Can azithromycin (AZM) and ciprofloxacin (CIP) be taken together when treating a Sexually Transmitted Infection (STI)?

Azithromycin and Ciprofloxacin for STI Treatment

Azithromycin and ciprofloxacin should not be used together as a standard treatment regimen for STIs, as they are typically used as alternatives for different infections rather than in combination.

Treatment Recommendations by STI Type

Gonococcal Infections

• Ceftriaxone (125-250 mg IM in a single dose) is the preferred first-line treatment for gonococcal urethritis, cervix, and rectal infections 1, 2
• Ciprofloxacin (500 mg PO in a single dose) is listed as an alternative option, but should be used with caution due to increasing resistance 1, 2
• The CDC recommends dual therapy with ceftriaxone PLUS azithromycin for uncomplicated gonococcal infections to address possible chlamydial co-infection and combat antimicrobial resistance 2
• Quinolones (including ciprofloxacin) are no longer recommended as first-line therapy in many areas due to widespread resistance 1, 2

Non-gonococcal Urethritis

• Azithromycin (1 g PO in a single dose) is a recommended first-line treatment 1, 3
• Doxycycline (100 mg PO twice daily for 7 days) is an alternative first-line treatment 1, 3
• Levofloxacin (500 mg PO daily for 7 days) is another alternative option 1

Chlamydial Infections

• Azithromycin (1-1.5 g PO as a single dose) is recommended as first-line treatment 3, 4
• Doxycycline (100 mg PO twice daily for 7 days) is an effective alternative 3, 4

Evidence for Combined Use

• There is limited evidence supporting the simultaneous use of azithromycin and ciprofloxacin as a combination therapy for STIs 5
• A comparative trial showed that azithromycin 1g and ciprofloxacin 500mg as individual treatments (not combined) had similar efficacy for gonorrhea (96.0% vs 92.15% cure rates) 5

Important Considerations

Antimicrobial Resistance

• Quinolone-resistant N. gonorrhoeae is increasingly prevalent, limiting ciprofloxacin's utility 1, 2
• Azithromycin 1g alone is insufficient for gonorrhea treatment 2
• Dual therapy with two antimicrobials with different mechanisms of action is recommended to improve treatment efficacy and potentially delay emergence of resistance 2

Special Populations

• Pregnant women should not be treated with quinolones or tetracyclines 3, 2
• Men who have Sex with Men (MSM) should not receive quinolones due to higher prevalence of resistant strains 2

Side Effects

• When azithromycin is used at higher doses (2g) for gonorrhea, gastrointestinal side effects occur in approximately 35.3% of patients 6
• The combination of azithromycin and ciprofloxacin may potentially increase the risk of side effects, though specific data on this combination is limited

Clinical Decision Algorithm

1. Identify the specific STI pathogen(s) through appropriate testing

2. For gonococcal infections:

   • First choice: Ceftriaxone (125-250 mg IM) + Azithromycin (1g PO) 2
   • Alternative if cephalosporin allergy: Consider azithromycin 2g as single therapy 2
   • Ciprofloxacin should only be used if susceptibility is confirmed 1, 2

3. For non-gonococcal urethritis/chlamydial infections:

   • First choice: Azithromycin 1g PO single dose 1, 3
   • Alternative: Doxycycline 100mg PO twice daily for 7 days 1, 3

4. For suspected dual infection with both gonorrhea and chlamydia:

   • Use ceftriaxone for gonorrhea plus azithromycin for chlamydia 2
   • Do not use ciprofloxacin and azithromycin together unless specifically indicated by resistance patterns 1, 2