Usage
Norfloxacin + Ornidazole is a fixed-dose combination antibiotic used to treat a variety of bacterial and protozoal infections. It is prescribed for infections of the urinary tract, gastrointestinal tract, gynecological infections (including pelvic inflammatory disease), skin and soft tissue infections, and sexually transmitted infections. It is sometimes used for surgical prophylaxis. This combination is particularly effective against mixed aerobic-anaerobic infections.
- Pharmacological Classification: Antibiotic (fluoroquinolone and nitroimidazole)
- Mechanism of Action: Norfloxacin inhibits bacterial DNA gyrase and topoisomerase IV, enzymes essential for bacterial DNA replication and repair. Ornidazole damages protozoal and anaerobic bacterial DNA, leading to microbial death. Together, they provide broad-spectrum coverage against various bacterial and parasitic pathogens.
Alternate Names
While “Norfloxacin + Ornidazole” is the standard generic name, some regional or international variations may exist. It’s marketed under several brand names such as Ornilox, KHOGYL-N, and O-CEBRAN-OZ.
How It Works
- Pharmacodynamics: Norfloxacin, a fluoroquinolone, disrupts bacterial DNA replication by inhibiting DNA gyrase and topoisomerase IV. Ornidazole, a nitroimidazole, forms reactive metabolites that damage protozoal and anaerobic bacterial DNA. The combined action results in bacterial and parasitic cell death.
- Pharmacokinetics: Both drugs are absorbed orally. Norfloxacin is partially metabolized in the liver and excreted primarily through the kidneys. Ornidazole is also metabolized in the liver and excreted in urine and feces. The pharmacokinetic parameters of both drugs may be altered in patients with hepatic or renal impairment.
- Mode of Action: Norfloxacin acts on DNA gyrase and topoisomerase IV, disrupting DNA supercoiling and replication. Ornidazole interacts with DNA, causing strand breakage and inhibiting repair. These mechanisms lead to microbial death.
- Elimination Pathways: Norfloxacin is primarily eliminated renally, with some hepatic metabolism. Ornidazole is eliminated through both renal and hepatic routes.
Dosage
Standard Dosage
Adults:
The usual dose is one tablet of Norfloxacin 200mg + Ornidazole 500mg twice daily. The dose may be increased in severe infections.
Children:
The dosage and safety of this combination in children under 8 years haven’t been established and are generally avoided. For children 8-12, a lower strength tablet (Norfloxacin 100mg + Ornidazole 250mg) is recommended, one tablet twice daily. Consult a pediatrician for appropriate dosage determination.
Special Cases:
- Elderly Patients: Dosage adjustment may be necessary based on creatinine clearance.
- Patients with Renal Impairment: Dose reduction is necessary depending on the severity of the impairment.
- Patients with Hepatic Dysfunction: Dose adjustments may be required.
- Patients with Comorbid Conditions: Conditions such as diabetes, cardiovascular diseases, or seizures might warrant special consideration and dose adjustments.
Clinical Use Cases
The dosage for specific clinical situations should be individualized based on the severity of infection, patient comorbidities, and the treating physician’s judgment. There are no specific fixed guidelines for these use cases.
- Intubation: Dose adjustments may be needed.
- Surgical Procedures: Prophylactic use may be employed, typically starting before the procedure and continuing for a short period postoperatively.
- Mechanical Ventilation: Dose adjustment may be needed.
- Intensive Care Unit (ICU) Use: Dose adjustments may be needed.
- Emergency Situations: The dosage will be at the physician’s discretion in emergencies.
Dosage Adjustments
Dose modifications are often necessary for patients with renal or hepatic dysfunction. Consult current guidelines and individual patient characteristics when making these adjustments.
Side Effects
Common Side Effects:
Nausea, vomiting, diarrhea, abdominal pain, headache, dizziness.
