Ciprofloxacin (Cipro®) vs Azithromycin (Zithromax®)

Based on "Antibiotic and Chemotherapy"
written by Roger G. Finch

Ciprofloxacin vs Azithromycin for Traveler's diarrhea

Ciprofloxacin is the drug of first choice for traveler's diarrhea. However, in several regions there are high levels of resistance to fluoroquinolones among Campylobacter species and other enteropathogenic bacteria.

A growing body of evidence supports the use of short-course ciprofloxacin in the treatment of traveler's diarrhea in children.

Ciprofloxacin dosage for Traveler's diarrhea:
500 mg twice daily for 1-3 days. According to results of many clinical trials a single dose of antibiotic is generally effective. However, for severe diarrhea 3-days antibiotic therapy is more effective.

Azithromycin is an alternative choice for the treatment of traveler's diarrhea. It is an important medication for traveler's diarrhea in areas with fluoroquinolone resistant Campylobacter species. Azithromycin is effective against Campylobacter species and the broad range of bacteria that cause traveler's diarrhea. Also, azithromycin is a suitable safe choice for children and pregnant women.

Azithromycin dosage for Traveler's diarrhea:
500 mg daily for one to three days or 1,000 mg as a single dose.

Shigellosis

Ciprofloxacin is somewhat more effective than azithromycin in the treatment of Shigellosis (a type of infective diarrhea) 3.

Results of randomized, double-blind comparison of azithromycin and ciprofloxacin for shigellosis 3.	Ciprofloxacin	Azithromycin
Regimen	500 mg every 12 hours for 5 days.	500 mg on day 1, followed by 250 mg once daily for 4 days
Clinical success rate	32 (89%) patients	28 (82%) patients
Bacteriologic success rate	36 (100%) patients	32 (94%) patients

Ciprofloxacin vs Azithromycin for UTI

Most urinary tract infections represent acute uncomplicated cystitis. E. coli is the predominant pathogen in uncomplicated UTIs.

Currently, neither ciprofloxacin nor azithromycin are the first line antibiotics for UTIs. In other words, these drugs are not the best, mainly because of growing bacterial resistance to these antibiotics.

Ciprofloxacin is approved by the FDA for the treatment urinary tract infections. Ciprofloxacin may be used in situations, when first line drugs (fosfomycin, nitrofurantoin, and trimethoprim/sulfamethoxazole) cannot be used.

Azithromycin is not indicated for UTIs. Azithromycin may be used to treat urinary problems secondary to sexually transmitted infections.

Azithromycin and ciprofloxacin combination therapy holds promise against biofilm-associated UTIs as it confers antibacterial, immunomodulatory and anti-inflammatory effects1.

Ciprofloxacin vs Azithromycin for Chronic prostatitis

Azithromycin is significantly more effective than ciprofloxacin in the treatment of chronic prostatitis caused by Chlamydia trachomatis.

Results of comparative analysis of azithromycin and ciprofloxacin for chronic prostatitis caused by C. trachomatis 2.	Ciprofloxacin	Azithromycin
Regimen	500 mg b.i.d. for 20 days	500 mg 3 times per week for 3 weeks
Bacterial eradication rate	17 of 44 patients	36 of 45 patients
Clinical cure rate	15 of 44 patients	31 of 45 patients

Ciprofloxacin vs Azithromycin for Gonorrhea

Azithromycin is at least as effective and well tolerated as ciprofloxacin in the treatment of gonococcal infections 4.

Results of single-blind comparative study of azithromycin and ciprofloxacin for gonorrhea 4.	Ciprofloxacin	Azithromycin
Regimen	single 500 mg dose	single 1 g dose
Clinical and microbiological cure rates after 2 weeks	92.15% (47 out of 51)	96.0% (48 out of 50)

Ciprofloxacin	Azithromycin
Brand names
• Cipro® • Cipro XR® • ProQuin XR®	• Zithromax® • Z-PAK®
Drug class
• Antibiotic
• Fluoroquinolone	• Macrolide
Dose formulations
• Tablets • Tablets, extended release • Oral suspension • Injection	• Tablets • Capsules • Powder for solution • Oral suspension
FDA-approved indications
• Sinusitis • Community-acquired pneumonia • Acute exacerbations of chronic bronchitis • Skin and skin structure infections
• Urinary tract infections (cystitis, pyelonephritis) • Bacterial prostatitis • Infectious diarrhea • Gonococcal infections • and many other indications	• Acute otitis media • Pharyngitis/tonsillitis • Urethritis and cervicitis • Chancroid
"Off-label" uses
• Traveler’s diarrhea • Cat scratch disease
• Pelvic inflammatory disease	• Pertussis • Gonococcal infections • Lyme disease
Mechanism of action
• Bactericidal • Ciprofloxacin inhibits bacterial DNA synthesis. Promotes breakage of double-stranded DNA.	• Bacteriostatic • Azithromycin inhibits bacterial protein synthesis.
Half-life
• 4 hours	• 40 hours
Oral bioavailability
• 50-85%	• 37%
Metabolism, Elimination
• Ciprofloxacin is eliminated mainly by renal excretion. • The drug is also metabolized and partially eliminated in the bile.	• Excreted billiary, mainly as unchanged drug in the feces. Urinary excretion is about 6%.
Contraindications
• Allergy to ciprofloxacin or other quinolones. • Concomitant use with tizanidine.	• Allergy to macrolide or ketolide antibiotics. • History of hepatic dysfunction associated with prior use of azithromycin.
Side effects
• Nausea • Abdominal pain • Diarrhea • Increased aminotransferase levels • Vomiting • Rash • Tendinitis and tendon rupture • CNS disturbances	• Diarrhea • Nausea • Abdominal pain • Vomiting • Dyspepsia
Pregnancy category
C	B • Azithromycin is safe for use in children and pregnant women.

References

1. Saini H, Chhibber S, Harjai K. Azithromycin and ciprofloxacin: a possible synergistic combination against Pseudomonas aeruginosa biofilm-associated urinary tract infections. Int J Antimicrob Agents. 2015 Apr;45(4):359-67
2. Skerk V, Schonwald S, Krhen I, Banaszak A, Begovac J, Strugar J, Strapac Z, Vrsalovic R, Vukovic J, Tomas M. Comparative analysis of azithromycin and ciprofloxacin in the treatment of chronic prostatitis caused by Chlamydia trachomatis. Int J Antimicrob Agents. 2003 May;21(5):457-62. PubMed
3. Khan WA, Seas C, Dhar U, Salam MA, Bennish ML. Treatment of shigellosis: V. Comparison of azithromycin and ciprofloxacin. A double-blind, randomized, controlled trial. Ann Intern Med. 1997 May 1;126(9):697-703. PubMed
4. Gruber F, Brajac I, Jonjic A, Grubisic-Greblo H, Lenkovic M, Stasic A. Comparative trial of azithromycin and ciprofloxacin in the treatment of gonorrhea. J Chemother. 1997 Aug;9(4):263-6. PubMed