Viral meningitis typically only requires supportive therapy; most viruses responsible for causing meningitis are not amenable to specific treatment. Viral meningitis tends to run a more benign course than bacterial meningitis. Herpes simplex virus and varicella zoster virus may respond to treatment with antiviral drugs such as aciclovir, but there are no clinical trials that have specifically addressed whether this treatment is effective. Mild cases of viral meningitis can be treated at home with conservative measures such as fluid, bedrest, and analgesics.

Additional treatment with corticosteroids (usually dexamethasone) has shown some benefits, such as a reduction of hearing loss, and better short term neurological outcomes in adolescents and adults from high-income countries with low rates of HIV. Some research has found reduced rates of death while other research has not. They also appear to be beneficial in those with tuberculosis meningitis, at least in those who are HIV negative.

Professional guidelines therefore recommend the commencement of dexamethasone or a similar corticosteroid just before the first dose of antibiotics is given, and continued for four days. Given that most of the benefit of the treatment is confined to those with pneumococcal meningitis, some guidelines suggest that dexamethasone be discontinued if another cause for meningitis is identified. The likely mechanism is suppression of overactive inflammation.

Additional treatment with corticosteroids have a different role in children than in adults. Though the benefit of corticosteroids has been demonstrated in adults as well as in children from high-income countries, their use in children from low-income countries is not supported by the evidence; the reason for this discrepancy is not clear. Even in high-income countries, the benefit of corticosteroids is only seen when they are given prior to the first dose of antibiotics, and is greatest in cases of "H. influenzae" meningitis, the incidence of which has decreased dramatically since the introduction of the Hib vaccine. Thus, corticosteroids are recommended in the treatment of pediatric meningitis if the cause is "H. influenzae", and only if given prior to the first dose of antibiotics; other uses are controversial.

Treatment for meningitis is antibiotics. The particular drugs used are based off the infecting bacteria, but a mix of ampicillin, gentamicin, and cefotaxime is used for early-onset meningitis before identification of infection. A regimen of antistaphylococcal antibiotic, such as nafcillin or vancomycin, plus cefotaxime or ceftazidime with or without an aminoglycoside is recommended for late-onset neonatal meningitis. The aim for these treatments is to sterilize the CSF of any meningitis-causing pathogens. A repeated LP 24–48 hours after initial treatment should be used to declare sterilization.

In cases of herpes simplex virus-derived meningitis, antiviral therapy (acyclovir or vidarabine) must be started immediately for a favorable outcome. Acyclovir is a better antiviral because it shows a similar effect on the infection as vidarabine and is safer to use in the neonate. The recommended dosage is 20 mg/kg every six hours for 21 days.

Because it is a bacterial disease, the primary method of treatment for "Haemophilus" meningitis is anti-bacterial therapy. Common antibiotics include ceftriaxone or cefotaxime, both of which can combat the infection and thus reduce inflammation in the meninges, or the membranes that protect the brain and spinal cord. Anti-inflammatories such as corticosteroids, or steroids produced by the body to reduce inflammation, can also be used to fight the meningeal inflammation in an attempt to reduce risk of mortality and reduce the possibility of brain damage.

When meningococcal disease is suspected, treatment must be started "immediately" and should not be delayed while waiting for investigations. Treatment in primary care usually involves prompt intramuscular administration of benzylpenicillin, and then an urgent transfer to hospital (hopefully, an academic level I medical center, or at least a hospital with round the clock neurological care, ideally with neurological intensive and critical care units) for further care. Once in the hospital, the antibiotics of choice are usually IV broad spectrum 3rd generation cephalosporins, e.g., cefotaxime or ceftriaxone. Benzylpenicillin and chloramphenicol are also effective. Supportive measures include IV fluids, oxygen, inotropic support, e.g., dopamine or dobutamine and management of raised intracranial pressure. Steroid therapy may help in some adult patients, but is unlikely to affect long term outcomes.

Complications following meningococcal disease can be divided into early and late groups. Early complications include: raised intracranial pressure, disseminated intravascular coagulation, seizures, circulatory collapse and organ failure. Later complications are: deafness, blindness, lasting neurological deficits, reduced IQ, and gangrene leading to amputations.

The treatment of TB meningitis is isoniazid, rifampicin, pyrazinamide and ethambutol for two months, followed by isoniazid and rifampicin alone for a further ten months. Steroids help reduce the risk of death in those without HIV. Steroids can be used in the first six weeks of treatment, A few people may require immunomodulatory agents such as thalidomide. Hydrocephalus occurs as a complication in about a third of people with TB meningitis. The addition of aspirin may reduce or delay mortality, possibly by reducing complications such as infarcts.

