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.

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.

Neonatal infection treatment is typically started before the diagnosis of the cause can be confirmed.

Neonatal infection can be prophylactically treated with antibiotics. Maternal treatment with antibiotics is primarily used to protect against group B streptococcus.

Women with a history of HSV, can be treated with antiviral drugs to prevent symptomatic lesions and viral shedding that could infect the infant at birth. The antiviral medications used include acyclovir, penciclovir, valacyclovir, and famciclovir. Only very small amounts of the drug can be detected in the fetus. There are no increases in drug-related abnormalities in the infant that could be attributed to acyclovir. Long-term effects of antiviral medications have not been evaluated for their effects after growth and development of the child occurs. Neutropenia can be a complication of acyclovir treatment of neonatal HSV infection, but is usually transient. Treatment with immunoglobulin therapy has not been proven to be effective.

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.

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.

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.

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.

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.

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

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.

Note that, in neonates, sepsis is difficult to diagnose clinically. They may be relatively asymptomatic until hemodynamic and respiratory collapse is imminent, so, if there is even a remote suspicion of sepsis, they are frequently treated with antibiotics empirically until cultures are sufficiently proven to be negative. In addition to fluid resuscitation and supportive care, a common antibiotic regimen in infants with suspected sepsis is a beta-lactam antibiotic (usually ampicillin) in combination with an aminoglycoside (usually gentamicin) or a third-generation cephalosporin (usually cefotaxime—ceftriaxone is generally avoided in neonates due to the theoretical risk of kernicterus.) The organisms which are targeted are species that predominate in the female genitourinary tract and to which neonates are especially vulnerable to, specifically Group B Streptococcus, "Escherichia coli", and "Listeria monocytogenes" (This is the main rationale for using ampicillin versus other beta-lactams.) Of course, neonates are also vulnerable to other common pathogens that can cause meningitis and bacteremia such as "Streptococcus pneumoniae" and "Neisseria meningitidis". Although uncommon, if anaerobic species are suspected (such as in cases where necrotizing enterocolitis or intestinal perforation is a concern, clindamycin is often added.

Granulocyte-macrophage colony stimulating factor (GM-CSF) is sometimes used in neonatal sepsis. However, a 2009 study found that GM-CSF corrects neutropenia if present but it has no effect on reducing sepsis or improving survival.

Trials of probiotics for prevention of neonatal sepsis have generally been too small and statistically underpowered to detect any benefit, but a randomized controlled trial that enrolled 4,556 neonates in India reported that probiotics significantly reduced the risk of developing sepsis. The probiotic used in the trial was "Lactobacillus plantarum".

A very large meta-analysis investigated the effect of probiotics on preventing late-onset sepsis (LOS) in neonates. Probiotics were found to reduce the risk of LOS, but only in babies who were fed human milk exclusively. It is difficult to distinguish if the prevention was a result of the probiotic supplementation or if it was a result of the properties of human milk. It is also still unclear if probiotic administration reduces LOS risk in extremely low birth weight infants due to the limited number of studies that investigated it. Out of the 37 studies included in this systematic review, none indicated any safety problems related to the probiotics. It would be beneficial to clarify the relationship between probiotic supplementation and human milk for future studies in order to prevent late onset sepsis in neonates.

To reduce neonatal infection, routine screening of pregnant women for HIV, hepatitis B, syphilis, and rubella susceptibility is required in the UK.

Treatment with an vaginal antibiotic wash prior to birth does not prevent infection with group B streptococcus bacteria. Breast milk protects against necrotizing enterocolitis.

Because GBS bacteria can colonize the lower reproductive tract of 30% of women, typically pregnant women are tested for this pathogen from 35 to 37 weeks of pregnancy. Before delivery treatment of the mother with antibiotics reduces the rate of neonatal infection. Prevention of the infection of the baby is done by treating the mother with penicillin. Since the adoption of this prophylatic treatment, infant mortality from GBS infection has decreased by 80%.

Mothers with symptomatic HSV and who are treated with antiviral prophylaxis are less prone to have an active, symptomatic case at the time of birth and it may be able to reduce the risk of passing on HSV during birth. Cesarean delivery reduces the risk of infection of the infant.

Treatments of proven efficacy are currently limited mostly to herpes viruses and human immunodeficiency virus. The herpes virus is of two types: herpes type 1 (HSV-1, or oral herpes) and herpes type 2 (HSV-2, or genital herpes). Although there is no particular cure; there are treatments that can relieve the symptoms. Drugs like Famvir, Zovirax, and Valtrex are among the drugs used, but these medications can only decrease pain and shorten the healing time. They can also decrease the total number of outbreaks in the surrounding. Warm baths also may relive the pain of genital herpes.

Human Immunodeficiency Virus Infection (HIV) is treated by using a combination of medications to fight against the HIV infection in the body. This is called antiretroviral therapy (ART). ART is not a cure, but it can control the virus so that a person can live a longer, healthier life and reduce the risk of transmitting HIV to others around him. ART involves taking a combination of HIV medicines (called an HIV regimen) every day, exactly as prescribed by the doctor. These HIV medicines prevent HIV Virus from multiplying (making copies of itself in the body), which reduces the amount of HIV in the body. Having less HIV in the body gives the immune system a chance to recover and fight off infections and cancers. Even though there is still some HIV in the body, the immune system is strong enough to fight off infections and cancers. By reducing the amount of HIV in the body, HIV medicines also reduce the risk of transmitting the virus to others. ART is recommended for all people with HIV, regardless of how long they’ve had the virus or how healthy they are. If left untreated, HIV will attack the immune system and eventually progress to AIDS.

