There has been no specific drug therapy developed for hepatitis, with the exception of hepatitis C. Patients are advised to rest in the early stages of the illness, and to eat small, high-calorie, high-protein meals in order to battle anorexia. Larger meals are more easily tolerated in the morning, for patients often experience nausea later in the day. Although high-protein meals are recommended, protein intake should be reduced if signs of precoma — lethargy, confusion, and mental changes — develop.

In acute viral hepatitis, hospitalization is usually required only for patients with severe symptoms (severe nausea, vomiting, change in mental status, and PT greater than 3 seconds above normal) or complications. If the patient experiences continuous vomiting and is unable to maintain oral intake, parenteral nutrition may be required.

In order to relieve nausea and also prevent vomiting, antiemetics (diphenhydramine or prochlorperazine) may be given 30 minutes before meals. However, phenothiazines have a cholestatic effect and should be avoided. The resin cholestyramine may be given only for severe pruritus.

Some cases of viral hepatitis cannot be ascribed to hepatitis A, B, C, D, or E, so they are called non A...E hepatitis, or hepatitis X. During the diagnostic process for hepatitis X, the possible alternative diagnoses should be considered: hepatitis A, B, C, D, and E, and CMV (Cytomegalovirus).

Early symptoms of hepatitis X infection can be mistaken for influenza, but some sufferers, especially children, exhibit no symptoms at all. Symptoms typically appear 1 to 2 weeks, (the incubation period ), after the initial infection.

There is currently no specific therapy. Intravenous fluids and treatment of the hepatic encephalopathy may help. Increasing dietary levels of branched chain amino acids and feeding low protein diets can help signs of hepatic encephalopathy, which is often accomplished by feeding small amounts of grain and/or beet pulp, and removing high-protein feedstuffs such as alfalfa hay. Grazing on non-legume grass may be acceptable if it is late summer or fall, although the horse should only be permitted to eat in the evening so as to avoid photosensitization. Due to the risk of gastric impaction, stomach size should be monitored.

Sedation is minimized and used only to control behavior that could lead to injury of the animal and to allow therapeutic procedures, and should preferably involve a sedative other than a benzodiazepine. Stressing the animal should be avoided if at all possible. Plasma transfusions may be needed if spontaneous bleeding occurs, to replace clotting factors. Antibiotics are sometimes prescribed to prevent bacterial translocation from the intestines. Antioxidants such as vitamin E, B-complex vitamins, and acetylcysteine may be given. High blood ammonia is often treated with oral neomycin, often in conjunction with lactulose, metronidazole and probiotics, to decrease production and absorption of ammonia from the gastrointestinal tract.

Many people with hepatitis will prefer bed rest, though it is not necessary to avoid all physical activity while recovering. A high-calorie diet is recommended. Many people develop nausea and cannot tolerate food later in the day, so the bulk of intake may be concentrated in the earlier part of the day. In the acute phase of the disease, intravenous feeding may be needed if patients cannot tolerate food and have poor oral intake subsequent to nausea and vomiting.

People with hepatitis should avoid taking drugs metabolized by the liver. Glucocorticoids are not recommended as a treatment option for acute viral hepatitis and may even cause harm, such as development of chronic hepatitis.

Universal precautions should be observed, but isolation is not strictly necessary; isolation may be needed in cases of fecal incontinence in hepatitis A and E and uncontrolled bleeding in hepatitis B and C.

Hepatitis A causes an acute illness that does not progress to chronic liver disease. Therefore, the role of screening is to assess immune status in people who are at high risk of contracting the virus, as well as in people with known liver disease for whom hepatitis A infection could lead to liver failure. People in these groups who are not already immune can receive the hepatitis A vaccine.