Throughout history treatment relied primarily on β-lactam antibiotics. In the 1960s nearly all strains of "S. pneumoniae" were susceptible to penicillin, but more recently there has been an increasing prevalence of penicillin resistance especially in areas of high antibiotic use. A varying proportion of strains may also be resistant to cephalosporins, macrolides (such as erythromycin), tetracycline, clindamycin and the quinolones. Penicillin-resistant strains are more likely to be resistant to other antibiotics. Most isolates remain susceptible to vancomycin, though its use in a β-lactam-susceptible isolate is less desirable because of tissue distribution of the drug and concerns of development of vancomycin resistance. More advanced beta-lactam antibiotics (cephalosporins) are commonly used in combination with other drugs to treat meningitis and community-acquired pneumonia. In adults recently developed fluoroquinolones such as levofloxacin and moxifloxacin are often used to provide empiric coverage for patients with pneumonia, but in parts of the world where these drugs are used to treat tuberculosis resistance has been described.

Susceptibility testing should be routine with empiric antibiotic treatment guided by resistance patterns in the community in which the organism was acquired. There is currently debate as to how relevant the results of susceptibility testing are to clinical outcome. There is slight clinical evidence that penicillins may act synergistically with macrolides to improve outcomes.

"Haemophilus influenzae" produces beta-lactamases, and it is also able to modify its penicillin-binding proteins, so it has gained resistance to the penicillin family of antibiotics.

In severe cases, cefotaxime and ceftriaxone delivered directly into the bloodstream are the elected antibiotics, and, for the less severe cases, an association of ampicillin and sulbactam, cephalosporins of the second and third generation, or fluoroquinolones are preferred. (Fluoroquinolone-resistant "Haemophilus influenzae" have been observed.)

Macrolide antibiotics (e.g., clarithromycin) may be used in patients with a history of allergy to beta-lactam antibiotics. Macrolide resistance has also been observed.

The serious complications of HiB are brain damage, hearing loss, and even death.

Treatment is generally supportive. Rest, hydration, antipyretics, and pain or anti-inflammatory medications may be given as needed.

Herpes simplex virus, varicella zoster virus and cytomegalovirus have a specific antiviral therapy. For herpes the treatment of choice is aciclovir.

Surgical management is indicated where there is extremely increased intracranial pressure, infection of an adjacent bony structure (e.g. mastoiditis), skull fracture, or abscess formation.

The majority of people that have viral meningitis get better within 7-10 days.

Children 2–10 years of age who are at high risk for meningococcal disease such as certain chronic medical conditions and travel to or reside in countries with hyperendemic or epidemic meningococcal disease should receive primary immunization. Although safety and efficacy of the vaccine have not been established in children younger than 2 years of age and under outbreak control, the unconjugated vaccine can be considered.

Antibiotics are the treatment of choice for bacterial pneumonia, with ventilation (oxygen supplement) as supportive therapy. The antibiotic choice depends on the nature of the pneumonia, the microorganisms most commonly causing pneumonia in the geographical region, and the immune status and underlying health of the individual. In the United Kingdom, amoxicillin is used as first-line therapy in the vast majority of patients acquiring pneumonia in the community, sometimes with added clarithromycin. In North America, where the "atypical" forms of community-acquired pneumonia are becoming more common, clarithromycin, azithromycin, or fluoroquinolones as single therapy have displaced the amoxicillin as first-line therapy.

Local patterns of antibiotic-resistance always need to be considered when initiating pharmacotherapy. In hospitalized individuals or those with immune deficiencies, local guidelines determine the selection of antibiotics.

Before the widespread use of the Hib vaccine, "Haemophilus" meningitis accounted for 40%-60% of all meningitis cases in children under the age of fifteen, and 90% of all meningitis cases in children under the age of five. Vaccination can reduce incidence. Vaccination has reduced the occurrences of "Haemophilus" meningitis by 87-90% in countries with widespread access to the Hib vaccine. Rates are still high in areas with limited levels of vaccination. Less-developed countries as well as countries with medical infrastructure that has been damaged in any way, such as from warfare, do not have such widespread access to the vaccine and thus experience higher rates of meningitis cases. Multiple conjugate Hib vaccines are available for use, though, and are extremely effective when given to infants. Additionally, the vaccine has only the side effects of reddened skin and swelling at the location of the injection.

Neuraminidase inhibitors may be used to treat viral pneumonia caused by influenza viruses (influenza A and influenza B). No specific antiviral medications are recommended for other types of community acquired viral pneumonias including SARS coronavirus, adenovirus, hantavirus, and parainfluenza virus. Influenza A may be treated with rimantadine or amantadine, while influenza A or B may be treated with oseltamivir, zanamivir or peramivir. These are of most benefit if they are started within 48 hours of the onset of symptoms. Many strains of H5N1 influenza A, also known as avian influenza or "bird flu", have shown resistance to rimantadine and amantadine. The use of antibiotics in viral pneumonia is recommended by some experts, as it is impossible to rule out a complicating bacterial infection. The British Thoracic Society recommends that antibiotics be withheld in those with mild disease. The use of corticosteroids is controversial.