Development of new therapies has been hindered by the lack of appropriate animal model systems for some important viruses and also because of the difficulty in conducting human clinical trials for diseases that are rare. Nonetheless, numerous innovative approaches to antiviral therapy are available including candidate thiazolide and purazinecarboxamide derivatives with potential broad-spectrum antiviral efficacy. New herpes virus drugs include viral helicase-primase and terminase inhibitors. A promising new area of research involves therapies based on enhanced understanding of host antiviral immune responses.

Treatment is symptomatic and supportive. Children with hydrocephalus often need a ventriculoperitoneal shunt. Nucleoside analog ribavirin is used in some cases due to the inhibitory effect the agent has "in vitro" on arenaviruses. However, there is not sufficient evidence for efficacy in humans to support routine use. The only survivor of a transplant-associated LCMV infection was treated with ribavirin and simultaneous tapering of the immunosuppressive medications. Early and intravenous ribavirin treatment is required for maximal efficacy, and it can produce considerable side effects. Ribavirin has not been evaluated yet in controlled clinical trials.

Use of ribavirin during pregnancy is generally not recommended, as some studies indicate the possibility of teratogenic effects. If aseptic meningitis, encephalitis, or meningoencephalitis develops in consequence to LCMV, hospitalization and supportive treatment may be required. In some circumstances, anti-inflammatory drugs may also be considered. In general, mortality is less than one percent.

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.

Bacteremia should be treated for 2 weeks, meningitis for 3 weeks, and brain abscess for at least 6 weeks. Ampicillin generally is considered antibiotic of choice; gentamicin is added frequently for its synergistic effects. Overall mortality rate is 20–30%; of all pregnancy-related cases, 22% resulted in fetal loss or neonatal death, but mothers usually survive.

The main means of prevention is through the promotion of safe handling, cooking and consumption of food. This includes washing raw vegetables and cooking raw food thoroughly, as well as reheating leftover or ready-to-eat foods like hot dogs until steaming hot.

Another aspect of prevention is advising high-risk groups such as pregnant women and immunocompromised patients to avoid unpasteurized pâtés and foods such as soft cheeses like feta, Brie, Camembert cheese, and bleu. Cream cheeses, yogurt, and cottage cheese are considered safe. In the United Kingdom, advice along these lines from the Chief Medical Officer posted in maternity clinics led to a sharp decline in cases of listeriosis in pregnancy in the late 1980s.

Prognosis depends on the pathogen responsible for the infection and risk group. Overall mortality for "Candida" meningitis is 10-20%, 31% for patients with HIV, and 11% in neurosurgical cases (when treated). Prognosis for "Aspergillus" and coccidioidal infections is poor.

Recurring Mollaret meningitis attacks will occur through the patient lifespan so long as the HSV virus is not managed. Patients have reported symptoms for as long as 30 years from first episode. Diet and stress management are key to keeping the HSV virus at bay.

GBS is also an important infectious agent able to cause invasive infections in adults. Serious life-threatening invasive GBS infections are increasingly recognized in the elderly and in individuals compromised by underlying diseases such as diabetes, cirrhosis and cancer. GBS infections in adults include urinary tract infection, skin and soft-tissue infection (skin and skin structure infection) bacteremia without focus, osteomyelitis, meningitis and endocarditis.

GBS infection in adults can be serious, and mortality is higher among adults than among neonates.

In general, penicillin is the antibiotic of choice for treatment of GBS infections. Erythromycin or clindamycin should not be used for treatment in penicillin-allergic patients unless susceptibility of the infecting GBS isolate to these agents is documented. Gentamicin plus penicillin (for antibiotic synergy) in patients with life-threatening GBS infections may be used.

Treatment options in persons without HIV-infection have not been well studied. Intravenous Amphotericin B combined with flucytosine by mouth is recommended.

Persons living with AIDS often have a greater burden of disease and higher mortality (30-70% at 10-weeks), but recommended therapy is with amphotericin B and flucytosine. Where flucytosine is not available (many low and middle income countries), fluconazole should be used with amphotericin. Amphotericin-based induction therapy has much greater microbiologic activity than fluconazole monotherapy with 30% better survival at 10-weeks. Based on a systematic review of existing data, the most cost-effective induction treatment in resource-limited settings appears to be one week of amphotericin B coupled with high-dose fluconazole. After initial induction treatment as above, typical consolidation therapy is with oral fluconazole for at least 8 weeks used with secondary prophylaxis with fluconazole thereafter.

The decision on when to start treatment for HIV appears to be very different than other opportunistic infections. A large multi-site trial supports deferring ART for 4–6 weeks was overall preferable with 15% better 1-year survival than earlier ART initiation at 1–2 weeks after diagnosis. A Cochrane review also supports the delayed starting of treatment until cryptococcosis starts improving with antifungal treatment.

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.