Those at high risk and in need of screening include:

- People with poor sanitary habits such as not washing hands after using the restroom or changing diapers

- People who do not have access to clean water

- People in close contact (either living with or having sexual contact) with someone who has hepatitis A

- Illicit drug users

- People with liver disease

- People traveling to an area with endemic hepatitis A

The presence of anti-hepatitis A IgG in the blood indicates past infection with the virus or prior vaccination.

In the United States in 1991, the mortality rate for hepatitis A was estimated to be 0.015% for the general population, but ranged up to 1.8 -2.1 % for those aged 50 and over which were hospitalized with icteric hepatitis. The risk of death from acute liver failure following HAV infection increases with age and when the person has underlying chronic liver disease.

Young children who are infected with hepatitis A typically have a milder form of the disease, usually lasting 1–3 weeks, whereas adults tend to experience a much more severe form of the disease.

, there are about one hundred medications in development for hepatitis C. These include vaccines to treat hepatitis, immunomodulators, and cyclophilin inhibitors, among others. These potential new treatments have come about due to a better understanding of the hepatitis C virus. There are a number of vaccines under development and some have shown encouraging results.

The combination of sofosbuvir and velpatasvir in one trial (reported in 2015) resulted in cure rates of 99%.

The responses to treatment is measured by "sustained viral response" (SVR), defined as the absence of detectable RNA of the hepatitis C virus in blood serum for at least 24 weeks after discontinuing the treatment, and rapid virological response (RVR) defined as undetectable levels achieved within four weeks of treatment. Successful treatment decreases the future risk of hepatocellular carcinoma by 75%.

Prior to 2012 sustained response occurs in about 40–50% in people with HCV genotype 1 given 48 weeks of treatment. A sustained response is seen in 70–80% of people with HCV genotypes 2 and 3 with 24 weeks of treatment. A sustained response occurs about 65% in those with genotype 4 after 48 weeks of treatment. The evidence for treatment in genotype 6 disease is sparse and what evidence there is supports 48 weeks of treatment at the same doses used for genotype 1 disease.

There is no specific treatment for neonatal hepatitis. Vitamin supplements are usually prescribed and many infants are given phenobarbital, a drug used to control seizures, but which also stimulates the liver to excrete additional bile. Formulas containing more easily digested fats are also given to the infant.

Neonatal hepatitis caused by the hepatitis A virus also usually resolves itself within six months, but cases that are the result of infection with the hepatitis B or hepatitis C viruses most likely will result in chronic liver disease. Infants who develop cirrhosis ultimately will need a liver transplant.

In assisted reproductive technology, sperm washing is not necessary for males with hepatitis B to prevent transmission, unless the female partner has not been effectively vaccinated. In females with hepatitis B, the risk of transmission from mother to child with IVF is no different from the risk in spontaneous conception.

Those at high risk of infection should be tested as there is effective treatment for those who have the disease. Groups that screening is recommended for include those who have not been vaccinated and one of the following: people from areas of the world where hepatitis B occurs in more than 2%, those with HIV, intravenous drug users, men who have sex with men, and those who live with someone with hepatitis B.

No specific treatment for hepatitis A is known. Recovery from symptoms following infection may take several weeks or months. Therapy is aimed at maintaining comfort and adequate nutritional balance, including replacement of fluids lost from vomiting and diarrhoea.

The vaccine for hepatitis B protects against hepatitis D virus because of the latter's dependence on the presence of hepatitis B virus for it to replicate.

Latest evidence suggests that Pegylated interferon alpha is effective in reducing the viral load and the effect of the disease during the time the drug is given, but the benefit generally stops if the drug is discontinued. The efficiency of the pegylated interferon treatment does not usually exceed ~20%.

The drug myrcludex B, which inhibits virus entry into hepatocytes, is in clinical trials .

The following therapeutic drugs were withdrawn from the market primarily because of hepatotoxicity: Troglitazone, bromfenac, trovafloxacin, ebrotidine, nimesulide, nefazodone, ximelagatran and pemoline.

