The onset of Wernicke's encephalopathy is considered a medical emergency, and thus thiamine administration should be initiated immediately when the disease is suspected. Prompt administration of thiamine to patients with Wernicke's encephalopathy can prevent the disorder from developing into Wernicke–Korsakoff syndrome, or reduce its severity. Treatment can also reduce the progression of the deficits caused by WKS, but will not completely reverse existing deficits. WKS will continue to be present, at least partially, in 80% of patients. Patients suffering from WE should be given a minimum dose of 500 mg of thiamine hydrochloride, delivered by infusion over a 30-minute period for two to three days. If no response is seen then treatment should be discontinued but for those patients that do respond, treatment should be continued with a 250 mg dose delivered intravenously or intramuscularly for three to five days unless the patient stops improving. Such prompt administration of thiamine may be a life-saving measure. Banana bags, a bag of intravenous fluids containing vitamins and minerals, is one means of treatment.

It was once assumed that anyone suffering from Korsakoff's syndrome would eventually need full-time care. This is still often the case, but rehabilitation can help regain some, albeit often limited, level of independence. Treatment involves the replacement or supplementation of thiamine by intravenous (IV) or intramuscular (IM) injection, together with proper nutrition and hydration. However, the amnesia and brain damage caused by the disease does not always respond to thiamine replacement therapy. In some cases, drug therapy is recommended. Treatment of the patient typically requires taking thiamine orally for 3 to 12 months, though only about 20 percent of cases are reversible. If treatment is successful, improvement will become apparent within two years, although recovery is slow and often incomplete.

As an immediate form of treatment, a pairing of IV or IM thiamine with a high concentration of B-complex vitamins can be administered three times daily for period of 2–3 days. In most cases, an effective response from patients will be observed. A dose of 1 gram of thiamine can also be administered to achieve a clinical response. In patients who are seriously malnourished, the sudden availability of glucose without proper bodily levels of thiamine to metabolize is thought to cause damage to cells. Thus, the administration of thiamine along with an intravenous form of glucose is often good practice.

Treatment for the memory aspect of Korsakoff's syndrome can also include domain-specific learning, which when used for rehabilitation is called the method of vanishing cues. Such treatments aim to use patients' intact memory processes as the basis for rehabilitation. Patients who used the method of vanishing cues in therapy were found to learn and retain information more easily.

People diagnosed with Korsakoff's are reported to have a normal life expectancy, presuming that they abstain from alcohol and follow a balanced diet. Empirical research has suggested that good health practices have beneficial effects in Korsakoff's syndrome.

As described, Korsakoff 's syndrome usually follows or accompanies Wernicke's encephalopathy. If treated quickly, it may be possible to prevent the development of Korsakoff's syndrome with thiamine treatments. This treatment is not guaranteed to be effective and the thiamine needs to be administered adequately in both dose and duration. A study on Wernicke-Korsakoff's syndrome showed that with consistent thiamine treatment there were noticeable improvements in mental status after only 2–3 weeks of therapy. Thus, there is hope that with treatment Wernicke's encephalopathy will not necessarily progress to WKS.

In order to reduce the risk of developing WKS it is important to limit the intake of alcohol or drink in order to ensure that proper nutrition needs are met. A healthy diet is imperative for proper nutrition which, in combination with thiamine supplements, may reduce the chance of developing WKS. This prevention method may specifically help heavy drinkers who refuse to or are unable to quit.

Treatment for confabulation is somewhat dependent on the cause or source, if identifiable. For example, treatment of Wernicke–Korsakoff syndrome involves large doses of vitamin B in order to reverse the thiamine deficiency. If there is no known physiological cause, more general cognitive techniques may be used to treat confabulation. A case study published in 2000 showed that Self-Monitoring Training (SMT) reduced delusional confabulations. Furthermore, improvements were maintained at a three-month follow-up and were found to generalize to everyday settings. Although this treatment seems promising, more rigorous research is necessary to determine the efficacy of SMT in the general confabulation population.

Aside from discontinuation of glucocorticoid medication, potential treatments discussed in the research literature include:

- anti-glucocorticoids

- psychoactive drugs that up-regulate the GRII glucocorticoid receptor:

- tricyclic antidepressants: Desipramine, Imipramine, and Amitriptyline (SSRIs do not )

- serotonin antagonists: Ketanserin

- mood stabilizers: Lithium

- corticotropin-releasing hormone (CRH) antagonists

- glutamate antagonists

- dehydroepiandrosterone (DHEA)

- small molecule brain-derived neurotrophic factor (BDNF) analogs

- stress reduction therapies and exercise.

