Usage
Amoxycillin + Lactobacillus is prescribed for the treatment of bacterial infections, particularly where antibiotic-associated diarrhea is a concern. It combines the bactericidal action of amoxicillin with the gut flora-balancing effects of Lactobacillus. This combination is commonly used for respiratory tract infections (sinusitis, bronchitis, pneumonia), ear infections (otitis media), throat infections (tonsillitis, pharyngitis), skin infections, urinary tract infections (UTIs), and H. pylori infections.
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Pharmacological Classification: Antibiotic/Probiotic combination.
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Mechanism of Action: Amoxicillin inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins, ultimately leading to bacterial cell death. Lactobacillus helps restore the balance of gut microbiota, which can be disrupted by antibiotic use, thereby reducing antibiotic-associated diarrhea.
Alternate Names
There is no officially recognized alternate name for this combination. It is sometimes referred to as “Amox LB.” Brand names vary depending on the manufacturer.
How It Works
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Pharmacodynamics: Amoxicillin exerts a bactericidal effect by inhibiting bacterial cell wall synthesis, while Lactobacillus maintains the balance of intestinal flora.
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Pharmacokinetics: Amoxicillin is well-absorbed orally and distributed widely throughout the body. It is primarily excreted renally. Lactobacillus primarily exerts its effects within the gastrointestinal tract.
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Mode of Action: Amoxicillin inhibits transpeptidases and carboxypeptidases, essential enzymes for bacterial cell wall cross-linking. This results in a weakened cell wall, leading to cell lysis and bacterial death. Lactobacillus competes with pathogenic bacteria for resources and adhesion sites in the gut.
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Receptor binding, enzyme inhibition, or neurotransmitter modulation: Amoxicillin binds to penicillin-binding proteins (PBPs) in the bacterial cell wall. It does not bind to receptors in human cells or modulate neurotransmitters.
Dosage
Standard Dosage
Adults:
The typical adult dose is 250-500 mg of amoxicillin every 8 hours, or 500-875 mg every 12 hours. Lactobacillus dosages vary depending on the specific strain and formulation, typically ranging from billions to tens of billions of colony-forming units (CFUs) per day.
Children:
Pediatric dosing is weight-based: 20-40 mg/kg/day of amoxicillin, divided every 8 hours or 25-45 mg/kg/day divided every 12 hours. Lactobacillus dosing in children should be determined by a physician.
Special Cases:
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Elderly Patients: Dose adjustment may be necessary in elderly patients with impaired renal function.
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Patients with Renal Impairment: Dosage adjustment is based on creatinine clearance.
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Patients with Hepatic Dysfunction: Dose adjustment is usually not necessary.
Clinical Use Cases
Specific dosage guidelines for clinical settings such as intubation, surgical procedures, mechanical ventilation, and ICU use are not established for this combination and should be determined based on the infection being treated and the patient’s individual needs.
Dosage Adjustments
Dosage adjustments are based on renal function, hepatic function, age, and severity of infection.
Side Effects
Common Side Effects
Nausea, vomiting, diarrhea, abdominal pain or bloating, skin rash or itching are among the common side effects.
Rare but Serious Side Effects
Rare but serious side effects include Clostridium difficile infection, severe allergic reactions (anaphylaxis, serum sickness), and cholestatic jaundice.
Long-Term Effects
Long-term use of this combination may lead to antibiotic resistance and disruption of the gut microbiome.
Contraindications
Amoxicillin + Lactobacillus is contraindicated in patients with known hypersensitivity to penicillin, amoxicillin, clavulanic acid, lactobacillus, or any component of the formulation. It is also contraindicated in those with a history of cholestatic jaundice or hepatic dysfunction associated with amoxicillin or clavulanic acid use.
Drug Interactions
Amoxicillin may interact with allopurinol, probenecid, warfarin, methotrexate, and oral contraceptives. Concurrent administration of antibiotics may reduce the effectiveness of Lactobacillus. Concomitant use with alcohol should be avoided.
Pregnancy and Breastfeeding
Amoxicillin is generally considered safe during pregnancy. However, the safety of Lactobacillus during pregnancy and breastfeeding needs further research, and it is best to consult with a physician before using this combination.
Drug Profile Summary
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Mechanism of Action: Amoxicillin inhibits bacterial cell wall synthesis; Lactobacillus restores gut flora.
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Side Effects: Nausea, vomiting, diarrhea, rash, abdominal pain.
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Contraindications: Penicillin allergy, history of cholestatic jaundice/hepatic dysfunction with amoxicillin/clavulanic acid.
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Drug Interactions: Allopurinol, probenecid, warfarin, methotrexate, oral contraceptives.
Popular Combinations
Amoxycillin is sometimes combined with clavulanic acid (a beta-lactamase inhibitor) to enhance its activity against resistant bacteria.
Precautions
Assess for allergies to penicillin or other beta-lactam antibiotics. Monitor renal and hepatic function. Use cautiously in patients with a history of mononucleosis. Advise patients to maintain adequate hydration, especially if experiencing diarrhea.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Amoxycillin + Lactobacillus?
A: Adult dosage is 250-500mg amoxicillin every 8 hours, or 500-875mg every 12 hours. Pediatric dosage is weight-based (20-45mg/kg/day divided every 8-12 hours). Lactobacillus dosage is strain-dependent.
Q2: How does Lactobacillus prevent antibiotic-associated diarrhea?
A: Lactobacillus helps restore the balance of gut microbiota disrupted by antibiotics.
Q3: Can this combination be used in pregnant or breastfeeding women?
A: Amoxicillin is generally considered safe, but consult a physician before using this combination during pregnancy or while breastfeeding.
Q4: What are the common side effects?
A: Nausea, vomiting, diarrhea, rash, and abdominal pain.
Q5: What are the contraindications to using this medication?
A: Penicillin allergy and a history of cholestatic jaundice or hepatic dysfunction associated with amoxicillin/clavulanic acid.
Q6: Are there any drug interactions I should be aware of?
A: Yes, with allopurinol, probenecid, warfarin, methotrexate, and oral contraceptives.
Q7: How should I manage a patient who develops diarrhea while on this medication?
A: Advise the patient to maintain adequate hydration. Monitor for signs of Clostridium difficile infection. If diarrhea is severe or persistent, consult a physician.
Q8: Can I crush the tablets or open the capsules?
A: This depends on the specific formulation. Some formulations are designed for extended release and should not be crushed or opened. Consult the product information for details.
Q9: How should I store this medication?
A: Store at room temperature away from moisture and heat.
Q10: What should I do if a patient misses a dose?
A: Instruct the patient to take the missed dose as soon as remembered, unless it is close to the next scheduled dose. Do not double the next dose.