Many herbal and antioxidant remedies have been advocated for chronic liver disease but the evidence is not conclusive. Some support may be found in the orthodox medical use of two of these: N-acetyl cysteine (NAC), is the treatment of choice for acetaminophen overdose; both NAC and milk-thistle (Silybum marianum) or its derivative silibinin are used in liver poisoning from certain mushrooms, notably amanita phalloides, although the use of milk-thistle is controversial. Some common herbs are known or suspected to be harmful to the liver, including black cohosh, ma huang, chaparral, comfrey, germander, greater celandine, kava, mistletoe, pennyroyal, skull cap and valerian.

This condition most commonly occurs after the administration of a horse origin biological agent such as equine-derived antiserum, and usually occurs 4–10 weeks after the event. Diseases that have been vaccinated against using equine-origin antiserum, resulting in subsequent Theiler's disease, include: African horse sickness, Eastern and Western Equine Encephalitis, "Bacillus anthracis", tetanus antitoxin, "Clostridium perfringens", "Clostridium botulinum", "Streptococcus equi" subspecies "equi", Equine influenza, Equine herpesvirus type 1, pregnant mare's serum, and plasma. Although it occurs sporadically, It appears to be spreadable within a premises, and there have been outbreaks occurring on farms involving multiple horses over several months. In the Northern hemisphere it is most common between August to November. It is seen almost exclusively in adult horses, and lactating broodmares given tetanus antitoxin post foaling may be more susceptible.

Acute infection does not usually require treatment and most adults clear the infection spontaneously. Early antiviral treatment may be required in fewer than 1% of people, whose infection takes a very aggressive course (fulminant hepatitis) or who are immunocompromised. On the other hand, treatment of chronic infection may be necessary to reduce the risk of cirrhosis and liver cancer. Chronically infected individuals with persistently elevated serum alanine aminotransferase, a marker of liver damage, and HBV DNA levels are candidates for therapy. Treatment lasts from six months to a year, depending on medication and genotype. Treatment duration when medication is taken by mouth, however, is more variable and usually longer than one year.

Although none of the available drugs can clear the infection, they can stop the virus from replicating, thus minimizing liver damage. As of 2008, there are seven medications licensed for the treatment of infection in the United States. These include antiviral drugs lamivudine (Epivir), adefovir (Hepsera), tenofovir (Viread), telbivudine (Tyzeka) and entecavir (Baraclude), and the two immune system modulators interferon alpha-2a and PEGylated interferon alpha-2a (Pegasys). In 2015 the World Health Organization recommended tenofovir or entecavir as first-line agents. Those with current cirrhosis are in most need of treatment.

The use of interferon, which requires injections daily or thrice weekly, has been supplanted by long-acting PEGylated interferon, which is injected only once weekly. However, some individuals are much more likely to respond than others, and this might be because of the genotype of the infecting virus or the person's heredity. The treatment reduces viral replication in the liver, thereby reducing the viral load (the amount of virus particles as measured in the blood). Response to treatment differs between the genotypes. Interferon treatment may produce an e antigen seroconversion rate of 37% in genotype A but only a 6% seroconversion in type D. Genotype B has similar seroconversion rates to type A while type C seroconverts only in 15% of cases. Sustained e antigen loss after treatment is ~45% in types A and B but only 25–30% in types C and D.

In terms of treatment, ribavirin is not registered for hepatitis E treatment, though off-label experience for treating chronic hepatitis E with this compound exists. The use of low doses of ribavirin over a three-month period has been associated with viral clearance in about two-thirds of chronic cases. Other possible treatments include pegylated interferon or a combination of ribavirin and pegylated interferon. In general, chronic HEV infection is associated with immunosuppressive therapies, but remarkably little is known about how different immunosuppressants affect HEV infection. In individuals with solid-organ transplantation, viral clearance can be achieved by temporal reduction of the level of immunosuppression.

