What antibiotics are used to treat prostatitis?

Antibiotic Treatment for Prostatitis

Acute Bacterial Prostatitis

For acute bacterial prostatitis, ciprofloxacin 500-750 mg orally twice daily for 2-4 weeks is the first-line treatment when local fluoroquinolone resistance is below 10%, with a 92-97% success rate. 1, 2

Outpatient Oral Therapy (Mild to Moderate Cases)

• Ciprofloxacin 500-750 mg orally twice daily for 2-4 weeks is the preferred first-line agent 1, 2
• Levofloxacin 750 mg orally once daily is an alternative fluoroquinolone option 3, 1
• Local resistance patterns must guide selection—fluoroquinolone resistance should be <10% for empiric use 4, 1

Inpatient IV Therapy (Severe Cases, Fever, Systemic Toxicity)

• Ceftriaxone 1-2 g IV once daily or cefotaxime 2 g IV three times daily are first-choice parenteral options 3, 1
• Ciprofloxacin 400 mg IV twice daily can be used parenterally, transitioning to oral once clinically improved 4, 1
• Piperacillin-tazobactam 2.5-4.5 g IV three times daily is effective for broad-spectrum coverage 3, 2
• Amikacin 15 mg/kg IV once daily is a second-choice option for severe cases 1
• Hospitalization is indicated for patients unable to tolerate oral medications, those at risk for urosepsis (occurs in 7.3% of cases), or those with fever and systemic toxicity 4, 1

Treatment Duration and Monitoring

• Total antibiotic duration is 2-4 weeks to prevent progression to chronic bacterial prostatitis 4, 1
• Assess clinical response after 48-72 hours of treatment 4
• Critical pitfall: Stopping antibiotics prematurely leads to chronic bacterial prostatitis 1

Special Considerations

• Avoid amoxicillin or ampicillin empirically due to very high worldwide resistance rates 1
• For healthcare-associated infections with enterococci, use ampicillin, piperacillin-tazobactam, or vancomycin based on susceptibility 4
• Consider carbapenems or novel broad-spectrum agents only when early culture results indicate multidrug-resistant organisms 3, 4
• Never perform prostatic massage in acute bacterial prostatitis due to risk of bacteremia 4, 1

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Chronic Bacterial Prostatitis

For chronic bacterial prostatitis, levofloxacin 500 mg orally once daily or ciprofloxacin 500 mg orally twice daily for a minimum of 4 weeks (up to 2-3 months) is first-line therapy. 1, 5, 6

First-Line Fluoroquinolone Therapy

• Levofloxacin 500 mg orally once daily for 28 days minimum 1, 5, 6
  • FDA-approved for chronic bacterial prostatitis with 75% microbiologic eradication rate 5
  • Clinical success rates: 92% at 5-12 days, 77.4% at 1 month, 66% at 3 months, 61.9% at 6 months 6
• Ciprofloxacin 500 mg orally twice daily for 28 days minimum 1, 5, 7
  • FDA-approved with 76.8% microbiologic eradication rate 5
  • Achieves prostatic tissue penetration ratios up to 4:1 (prostate:serum) 6

Why Fluoroquinolones Are Preferred

• Fluoroquinolones become trapped in chronically inflamed prostate tissue due to pH differences between prostatic tissue and serum, achieving high prostatic concentrations 6, 8
• Ciprofloxacin and levofloxacin produce the highest concentrations in prostatic tissue among available antibiotics 8
• Penicillins, cephalosporins, and aminoglycosides do NOT penetrate well into chronically inflamed prostate tissue and should be avoided 9

Extended Duration Therapy

• Therapy should be continued for 2-3 months in refractory cases 9
• The longer duration addresses the relative impermeability of the non-inflamed prostate to antimicrobials 9

Atypical Pathogens (Chlamydia, Mycoplasma)

• Test for atypical pathogens including Chlamydia trachomatis and Mycoplasma species, which require specific antimicrobial therapy 1, 10
• Doxycycline 100 mg orally twice daily for 7 days or azithromycin 1 g orally single dose for confirmed Chlamydia or Mycoplasma 1
• Doxycycline has the advantage of activity against chlamydia as well as usual gram-negative organisms 9

Diagnostic Confirmation

• The Meares-Stamey 4-glass test or simplified 2-specimen variant confirms chronic bacterial prostatitis, requiring a 10-fold higher bacterial count in expressed prostatic secretions than midstream urine 1, 10
• Culture and sensitivity testing should guide final antibiotic selection 10
• Follow-up cultures may be necessary to confirm eradication 10

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Key Causative Organisms

Acute Bacterial Prostatitis

• Gram-negative bacteria cause 80-97% of cases: E. coli, Klebsiella pneumoniae, Pseudomonas aeruginosa 4, 2
• Gram-positive bacteria: Staphylococcus aureus, Enterococcus species, Group B streptococci 4

Chronic Bacterial Prostatitis

• Up to 74% are due to gram-negative organisms, particularly E. coli 4, 2
• Other pathogens: Proteus mirabilis, Enterobacter species, Serratia marcescens 4
• Enterococcus faecalis and methicillin-susceptible Staphylococcus epidermidis 5

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Critical Pitfalls to Avoid

• Never use oral cephalosporins (e.g., cefpodoxime) for prostatitis—they have poor prostatic tissue penetration despite efficacy in pyelonephritis 4
• Never perform prostatic massage in acute bacterial prostatitis—this causes bacteremia 4, 1
• Never stop antibiotics prematurely—this leads to chronic bacterial prostatitis 1
• Never use penicillins, cephalosporins, or aminoglycosides for chronic bacterial prostatitis—they do not penetrate chronically inflamed prostate tissue 9
• Always check local fluoroquinolone resistance patterns—empiric use requires <10% resistance 4, 1