Antibiotics improve outcomes in those with bacterial pneumonia. Antibiotic choice depends initially on the characteristics of the person affected, such as age, underlying health, and the location the infection was acquired. In the UK, treatment before culture results with amoxicillin is recommended as the first line for community-acquired pneumonia, with doxycycline or clarithromycin as alternatives. In North America, where the "atypical" forms of community-acquired pneumonia are more common, macrolides (such as azithromycin or erythromycin), and doxycycline have displaced amoxicillin as first-line outpatient treatment in adults. In children with mild or moderate symptoms, amoxicillin remains the first line. The use of fluoroquinolones in uncomplicated cases is discouraged due to concerns about side-effects and generating resistance in light of there being no greater clinical benefit.

For those who require hospitalization and caught their pneumonia in the community the use of a β-lactam such as cephazolin plus macrolide such as azithromycin or a fluoroquinolones is recommended. The addition of corticosteroids also appears to improve outcomes.

The duration of treatment has traditionally been seven to ten days, but increasing evidence suggests that shorter courses (three to five days) are similarly effective. Recommendations for hospital-acquired pneumonia include third- and fourth-generation cephalosporins, carbapenems, fluoroquinolones, aminoglycosides, and vancomycin. These antibiotics are often given intravenously and used in combination. In those treated in hospital, more than 90% improve with the initial antibiotics.

"Streptococcus pneumoniae" — amoxicillin (or erythromycin in patients allergic to penicillin); cefuroxime and erythromycin in severe cases.

"Staphylococcus aureus" — flucloxacillin (to counteract the organism's β-lactamase).

Fungal meningitis is treated with long courses of high dose antifungal medications. The duration of treatment is dependent upon the causal pathogen and the patient's ability to stave off the infection; for patients with a weaker immune system or diabetes, treatment will often take longer.

If the tonsillitis is caused by group A streptococcus, then antibiotics are useful, with penicillin or amoxicillin being primary choices. Cephalosporins and macrolides are considered good alternatives to penicillin in the acute setting. A macrolide such as erythromycin is used for people allergic to penicillin. Individuals who fail penicillin therapy may respond to treatment effective against beta-lactamase producing bacteria such as clindamycin or amoxicillin-clavulanate. Aerobic and anaerobic beta lactamase producing bacteria that reside in the tonsillar tissues can "shield" group A streptococcus from penicillins.

It is extremely difficult to successfully treat BPF, mainly because of the difficulty obtaining a proper diagnosis. Since the disease starts out with what seems to be a common case of conjunctivitis, "H. aegyptius" is not susceptible to the antibiotic eye drops that are being used to treat it. This treatment is ineffective because it treats only the local ocular infection, whereas if it progresses to BPF, systemic antibiotic treatment is required. Although BPF is susceptible to many commonly used antibiotics, including ampicillin, cefuroxime, cefotaxime, rifampin, and chloramphenicol, by the time it is diagnosed the disease has progressed too much to be effectively treated. However, with the fast rate of progression of BPF it is unlikely that it will be successfully treated. With antibiotic therapy, the mortality rate of BPF is around 70%.

Chronic cases may be treated with tonsillectomy (surgical removal of tonsils) as a choice for treatment. Children have had only a modest benefit from tonsillectomy for chronic cases of tonsillitis.

Antiviral therapy: as early as possible

10~15mg/kg every 8 hours for 14~21d

5~10mg/kg every 12hours for 14~21d

immune therapy: interferon

symptomatic therapy

High fever: physical regulation of body temperature

Seizure: antiepileptic drugs

high intracranial pressure-20%mannitol

Infections: antibiotic drugs

In addition, people should be given antibiotics, such as second- or third-generation cephalosporins, either alone or in combination with penicillin or ampicillin for streptococcal coverage. If allergy to penicillins is present, Co-trimoxazole or clindamycin is an alternative.

Acyclovir is the treatment of choice for Mollaret's meningitis. Some patients see a drastic difference in how often they get sick and others don't. Often treatment means managing symptoms, such as pain management and strengthening the immune system.

The IHMF recommends that patients with benign recurrent lymphocytic meningitis receive intravenous acyclovir in the amount of 10 mg/kg every 8 hours, for 14–21 days. More recently, the second-generation antiherpetic drugs valacyclovir and famciclovir have been used to successfully treat patients with Mollaret's. Additionally, it has been reported that Indomethacin administered in the amount of 25 mg 3 times per day after meals, or 50 mg every 4 hours, has resulted in a faster recovery for patients, as well as more extended symptom-free intervals, between episodes.

The Hib vaccine is very effective at preventing the disease.

In household contacts of any unvaccinated child infected with H. influenzae, rifampicin is used as prophylaxis.