Rare but Serious Side Effects:
Tendinitis, tendon rupture, peripheral neuropathy, seizures, severe allergic reactions, Clostridium difficile infection, hepatic dysfunction.
Long-Term Effects:
Peripheral neuropathy, tendinopathy.
Adverse Drug Reactions (ADR):
Severe allergic reactions (anaphylaxis), Stevens-Johnson syndrome, QT prolongation, torsades de pointes.
Contraindications
Hypersensitivity to norfloxacin, ornidazole, or other fluoroquinolones or nitroimidazoles; Myasthenia gravis; Epilepsy; History of tendon disorders related to fluoroquinolone use; Pregnancy; Breastfeeding (unless benefits outweigh the risk).
Drug Interactions
Antacids, sucralfate, metal cations (reduce absorption); Warfarin (enhanced anticoagulant effect); Theophylline (increased theophylline levels); Probenecid (decreased norfloxacin clearance); Cimetidine; Corticosteroids; Nonsteroidal anti-inflammatory drugs (NSAIDs); Antidiabetic agents. Avoid milk and dairy products.
Pregnancy and Breastfeeding
Norfloxacin + Ornidazole is contraindicated in pregnancy and breastfeeding due to potential fetal risks (cartilage damage, arthropathy) and unknown effects on nursing infants. The benefit must significantly outweigh the risks before considering use in these populations.
Drug Profile Summary
- Mechanism of Action: Norfloxacin inhibits bacterial DNA gyrase and topoisomerase IV; ornidazole disrupts microbial DNA.
- Side Effects: Nausea, vomiting, diarrhea, headache, dizziness; rarely, tendinitis, tendon rupture, peripheral neuropathy.
- Contraindications: Hypersensitivity, myasthenia gravis, epilepsy, pregnancy, breastfeeding.
- Drug Interactions: Antacids, warfarin, theophylline, probenecid, cimetidine, corticosteroids, NSAIDs.
- Pregnancy & Breastfeeding: Contraindicated.
- Dosage: Adults: Norfloxacin 200 mg + Ornidazole 500 mg twice daily; children (8-12 yrs): Norfloxacin 100 mg + Ornidazole 250 mg twice daily.
- Monitoring Parameters: Renal function, liver function, signs of tendinitis, neurological status.
Popular Combinations
No specific commonly used combination exists.
Precautions
Assess renal and hepatic function; Monitor for tendinitis and peripheral neuropathy; Avoid prolonged sun exposure; Caution in patients with seizures or cardiovascular disease; Assess for drug interactions.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Norfloxacin + Ornidazole?
A: Adults: Norfloxacin 200 mg + Ornidazole 500 mg twice daily. Children (8-12 yrs): Norfloxacin 100 mg + Ornidazole 250 mg twice daily.
Q2: What are the common side effects?
A: Nausea, vomiting, diarrhea, abdominal pain, headache, dizziness.
Q3: What are the serious side effects?
A: Tendinitis, tendon rupture, peripheral neuropathy, seizures, severe allergic reactions.
Q4: Is it safe in pregnancy?
A: No, it is contraindicated in pregnancy.
Q5: Can I breastfeed while taking it?
A: No, it is contraindicated during breastfeeding.
Q6: What drugs interact with Norfloxacin + Ornidazole?
A: Antacids, warfarin, theophylline, among others. See the “Drug Interactions” section for a more comprehensive list.
Q7: How does this combination work?
A: Norfloxacin inhibits bacterial DNA replication, while Ornidazole damages microbial DNA.
Q8: What infections does it treat?
A: Urinary tract infections, gastrointestinal infections, gynecological infections, skin infections, some sexually transmitted infections.
Q9: What precautions are necessary?
A: Monitor renal and hepatic function, watch for tendinitis and neuropathy, and avoid excessive sun exposure.
Q10: What should patients do if they miss a dose?
A: Take the missed dose as soon as remembered unless it’s close to the next scheduled dose. Do not double the dose.