Most symptoms will improve quickly if deficiencies are treated early. Memory disorder may be permanent.

In patients suspected of WE, thiamine treatment should be started immediately. Blood should be immediately taken to test for thiamine, other vitamins and minerals levels. Following this an immediate intravenous or intramuscular dose of thiamine should be administered two or three times daily. Thiamine administration is usually continued until clinical improvement ceases.

Considering the diversity of possible causes and several surprising symptomatologic presentations, and because there is low assumed risk of toxicity of thiamine, because the therapeutic response is often dramatic from the first day, some qualified authors indicate parenteral thiamine if WE is suspected, both as a resource for diagnosis and treatment. The diagnosis is highly supported by the response to parenteral thiamine, but is not sufficient to be excluded by the lack of it. Parenteral thiamine administration is associated with a very small risk of anaphylaxis.

Alcohol abusers may have poor dietary intakes of several vitamins, and impaired thiamine absorption, metabolism, and storage; they may thus require higher doses.

If glucose is given, such as in hypoglycaemic alcoholics, thiamine must be given concurrently. If this is not done, the glucose will rapidly consume the remaining thiamine reserves, exacerbating this condition.

The observation of edema in MR, and also the finding of inflation and macrophages in necropsied tissues, has led to successful administration of antiinflammatories.

Other nutritional abnormalities should also be looked for, as they may be exacerbating the disease. In particular, magnesium, a cofactor of transketolase which may induce or aggravate the disease.

Other supplements may also be needed, including: cobalamin, ascorbic acid, folic acid, nicotinamide, zinc, phosphorus (dicalcium phosphate) and in some cases taurine, especially suitable when there cardiocirculatory impairment.

Patient-guided nutrition is suggested. In patients with Wernicke-Korsakoff syndrome, even higher doses of parenteral thiamine are recommended. Concurrent toxic effects of alcohol should also be considered.

The most effective method of preventing Korsakoff's syndrome is to avoid B vitamin/thiamine deficiency. In Western nations, the most common causes of such a deficiency are alcoholism and eating disorders. Because these are behavioral-induced causes, Korsakoff's syndrome is essentially considered a preventable disease. Thus, fortifying foods with thiamine, or requiring companies that sell alcoholic beverages to supplement them with B vitamins in general or thiamine in particular, could avert many cases of Korsakoff's Syndrome.

If the symptoms of alcohol dementia are caught early enough, the effects may be reversed. The person must stop drinking and start on a healthy diet, replacing the lost vitamins, including, but not limited to, thiamine. Recovery is more easily achievable for women than men, but in all cases it is necessary that they have the support of family and friends and abstain from alcohol.

There are hospital protocols for prevention, supplementing with thiamine in the presence of: history of alcohol misuse or related seizures, requirement for IV glucose, signs of malnutrition, poor diet, recent diarrhea or vomiting, peripheral neuropathy, intercurrent illness, delirium tremens or treatment for DTs, and others. Some experts advise parenteral thiamine should be given to all at-risk patients in the emergency room.

In the clinical diagnosis should be remembered that early symptoms are nonspecific, and it has been stated that WE may present nonspecific findings. There is consensus to provide water-soluble vitamins and minerals after gastric operations.

In some countries certain foods have been supplemented with thiamine, and have reduced WE cases. Improvement is difficult to quantify because they applied several different actions. Avoiding alcohol and having adequate nutrition reduces one of the main risk factors in developing Wernicke-Korsakoff syndrome.

Initial treatment is aimed at providing symptomatic relief. Benzodiazepines are the first line of treatment, and high doses are often required. A test dose of intramuscular lorazepam will often result in marked improvement within half an hour. In France, zolpidem has also been used in diagnosis, and response may occur within the same time period. Ultimately the underlying cause needs to be treated.

Electroconvulsive therapy (ECT) is an effective treatment for catatonia. Antipsychotics should be used with care as they can worsen catatonia and are the cause of neuroleptic malignant syndrome, a dangerous condition that can mimic catatonia and requires immediate discontinuation of the antipsychotic.

