A combination of two beta-lactam antibiotics,amoxicillin and dicloxacillin, and lactobacillus. They exert their bactericidal action by inhibition of cell wall synthesis. Amoxicillin is active against a wide range of Grampositive and Gram-negative pathogens, and dicloxacillin acts against penicillinase,producing Gram-positive pathogens. Lactobacillus is an aerobic, Gram-positive,ubiquitous inhabitant of the human oral cavity, the vagina and the gastrointestinal tract. It inhibits the colonization of pathogenic bacteria on the intestinal epithelium.
This inhibitory process, known as “competitive exclusion”, can be expanded by the competition between the pathogens and the lactobacilli for the adherence sites of the intestinal mucosa, and by the inhibitory substance.
Amoxicillin is similar to ampicillin in its bactericidal action against susceptible organisms during the stage of active multiplication. It acts through the inhibition of the biosynthesis of cell wall mucopeptide. Amoxycillin has been shown to be active against most strains of the following microorganisms, both in vitro and in clinical infections:
Aerobic Gram-positive microorganisms
Staphylococcus spp.* (beta-lactamase-negative strains only)
Streptococcus spp. (alpha- and beta-hemolytic strains only)
* Staphylococci that are susceptible to amoxicillin, but resistant to methicillin/oxacillin
should be considered as resistant to amoxicillin.
Aerobic Gram-negative microorganisms
Escherichia coli (beta-lactamase-negative strains only)
Haemophilus influenzae (beta-lactamase-negative strains only)
Neisseria gonorrhoeae (beta-lactamase-negative strains only)
Proteus mirabilis (beta-lactamase-negative strains only)
Lactobacillus acidophilus therapy in the prevention and adjuvant therapy of certain infectious diseases, especially gastrointestinal disorders in children and adults, is advocated in many parts of the world. The recent emphasis on supplementation with lactobacilli is largely attributed to information obtained regarding their beneficial effects in preventing or minimizing the severity of antibiotic-associated diarrheal
episodes. Most probiotics have been designated as generally recognized as safe
Amoxicillin is stable in the presence of gastric acid and is rapidly absorbed after oral administration. The effect of food on the absorption of amoxicillin has been partially investigated. Amoxicillin diffuses readily into most body tissues and fluids, with the exception of brain and spinal fluid (except when the meninges are inflamed). The half-life of amoxicillin is 61.3 minutes. Most of the amoxicillin is excreted unchanged
in the urine; its excretion can be delayed by concurrent administration of probenecid.
In blood serum, amoxicillin is approximately 20% protein-bound. Orally administered doses of 250 mg and 500 mg amoxicillin capsules result in average peak blood levels, 1 to 2 hours after administration, in the range of 3.5 mcg/mL to 5.0 mcg/mL and 5.5 mcg/mL to 7.5 mcg/mL, respectively.
Detectable serum levels are observed up to 8 hours after an orally administered dose of amoxicillin. Following a 1 gram dose and utilizing a special skin window technique to determine levels of the antibiotic, it was noted that therapeutic levels were found in the interstitial fluid. Approximately 60% of an orally administered dose of amoxicillin is excreted in the urine within 6–8 hours.
The isoxazolyl penicillins (dicloxacillin, oxacillin, and cloxacillin) are more acidresistant and may be administered orally. Absorption after oral administration is rapid but incomplete: peak blood levels are achieved in 1–1.5 hours. In one study, after ingestion of a single 500 mg oral dose, peak serum concentrations range from 10–17 mg/mL for dicloxacillin. Oral absorption of dicloxacillin is delayed when the drug is administered after meals. It is distributed throughout the body, with the highest concentrations present in the kidneys and the liver. CSF penetration is low. It also crosses the placenta and enters into breast milk. Protein binding is 97.9 ± 0.6.
The elimination half-life is 0.7 hours, which is slightly prolonged in case of renal impairment. Non-renal elimination includes hepatic inactivation and excretion in the bile. Time to peak serum is 0.5-–2 hours. It is excreted in the feces and the urine (56–70%) as unchanged drug.
Indicated for the treatment of the following:
• Respiratory Tract Infections
Tonsillar abscess, otitis media, suppurative sinus infection, acute chronic bronchitis, bronchiectasis, bronchopneumonia, pleurisy, empyema, lung abscess, emphysema, bronchiolitis.
• Urinary Tract Infections
Acute and chronic pyelonephritis, cystitis, urethritis.
• Skin and Soft Tissue Infections
Recurrent boils, carbuncles, impetigo, cellulitis and other infected dermatoses.
• Bone Infections
Osteomyelitis and septic arthritis.
• Serious Infections
Septicemia, bacterial endocarditis, brain abscess and bacterial meningitis.
DOSAGE AND ADMINISTRATION
The dosage differs, depending on the type, site and severity of infections. The usual dosage is one capsule, three to four times daily.
In patients with severe renal impairment, the dosage should be modified by increasing the intervals between doses. With a creatinine clearance between 10 and 50 mL/min, the dosing interval can be up to 12 hours. If the clearance is less than 10 mL/min, the interval can be 16 hours.
History of allergic reaction to any of the penicillins
WARNINGS AND PRECAUTIONS
Serious and, occasionally, fatal hypersensitivity (anaphylactic) reactions have been reported in patients on penicillin therapy. Although anaphylaxis is more frequent following parenteral therapy, it has occurred in patients on oral penicillins. These reactions are more likely to occur in individuals with a history of penicillin
hypersensitivity and/or a history of sensitivity to multiple allergens. There have been reports of individuals with a history of penicillin hypersensitivity who have experienced severe reactions when treated with cephalosporins. Before initiating therapy, a detailed inquiry should be made concerning previous hypersensitivity reactions to penicillins, cephalosporins or other allergens. If an allergic reaction occurs,
It should be discontinued and appropriate therapy instituted.
Serious anaphylactic reactions require immediate emergency treatment with epinephrine. Oxygen, intravenous steroids and airway management, including intubation, should also be initiated as indicated.
Probenecid: Probenecid decreases the renal tubular secretion of amoxicillin. Concurrent use of amoxicillin and probenecid may result in increased and prolonged blood levels of amoxicillin
Oral contraceptives: In common with other antibiotics, amoxicillin may affect the gut flora, leading to lower estrogen re-absorption and reduced efficacy of combined oral estrogen/progesterone contraceptives.
Bacteriostatic drugs: Drugs such as chloramphenicol, erythromycin and tetracycline may reduce the bactericidal action of amoxicillin and cloxacillin.
Please see DOSAGE AND ADMINISTRATION.
Can be given during pregnancy. However, the drug should be used with caution.
The drug can be safely given to nursing mothers; to the baby, there is some risk of sensitization, skin rash and diarrhea.
Because of an incompletely developed renal function in neonates and young infants, the elimination of the drug may be delayed.
As with all penicillins, the side effects are generally those related to allergic response.
Symptoms of penicillin overdose include neuromuscular hypersensitivity (eg. agitation, hallucinations, asterixis, encephalopathy, confusion, and seizures).
Electrolyte imbalance may occur if the preparation contains potassium or sodium salts, especially in renal failure. Hemodialysis may aid in the removal of the drug from blood; otherwise, treatment is supportive or symptom-directed.