Usage
Lactobacillus + Norfloxacin is a combination of a probiotic and an antibiotic primarily used for the treatment of bacterial diarrhea and dysentery, especially infectious diarrhea. Norfloxacin targets gram-negative bacteria, while Lactobacillus helps to maintain the gut’s healthy bacterial balance, potentially mitigating some of the adverse gastrointestinal effects caused by the antibiotic.
- Pharmacological Classification: Antibiotic (Norfloxacin) and Probiotic (Lactobacillus)
- Mechanism of Action: Norfloxacin inhibits bacterial DNA gyrase and topoisomerase IV, enzymes essential for bacterial DNA replication and repair. Lactobacillus produces lactic acid and other substances that create an unfavorable environment for the growth of many pathogenic bacteria. It also competes with harmful bacteria for nutrients and adhesion sites.
Alternate Names
This combination medication does not have an international nonproprietary name (INN). It may be referred to by its components: norfloxacin and Lactobacillus species (e.g., Lactobacillus acidophilus). Several brand names exist, depending on the specific Lactobacillus species and the manufacturer. Examples of brand names include Norflox 400, Norflox LB, and others, often combined with “LB” or “TZ” suffixes.
How It Works
- Pharmacodynamics (Norfloxacin): Norfloxacin inhibits bacterial DNA gyrase and topoisomerase IV, essential for bacterial DNA replication, transcription, repair, and recombination. This leads to bacterial cell death.
- Pharmacokinetics (Norfloxacin): Administered orally, absorbed in the gastrointestinal tract. Metabolized in the liver, eliminated primarily via renal excretion, with a small fraction excreted in bile.
- Pharmacodynamics (Lactobacillus): Produces lactic acid, hydrogen peroxide, and bacteriocins, which inhibit the growth of pathogenic bacteria. Competes with harmful bacteria for nutrients and binding sites in the gut, helping restore gut flora balance. Improves gut barrier function.
- Pharmacokinetics (Lactobacillus): Not absorbed systematically. It acts locally in the gastrointestinal tract. Eliminated in feces.
- Elimination pathways (Norfloxacin): Primarily renal excretion and partially hepatic.
Dosage
Standard Dosage
Adults:
Norfloxacin is typically administered as 400mg twice daily. The duration of therapy can vary based on the specific infection and clinical response, generally between 3 to 7 days.
Children:
Norfloxacin is generally not recommended for children under 18 years of age due to concerns regarding cartilage development.
Special Cases:
- Elderly Patients: Careful monitoring, with possible dose adjustments for renal impairment.
- Patients with Renal Impairment: Dose adjustment based on creatinine clearance.
- Patients with Hepatic Dysfunction: Use with caution, dose adjustments may be required.
- Patients with Comorbid Conditions: Requires individualized dosing based on the condition, age and kidney functions.
Clinical Use Cases
The primary use case for this combination is infectious bacterial diarrhea. Dosage adjustments are needed based on the severity and type of infection.
Dosage Adjustments
Dosage adjustments are crucial in:
- Renal/hepatic dysfunction: Adjustments based on creatinine clearance or liver function tests.
- Metabolic disorders: Consideration for potential drug interactions.
- Genetic polymorphisms: Monitor for altered drug responses.
Side Effects
Common Side Effects:
Nausea, abdominal cramps, headache, dizziness, diarrhea.
Rare but Serious Side Effects:
Tendonitis, tendon rupture, peripheral neuropathy, QT interval prolongation, Clostridium difficile - associated diarrhea, photosensitivity, allergic reactions.
Long-Term Effects:
Long-term use not recommended.
Adverse Drug Reactions (ADR):
Anaphylaxis, Stevens-Johnson syndrome, toxic epidermal necrolysis, hepatic dysfunction, renal failure.
Contraindications
- Hypersensitivity to Norfloxacin or other fluoroquinolones.
- History of tendon disorders related to quinolone use.
- Epilepsy or other seizure disorders.
- Myasthenia gravis.
- Pregnancy and breastfeeding.
Drug Interactions
- Antacids, iron supplements, multivitamins, sucralfate, didanosine, zinc: Reduced absorption of norfloxacin. Administer at least 2 hours apart.
- Warfarin and other anticoagulants: Enhanced anticoagulant effect. Monitor INR.
- Theophylline, caffeine: Increased theophylline/caffeine levels. Monitor for toxicity.
- Nonsteroidal anti-inflammatory drugs (NSAIDs): Increased risk of seizures.
- Antidiabetic drugs: May alter blood glucose levels.
Pregnancy and Breastfeeding
Norfloxacin is contraindicated in pregnancy and breastfeeding due to potential risks to the fetus or infant.
Drug Profile Summary
- Mechanism of Action: Norfloxacin: Inhibits bacterial DNA gyrase and topoisomerase IV. Lactobacillus: Promotes a healthy gut microbiota, inhibits pathogens.
- Side Effects: Nausea, abdominal cramps, headache, dizziness, diarrhea; rarely, tendonitis, tendon rupture, peripheral neuropathy.
- Contraindications: Hypersensitivity to fluoroquinolones, tendon disorders related to quinolone use, epilepsy, myasthenia gravis, pregnancy, breastfeeding.
- Drug Interactions: Antacids, iron, multivitamins, warfarin, theophylline, NSAIDs.
- Pregnancy & Breastfeeding: Contraindicated.
- Dosage: Adults: Norfloxacin 400 mg twice daily, 3-7 days. Dose adjustments needed in renal/hepatic impairment.
- Monitoring Parameters: Renal function, liver function, signs of tendonitis, QT interval.
Popular Combinations
Lactobacillus is frequently combined with Norfloxacin and Tinidazole for treating diarrhoea and dysentery.
Precautions
- General Precautions: Assess renal and hepatic function, history of seizures, allergies.
- Specific Populations: Avoid in pregnancy, breastfeeding, and children. Use cautiously in the elderly.
- Lifestyle Considerations: Avoid alcohol, excessive caffeine, and driving until effects are known.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Lactobacillus + Norfloxacin?
A: Adults: Norfloxacin 400mg twice daily for 3-7 days, concomitant with Lactobacillus as per the specific product formulation. Dose adjustments are necessary for renal/hepatic impairment.
Q2: What are the common side effects of this combination?
A: Nausea, abdominal cramps, headache, dizziness, and diarrhea are common.
Q3: Can this medication be used during pregnancy or breastfeeding?
A: No, it is contraindicated during pregnancy and breastfeeding.
Q4: What are the serious side effects to watch out for?
A: Tendonitis, tendon rupture, peripheral neuropathy, and C. difficile infection are serious side effects that require immediate medical attention.
Q5: Are there any drug interactions I should be aware of?
A: Yes, Norfloxacin can interact with antacids, iron supplements, warfarin, theophylline, and NSAIDs. Administer medications at appropriate intervals.
Q6: How does Lactobacillus complement Norfloxacin in this combination?
A: Lactobacillus helps restore the balance of gut flora, potentially mitigating antibiotic-associated diarrhea.
Q7: Can this combination be used in children?
A: Norfloxacin is generally avoided in children under 18 due to concerns about cartilage development.
Q8: What should I do if I miss a dose?
A: Take the missed dose as soon as you remember. If it’s close to the next dose, skip the missed dose and continue with your regular schedule. Don’t double the dose.
Q9: What precautions should patients with renal impairment take?
A: Patients with renal impairment require dose adjustments of Norfloxacin based on creatinine clearance. Consult a nephrologist for precise dosage guidance.