Excessive glutamate activity is believed to be involved in catatonia; when first-line treatment options fail, NMDA antagonists such as amantadine or memantine are used. Amantadine may have an increased incidence of tolerance with prolonged use and can cause psychosis, due to its additional effects on the dopamine system. Memantine has a more targeted pharmacological profile for the glutamate system, reduced incidence of psychosis and may therefore be preferred for individuals who cannot tolerate amantadine. Topiramate is another treatment option for resistant catatonia; it produces its therapeutic effects by producing glutamate antagonism via modulation of AMPA receptors.

Glucocorticoid medications have been known to be associated with significant side effects involving behavior and mood, regardless of previous psychiatric or cognitive condition, since the early 1950s. But cognitive side effects of steroid medications involving memory and attention are not as widely publicized and may be misdiagnosed as separate conditions, such as attention deficit disorder (ADHD or ADD) in children or early Alzheimer's disease in elderly patients.

Current methods in treating early-onset schizophrenia follow a similar approach to the treatment of adult schizophrenia. Although modes of treatment in this population is largely understudied, the use of antipsychotic medication is commonly the first line of treatment in addressing symptoms. Recent literature has failed to determine if typical or atypical antipsychotics are most effective in reducing symptoms and improving outcomes. When weighing treatment options, it is necessary to consider the adverse effects of various medications used to treat schizophrenia and the potential implications of these effects on development. A 2013 systematic review compared the efficacy of atypical antipsychotics versus typical antipsychotics for adolescents:

Madaan et al. wrote that studies report efficacy of typical neuroleptics such as thioridazine, thiothixene, loxapine and haloperidol, high incidence of side effects such as extrapyramidal symptoms, akathisia, dystonias, sedation, elevated prolactin, tardive dyskinesia.

Treatment consists of supportive care during the acute intoxication phase: maintaining hydration, body temperature, blood pressure, and heart rate at acceptable levels until the drug is sufficiently metabolized to allow vital signs to return to baseline. Typical and atypical antipsychotics have been shown to be helpful in the early stages of treatment. This is followed by abstinence from psychostimulants supported with counseling or medication designed to assist the individual preventing a relapse and the resumption of a psychotic state.

Confabulations can also be detected using a free recall task, such as a self-narrative task. Participants are asked to recall stories (semantic or autobiographical) that are highly familiar to them. The stories recalled are encoded for errors that could be classified as distortions in memory. Distortions could include falsifying true story elements or including details from a completely different story. Errors such as these would be indicative of confabulations.

As with other neuroleptic-induced tardive syndromes, there is no definite treatment for tardive dysphrenia. The continuing to take the drug or changing the dosage of the atypical antipsychotic drug in use, or augmenting it with a typical antipsychotic, can alleviate symptoms temporarily. However, these solutions carry the risk of worsening or perpetuating the iatrogenesis in the long term.

Some patients could gradually benefit from changing to a dopamine D2 receptor partial agonist agent like clozapine. These drugs do not induce up-regulation, instead acting as a prophylactic.

Pharmaceutical management, as with Parkinson's disease, involves striking a balance between treating the motor, emotive, and cognitive symptoms. Motor symptoms appear to respond somewhat to the medications used to treat Parkinson's disease (e.g. levodopa), while cognitive issues may improve with medications for Alzheimer's disease such as donepezil. Medications used in the treatment of ADHD (e.g. methylphenidate) might improve cognition or daytime sleepiness; however, medications for both Parkinson's disease and ADHD increase levels of the chemical dopamine in the brain, so increase the risk of hallucinations with those classes of pharmaceuticals.

Treatment of the movement and cognitive portions of the disease may worsen hallucinations and psychosis, while treatment of hallucinations and psychosis with antipsychotics may worsen parkinsonian or ADHD symptoms in DLB, such as tremor or rigidity and lack of concentration or impulse control. Physicians may find the use of cholinesterase inhibitors represents the treatment of choice for cognitive problems and donepezil (Aricept), rivastigmine (Exelon), and galantamine (Reminyl) may be recommended as a means to help with these problems and to slow or prevent the decline of cognitive function. DLB may be more responsive to donepezil than Alzheimer's disease. Memantine also may be useful. Levocarb may help with movement problems, but in some cases, as with dopamine agonists, may tend to aggravate psychosis in people with DLB. Clonazepam may help with rapid eye movement behavior disorder; table salt or antihypotensive medications may help with fainting and other problems associated with orthostatic hypotension. Botulinum toxin injections in the parotid glands may help with sialorrhea. Other medications, especially stimulants such as the ADHD drug methylphenidate (Ritalin) and modafinil, may improve daytime alertness, but as with the antiparkinsonian drug Levocarb, antihyperkinetics such as Ritalin increase the risk of psychosis. Experts advise extreme caution in the use of antipsychotic medication in people with DLB because of their sensitivity to these agents. When these medications must be used, atypical antipsychotics are preferred to typical antipsychotics; a very low dose should be tried initially and increased slowly, and patients should be carefully monitored for adverse reactions to the medications.

