action
Doxycycline Possible antagonism of action
Ethinyl Estradiol This anti-infectious agent could decrease the effect of the oral contraceptive
Methacycline Possible antagonism of action
Minocycline Possible antagonism of action
Oxytetracycline Possible antagonism of action
Rolitetracycline Possible antagonism of action
Tetracycline Possible antagonism of action
Mestranol This anti-infectious agent could decrease the effect of the oral contraceptive
Food Interactions: Take without regard to meals.
Generic Name: Amoxicillin
Synonyms: Amoxicilina [INN-Spanish]; Amoxicillin anhydrous; Amoxicillin Trihydrate; Amoxicilline [INN-French]; Amoxicillinum [INN-Latin]; AMC; Amoxycillin Trihydrate; Amoxycillin; D-Amoxicillin; p-Hydroxyampicillin
Drug Category: Anti-Bacterial Agents; Penicillins
Drug Type: Small Molecule; Approved
Absorption: Rapidly absorbed after oral administration.
Toxicity (Overdose): Serious toxicity is unlikely following large doses of amoxicillin. Acute ingestion of large doses of amoxicillin may cause nausea, vomiting, diarrhea and abdominal pain. Acute oliguric renal failure and hematuria may occur following large doses.
Protein Binding: In blood serum, amoxicillin is approximately 20% protein-bound
Biotransformation: Hepatic metabolism accounts for less than 30% of the biotransformation of most penicillins
Half Life: 61.3 minutes
Dosage Forms of Amoxil: Powder, for solution Oral
Powder, for suspension Oral
Chemical IUPAC Name: (2S,5R,6R)-6-[[(2R)-2-amino-2-(4-hydroxyphenyl)acetyl]amino]-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid
Chemical Formula: C16H19N3O5S
Amoxicillin on Wikipedia: https://en.wikipedia.org/wiki/Amoxicillin
Organisms Affected: Enteric bacteria and other eubacteria