What are the best oral antibiotics for treating gonorrhea, chlamydia, and urinary tract infections (UTIs) in adult patients?

Best Oral Antibiotics for Gonorrhea, Chlamydia, and UTIs

Gonorrhea Treatment

For gonorrhea, cefixime 400 mg orally as a single dose is the best oral option, but it must always be combined with azithromycin 1 g orally for concurrent chlamydia coverage. 1, 2

Key Points on Oral Gonorrhea Treatment:

• Cefixime 400 mg orally achieves 97.4% cure rates for uncomplicated urogenital and anorectal gonorrhea, though this is lower than the 99.1% achieved with intramuscular ceftriaxone 1
• Fluoroquinolones (ciprofloxacin, ofloxacin) are no longer recommended due to widespread resistance, particularly in men who have sex with men and in geographic areas like California and Hawaii 1
• Always add azithromycin 1 g orally to any gonorrhea regimen to cover presumptive chlamydia coinfection 1
• Test-of-cure is mandatory at 1 week when using oral cefixime instead of intramuscular ceftriaxone 3, 4

Critical Caveat:

The CDC guidelines from 2006 1 represent the most recent formal guideline evidence, but they predate current resistance patterns. Cefixime availability has been intermittent, and declining susceptibility makes it less reliable than injectable ceftriaxone 4. If cefixime is unavailable or the patient has severe cephalosporin allergy, azithromycin 2 g orally as a single dose achieves 96-99% cure rates but causes significant gastrointestinal distress 2, 4.

---

Chlamydia Treatment

Doxycycline 100 mg orally twice daily for 7 days is the preferred treatment for chlamydia, achieving 98% cure rates. 1, 2

Treatment Options:

• Doxycycline 100 mg orally twice daily for 7 days is the first-line regimen with superior efficacy 1, 5
• Azithromycin 1 g orally as a single dose is an acceptable alternative with 97% cure rates and offers the advantage of directly observed single-dose therapy 1, 2
• Azithromycin is preferred when compliance is a concern or when directly observed therapy is needed 2

Important Considerations:

• Both regimens are equally effective for urogenital chlamydia 2
• Patients must abstain from sexual intercourse for 7 days after initiating single-dose therapy or until completing the 7-day regimen 2
• All sexual partners from the preceding 60 days must be evaluated and treated 2, 3

---

Urinary Tract Infections (UTIs)

For acute uncomplicated bacterial cystitis in otherwise healthy adult nonpregnant females, nitrofurantoin for 5 days is the recommended first-line oral antibiotic. 6

First-Line Oral Options:

• Nitrofurantoin (5-day course) is the preferred empiric treatment for uncomplicated UTIs 6
• Fosfomycin tromethamine 3 g as a single oral dose is an alternative first-line option 6
• Pivmecillinam (5-day course) is another first-line option where available 6

Second-Line Oral Options:

• Cephalexin or cefixime (oral cephalosporins) are second-line choices 6
• Fluoroquinolones should be reserved for cases where first-line agents cannot be used, due to high resistance rates in many communities 6
• Amoxicillin-clavulanate is a second-line β-lactam option 6

Critical Resistance Considerations:

• Trimethoprim-sulfamethoxazole and ciprofloxacin have high resistance rates in several communities and should not be used empirically, particularly in patients recently exposed to these antibiotics or at risk for ESBL-producing organisms 6
• For UTIs caused by ESBL-producing E. coli, oral options include nitrofurantoin, fosfomycin, pivmecillinam, amoxicillin-clavulanate, finafloxacin, and sitafloxacin 6
• For ESBL-producing Klebsiella pneumoniae UTIs, oral options are limited to pivmecillinam, fosfomycin, finafloxacin, and sitafloxacin 6

Common Pitfall to Avoid:

Do not use fluoroquinolones as first-line empiric therapy for UTIs unless local susceptibility data supports their use, as resistance rates have rendered them unreliable in many geographic areas 6. Knowledge of local antibiogram patterns is essential for appropriate empiric selection.

---

Combined STI Treatment Algorithm

When treating patients with suspected or confirmed gonorrhea and chlamydia coinfection:

1. Give cefixime 400 mg orally as a single dose PLUS azithromycin 1 g orally as a single dose 1, 2
2. If cefixime is unavailable or contraindicated, use azithromycin 2 g orally as a single dose (expect GI side effects) 2, 4
3. Instruct patients to abstain from sexual intercourse for 7 days after treatment initiation 2
4. Ensure all sexual partners from the preceding 60 days are evaluated and treated with the same dual therapy regimen 2, 3
5. Schedule test-of-cure at 1 week when using oral cefixime instead of intramuscular ceftriaxone 3, 4
6. Retest for reinfection at 3 months or at the first visit within 12 months after treatment 7