What is the treatment for meningitis?

Treatment of Meningitis

Start empiric antibiotic therapy immediately upon clinical suspicion of bacterial meningitis—within 1 hour of hospital arrival—even before lumbar puncture or imaging is performed, as delays in treatment are strongly associated with death and poor outcomes. 1

Immediate Management Algorithm

Step 1: Obtain Blood Cultures and Start Antibiotics

• Draw blood cultures immediately upon suspicion of meningitis 1
• Do not delay antibiotics for lumbar puncture or CT imaging 1
• Antibiotic administration should occur within 60 minutes of hospital presentation 1

Step 2: Determine Need for Pre-LP Imaging

Perform cranial CT before lumbar puncture ONLY if the patient has: 1

• Focal neurologic deficits (excluding cranial nerve palsies)
• New-onset seizures
• Severely altered mental status (Glasgow Coma Scale <10)
• Severely immunocompromised state

If any of these are present, start empiric antibiotics immediately before imaging 1

Step 3: Select Empiric Antibiotic Regimen Based on Age

Adults <60 years:

• Ceftriaxone 2g IV every 12 hours (or cefotaxime 2g IV every 6 hours) 1
• PLUS Vancomycin 15-20 mg/kg IV every 8-12 hours (target trough 15-20 μg/mL) 1
• Add vancomycin empirically due to potential pneumococcal resistance 2

Adults ≥60 years:

• Ceftriaxone 2g IV every 12 hours (or cefotaxime 2g IV every 6 hours) 1
• PLUS Vancomycin 15-20 mg/kg IV every 8-12 hours 1
• PLUS Ampicillin 2g IV every 4 hours (for Listeria coverage) 1

Neonates <1 month:

• Ampicillin 50 mg/kg IV every 6-8 hours 1
• PLUS Cefotaxime 50 mg/kg IV every 6-8 hours 1
• Administer IV doses over 60 minutes in neonates to reduce bilirubin encephalopathy risk 3

Children 1 month to 18 years:

• Ceftriaxone 50 mg/kg IV every 12 hours (maximum 2g every 12 hours) 1
• PLUS Vancomycin 10-15 mg/kg IV every 6 hours (target trough 15-20 μg/mL) 1

Step 4: Add Adjunctive Dexamethasone

• Dexamethasone 10 mg IV every 6 hours should be started with or just before the first antibiotic dose in adults with suspected pneumococcal meningitis 1, 4
• Continue for 4 days if pneumococcal meningitis is confirmed 1
• Dexamethasone improves outcomes in pneumococcal meningitis but may reduce vancomycin CSF penetration 1

Pathogen-Specific Definitive Therapy

Streptococcus pneumoniae (Pneumococcal Meningitis)

If penicillin-sensitive (MIC ≤0.06 mg/L):

• Continue ceftriaxone 2g IV every 12 hours for 10-14 days 1
• Alternative: benzylpenicillin 2.4g IV every 4 hours 1

If penicillin-resistant but cephalosporin-sensitive:

• Continue ceftriaxone 2g IV every 12 hours for 10-14 days 1

If both penicillin and cephalosporin-resistant:

• Ceftriaxone 2g IV every 12 hours 1
• PLUS Vancomycin 15-20 mg/kg IV every 12 hours 1
• PLUS Rifampicin 600 mg IV/PO every 12 hours 1
• Treat for 14 days 1
• Consider repeat LP at 48-72 hours to document CSF sterilization 1

Duration: 10 days if clinically recovered; extend to 14 days if slow to respond or resistant organism 1

Neisseria meningitidis (Meningococcal Meningitis)

• Ceftriaxone 2g IV every 12 hours for 5 days 1
• Alternative: benzylpenicillin 2.4g IV every 4 hours 1
• Add single dose ciprofloxacin 500 mg PO if NOT treated with ceftriaxone (to eliminate throat carriage) 1

Duration: 5 days if clinically recovered 1

Listeria monocytogenes

• Ampicillin 2g IV every 4 hours for 21 days 1
• Alternative: co-trimoxazole 10-20 mg/kg (trimethoprim component) IV in 4 divided doses 1
• Do NOT use cephalosporins alone—they have no activity against Listeria 1, 5

Haemophilus influenzae

• Ceftriaxone 2g IV every 12 hours for 10 days 1
• Alternative: moxifloxacin 400 mg IV daily 1

Gram-Negative Bacilli (Enterobacteriaceae)

• Ceftriaxone 2g IV every 12 hours for 21 days 1
• Consider adding aminoglycoside in neonates or severe cases 1, 5
• Be alert for ESBL-producing organisms in patients with recent travel or healthcare exposure 1

Special Situations

Viral Meningitis (Post-Varicella/VZV)

• Aciclovir 10-15 mg/kg IV every 8 hours for 10-14 days 6
• Consider adding corticosteroids (prednisolone 60-80 mg daily for 3-5 days) if vasculitic component suspected 6

Penicillin Allergy

• Chloramphenicol 25 mg/kg IV every 6 hours as alternative to beta-lactams 1

Outpatient Parenteral Antibiotic Therapy (OPAT)

Consider OPAT for patients who: 1

• Are afebrile and clinically improving
• Have received ≥5 days inpatient therapy
• Have reliable IV access
• Can access 24-hour medical care

OPAT regimen: Ceftriaxone 2g IV twice daily initially; may switch to 4g IV once daily after first 24 hours 1

Critical Pitfalls to Avoid

1. Never delay antibiotics for imaging or LP—mortality increases with each hour of delay 1

2. Never use cephalosporins alone in patients ≥60 years—must add ampicillin for Listeria coverage 1

3. Never omit vancomycin from empiric therapy—pneumococcal resistance remains a concern despite declining prevalence 2

4. Never use vancomycin as monotherapy—CSF penetration is inadequate, especially with dexamethasone 1

5. Never stop antibiotics prematurely—complete the full course even if rapid clinical improvement occurs 1

6. Never assume penicillin sensitivity—up to 80% of meningococcal strains may have reduced susceptibility in some regions 7

7. Never use first-generation cephalosporins—they achieve inadequate CSF concentrations and have high failure rates 8, 9