Due to hypersensitivity to neuroleptics, preventing DLB patients from taking these medications is important. People with DLB are at risk for neuroleptic malignant syndrome, a life-threatening illness, because of their sensitivity to these medications, especially the older typical antipsychotics, such as haloperidol. Other medications, including medications for urinary incontinence and the antihistamine medication diphenhydramine (Benadryl), also may worsen confusion.

Treatment varies according to the type and severity of the encephalopathy. Anticonvulsants may be prescribed to reduce or halt any seizures. Changes to diet and nutritional supplements may help some patients. In severe cases, dialysis or organ replacement surgery may be needed.

Sympathomimetic drugs can increase motivation, cognition, motor performance and alertness in patients with encephalopathy caused by brain injury, chronic infections, strokes, brain tumors.

Hospitalization may be necessary during the acute phase of symptoms, and psychiatric care if the patient is a danger to self or others. A neurological consult is advised to rule out any organic cause.

The treatment of psychosis depends on the specific diagnosis (such as schizophrenia, bipolar disorder or substance intoxication). The first-line psychiatric treatment for many psychotic disorders is antipsychotic medication, which can reduce the positive symptoms of psychosis in about 7 to 14 days.

The choice of which antipsychotic to use is based on benefits, risks, and costs. It is debatable whether, as a class, typical or atypical antipsychotics are better. Tentative evidence supports that amisulpride, olanzapine, risperidone and clozapine may be more effective for positive symptoms but result in more side effects. Typical antipsychotics have equal drop-out and symptom relapse rates to atypicals when used at low to moderate dosages. There is a good response in 40–50%, a partial response in 30–40%, and treatment resistance (failure of symptoms to respond satisfactorily after six weeks to two or three different antipsychotics) in 20% of people. Clozapine is an effective treatment for those who respond poorly to other drugs ("treatment-resistant" or "refractory" schizophrenia), but it has the potentially serious side effect of agranulocytosis (lowered white blood cell count) in less than 4% of people.

Most people on antipsychotics get side effects. People on typical antipsychotics tend to have a higher rate of extrapyramidal side effects while some atypicals are associated with considerable weight gain, diabetes and risk of metabolic syndrome; this is most pronounced with olanzapine, while risperidone and quetiapine are also associated with weight gain. Risperidone has a similar rate of extrapyramidal symptoms to haloperidol.

The first-line psychiatric treatment for schizophrenia is antipsychotic medication, which can reduce the positive symptoms of psychosis in about 7 to 14 days. Antipsychotics, however, fail to significantly improve the negative symptoms and cognitive dysfunction. In those on antipsychotics, continued use decreases the risk of relapse. There is little evidence regarding effects from their use beyond two or three years. However use of anti-psychotics can lead to dopamine hypersensitivity increasing the risk of symptoms if antipsychotics are stopped.

The choice of which antipsychotic to use is based on benefits, risks, and costs. It is debatable whether, as a class, typical or atypical antipsychotics are better. Amisulpride, olanzapine, risperidone, and clozapine may be more effective but are associated with greater side effects. Typical antipsychotics have equal drop-out and symptom relapse rates to atypicals when used at low to moderate dosages. There is a good response in 40–50%, a partial response in 30–40%, and treatment resistance (failure of symptoms to respond satisfactorily after six weeks to two or three different antipsychotics) in 20% of people. Clozapine is an effective treatment for those who respond poorly to other drugs ("treatment-resistant" or "refractory" schizophrenia), but it has the potentially serious side effect of agranulocytosis (lowered white blood cell count) in less than 4% of people.

