Can you take Flagyl (metronidazole) and Cipro (ciprofloxacin) antibiotics at the same time?

Taking Flagyl (Metronidazole) and Cipro (Ciprofloxacin) Together

Yes, Flagyl (metronidazole) and Cipro (ciprofloxacin) can be safely taken together and are actually recommended in combination for certain infections. 1, 2

Evidence Supporting Combined Use

The combination of ciprofloxacin and metronidazole is specifically recommended in several clinical scenarios:

• Intra-abdominal infections: The Infectious Diseases Society of America recommends ciprofloxacin with metronidazole as a second-choice treatment option for mild to moderate intra-abdominal infections 1

• Necrotizing fasciitis: Guidelines recommend the combination of ceftriaxone and metronidazole (with or without vancomycin) for treating necrotizing fasciitis 1

• Surgical site infections: For incisional surgical site infections after surgery of the axilla or perineum, guidelines recommend ciprofloxacin in combination with metronidazole 1

• Pelvic inflammatory disease: Research shows that ciprofloxacin with metronidazole has a 94% success rate in treating acute pelvic inflammatory disease 3

How They Work Together

The combination is effective because:

• Ciprofloxacin: Works against aerobic bacteria (bacteria that require oxygen)
• Metronidazole: Works against anaerobic bacteria (bacteria that don't require oxygen)

This provides broad-spectrum coverage for mixed infections where both types of bacteria are present.

Dosing Considerations

When taking these medications together:

• Ciprofloxacin: Typically 500-750 mg orally twice daily 4
• Metronidazole: Usually 500 mg orally twice daily or 2 g as a single dose (depending on the infection) 1

Clinical Evidence of Effectiveness

Several studies support the combined use:

• A meta-analysis found that ciprofloxacin/metronidazole was superior to beta-lactam-based regimens for intra-abdominal infections (OR=1.69,95% CI 1.20-2.39) 5

• A randomized trial showed 96% clinical success rate with ciprofloxacin plus metronidazole in treating intra-abdominal infections 6

• Sequential IV-to-oral ciprofloxacin plus metronidazole therapy was statistically equivalent to ceftriaxone plus metronidazole for complicated intra-abdominal infections 7

Important Precautions

While these medications can be taken together, be aware of:

1. Spacing: Take ciprofloxacin at least 2 hours before or 6 hours after products containing magnesium, aluminum, calcium, iron, or zinc 4

2. Food interactions: Ciprofloxacin absorption may be delayed when taken with food 4

3. Alcohol: Avoid alcohol while taking metronidazole and for 24 hours afterward due to potential disulfiram-like reaction (nausea, vomiting, headache) 1

4. Side effects: Both medications can cause gastrointestinal disturbances; metronidazole can cause a metallic taste 1

5. Neurotoxicity risk: There is a risk of cumulative and potentially irreversible neurotoxicity with prolonged or repeated courses of metronidazole 2

Bottom Line

The combination of ciprofloxacin and metronidazole is not only safe but is a recommended treatment strategy for various mixed infections. Always take these medications as prescribed by your healthcare provider and complete the full course of treatment even if you begin feeling better before the medication is finished.