A vaccine based on recombinant viral proteins was developed in the 1990s and tested in a high-risk population (in Nepal) in 2001. The vaccine appeared to be effective and safe, but development was stopped for lack of profitability, since hepatitis E is rare in developed countries. No hepatitis E vaccine is licensed for use in the United States.

Although other HEV vaccine trials have been successful, these vaccines have not yet been produced or made available to susceptible populations. The exception is China; after more than a year of scrutiny and inspection by China's State Food and Drug Administration (SFDA), a hepatitis E vaccine developed by Chinese scientists was available at the end of 2012. The vaccine—called HEV 239 by its developer Xiamen Innovax Biotech—was approved for prevention of hepatitis E in 2012 by the Chinese Ministry of Science and Technology, following a controlled trial on 100,000+ people from Jiangsu Province where none of those vaccinated became infected during a 12-month period, compared to 15 in the group given placebo. The first vaccine batches came out of Innovax' factory in late October 2012, to be sold to Chinese distributors.

Due to the lack of evidence, WHO did not make a recommendation regarding routine use of the HEV 239 vaccine. National authorities may however, decide to use the vaccine based on the local epidemiology.

Treatment may involve the prescription of immunosuppressive glucocorticoids such as prednisone, with or without azathioprine, and remission can be achieved in up to 60–80% of cases, although many will eventually experience a relapse. Budesonide has been shown to be more effective in inducing remission than prednisone, and result in fewer adverse effects. Those with autoimmune hepatitis who do not respond to glucocorticoids and azathioprine may be given other immunosuppressives like mycophenolate, ciclosporin, tacrolimus, methotrexate, etc. Liver transplantation may be required if patients do not respond to drug therapy or when patients present with fulminant liver failure.

The most common cause of hepatitis is viral. Although they are classified under the disease hepatitis, these viruses are not all related.

Hepatitis D virus was first reported in the mid-1977 as a nuclear antigen in patients infected with HBV who had severe liver disease. This nuclear antigen was then thought to be a hepatitis B antigen and was called the delta antigen. Subsequent experiments in chimpanzees showed that the hepatitis delta antigen (HDAg) was a structural part of a pathogen that required HBV infection to replicate. The entire genome was cloned and sequenced in 1986. It was subsequently placed in its own genus: "Deltavirus".

The treatment of chronic liver disease depends on the cause. Specific conditions may be treated with medications including corticosteroids, interferon, antivirals, bile acids or other drugs. Supportive therapy for complications of cirrhosis include diuretics, albumin, vitamin K, blood products, antibiotics and nutritional therapy. Other patients may require surgery or a transplant. Transplant is required when the liver fails and there is no other alternative.

Viral hepatitis is liver inflammation due to a viral infection. It may present in acute (recent infection, relatively rapid onset) or chronic forms.

The most common causes of viral hepatitis are the five unrelated hepatotropic viruses hepatitis A, hepatitis B, hepatitis C, hepatitis D, and hepatitis E. In addition to the nominal hepatitis viruses, other viruses that can also cause liver inflammation include cytomegalovirus, Epstein–Barr virus, and yellow fever. Up to 1997 there has been also 52 cases of viral hepatitis caused by herpes simplex virus.

There is the opportunity to prevent or treat the most common types. Hepatitis A and hepatitis B can be prevented by vaccination. Effective treatments for hepatitis C are available but expensive.

In 2013 about 1.5 million people died from viral hepatitis. Most deaths are due to hepatitis B and hepatitis C. East Asia is the region of the world most affected.

Neonatal hepatitis is a form of hepatitis that affects the fetuses and neonates.

Autoimmune hepatitis is not a benign disease. Despite a good initial response to immunosuppression, recent studies suggest that the life expectancy of patients with autoimmune hepatitis is lower than that of the general population. Additionally, presentation and response to therapy appears to differ according to race. For instance, African Americans appear to present with a more aggressive disease that is associated with worse outcomes.