Most people on antipsychotics have side effects. People on typical antipsychotics tend to have a higher rate of extrapyramidal side effects, while some atypicals are associated with considerable weight gain, diabetes and risk of metabolic syndrome; this is most pronounced with olanzapine, while risperidone and quetiapine are also associated with weight gain. Risperidone has a similar rate of extrapyramidal symptoms to haloperidol. It remains unclear whether the newer antipsychotics reduce the chances of developing neuroleptic malignant syndrome or tardive dyskinesia, a rare but serious neurological disorder.

For people who are unwilling or unable to take medication regularly, long-acting depot preparations of antipsychotics may be used to achieve control. They reduce the risk of relapse to a greater degree than oral medications. When used in combination with psychosocial interventions, they may improve long-term adherence to treatment. The American Psychiatric Association suggests considering stopping antipsychotics in some people if there are no symptoms for more than a year.

The primary treatment of schizophrenia is antipsychotic medications, often in combination with psychological and social supports. Hospitalization may occur for severe episodes either voluntarily or (if mental health legislation allows it) involuntarily. Long-term hospitalization is uncommon since deinstitutionalization beginning in the 1950s, although it still occurs. Community support services including drop-in centers, visits by members of a community mental health team, supported employment and support groups are common. Some evidence indicates that regular exercise has a positive effect on the physical and mental health of those with schizophrenia.

No cure for dementia with Lewy bodies is known. Treatment may offer symptomatic benefit, but remains palliative in nature. Current treatment modalities are divided into pharmaceutical and caregiving.

The evidence for the effectiveness of early interventions to prevent psychosis appeared inconclusive. Whilst early intervention in those with a psychotic episode might improve short term outcomes, little benefit was seen from these measures after five years. However, there is evidence that cognitive behavioral therapy (CBT) may reduce the risk of becoming psychotic in those at high risk, and in 2014 the UK National Institute for Health and Care Excellence (NICE) recommended preventive CBT for people at risk of psychosis.

Treatment of secondary forms of delusional parasitosis are addressed by treating the primary associated psychological or physical condition. The primary form is treated much as other delusional disorders and schizophrenia. In the past, pimozide was the drug of choice when selecting from the typical antipsychotics. Currently, atypical antipsychotics such as olanzapine or risperidone are used as first line treatment.

However, it is also characteristic that sufferers will reject the diagnosis of delusional parasitosis by medical professionals, and very few are willing to be treated, despite demonstrable efficacy of treatment.

Before beginning treatment for mania, careful differential diagnosis must be performed to rule out secondary causes.

The acute treatment of a manic episode of bipolar disorder involves the utilization of either a mood stabilizer (valproate, lithium, or carbamazepine) or an atypical antipsychotic (olanzapine, quetiapine, risperidone, or aripiprazole). Although hypomanic episodes may respond to a mood stabilizer alone, full-blown episodes are treated with an atypical antipsychotic (often in conjunction with a mood stabilizer, as these tend to produce the most rapid improvement).

When the manic behaviours have gone, long-term treatment then focuses on prophylactic treatment to try to stabilize the patient's mood, typically through a combination of pharmacotherapy and psychotherapy. The likelihood of having a relapse is very high for those who have experienced two or more episodes of mania or depression. While medication for bipolar disorder is important to manage symptoms of mania and depression, studies show relying on medications alone is not the most effective method of treatment. Medication is most effective when used in combination with other bipolar disorder treatments, including psychotherapy, self-help coping strategies, and healthy lifestyle choices.

Lithium is the classic mood stabilizer to prevent further manic and depressive episodes. A systematic review found that long term lithium treatment substantially reduces the risk of bipolar manic relapse, by 42%. Anticonvulsants such as valproate, oxcarbazepine and carbamazepine are also used for prophylaxis. More recent drug solutions include lamotrigine, which is another anticonvulsant. Clonazepam (Klonopin) is also used. Sometimes atypical antipsychotics are used in combination with the previous mentioned medications as well, including olanzapine (Zyprexa) which helps treat hallucinations or delusions, Asenapine (Saphris, Sycrest), aripiprazole (Abilify), risperidone, ziprasidone, and clozapine which is often used for people who do not respond to lithium or anticonvulsants.

Verapamil, a calcium-channel blocker, is useful in the treatment of hypomania and in those cases where lithium and mood stabilizers are contraindicated or ineffective. Verapamil is effective for both short-term and long-term treatment.

Antidepressant monotherapy is not recommended for the treatment of depression in patients with bipolar disorders I or II, and no benefit has been demonstrated by combining antidepressants with mood stabilizers in these patients.