Bysanti: FDA Approves New Atypical Antipsychotic Pill for Adults with Schizophrenia or Manic/Mixed Episodes in Bipolar I Disorder

Bysanti (milsaperidone) is a new FDA-approved oral medicine for treating certain mental health conditions in adults. It belongs to a group of medicines called atypical antipsychotics and is approved for the treatment of schizophrenia, as well as for first-line therapy for the acute treatment of manic or mixed episodes that come with bipolar I disorder.

Bipolar I disorder affects a significant proportion of the 10 million Americans living with bipolar disorder. It is marked by alternating episodes of mania or hypomania and depression, involving severe mood swings – manic episodes come with very high energy, little need for sleep, and impulsive behavior and are sometimes preceded or followed by depression. Quick symptom control is a key treatment.

Schizophrenia affects about 1% of U.S. adults (around 2.8 million people). It can disrupt thinking, emotions, and behavior, sometimes causing hallucinations, fixed false beliefs (delusions), incoherent speech, and social withdrawal. The condition often interferes with daily life and may require long-term medical care.

Bysanti is a new medicine in the atypical antipsychotics class. While its exact way it works is unknown, it is believed that by blocking dopamine D2, serotonin 5-HT2A, and alpha1-adrenergic receptors in the brain, Bysanti helps restore balance between key chemicals in the brain (neurotransmitters) like dopamine and serotonin that affect mood, thinking, and behavior. Once inside the body, Bysanti quickly converts into another active medicine called iloperidone (Fanapt). Both the active molecules work together to block D2, 5-HT2A, and alpha1-adrenergic receptors, adjusting the neurotransmitter signaling involved in these conditions to help reduce symptoms and improve stability.

This approval matters because it provides another atypical antipsychotic option while building on years of experience with iloperidone. But due to a higher risk of death, Bysanti and other antipsychotic drugs are not approved for use in elderly patients with dementia-related psychosis.

Why Was It Approved?

The FDA’s approval was supported by clinical studies that showed that Bysanti worked in the same way as the previously studied and approved atypical antipsychotic medicine iloperidone. In these studies, Bysanti was shown to be bioequivalent to iloperidone across the full dosing range. The bioequivalence studies also confirmed that Bysanti is absorbed and used by the body similarly to iloperidone, whose safety profile is supported by data from thousands of people in trials and over 100,000 patient-years of real-world use.

In schizophrenia studies, the most common side effects were dizziness, dry mouth, fatigue, a stuffy nose, sleepiness, a fast heartbeat, low blood pressure when standing up (orthostatic hypotension), and weight gain. In bipolar mania studies, common side effects included a rapid heartbeat, dizziness, dry mouth, increased liver enzyme levels on blood tests, a stuffy nose, weight gain, low blood pressure, and sleepiness.

What Do I Need to Know?

Bysanti tablets are taken by mouth twice daily, with or without food. Your health care provider will gradually increase your dose to lower the risk of orthostatic hypotension and fainting (syncope). If you miss your dose for more than three days in a row, you will need to restart the dose‑increase plan. Your health care provider may suggest a genetic test to determine how your body processes CYP2D6-related medicines before deciding on your Bysanti dose.

Orthostatic hypotension is possible, especially when starting, restarting, or increasing the dose, so stand up slowly and take other precautions. Your health care provider will monitor your heart rate and blood pressure if you are prone to low blood pressure and have heart disease or problems affecting the blood vessels in your brain.

Bysanti can also lead to high blood sugar levels or changes in cholesterol levels, so regular monitoring of blood sugar and lipid levels is recommended. Patients with a history of low white blood cell counts will be monitored during the early months of Bysanti treatment.

Be sure to tell your health care provider about any health conditions you have and all medicines, supplements, herbal remedies, or vitamins you take to avoid possible interactions. Let your health care provider know if you have a history of liver problems, thyroid problems, seizures, heart-related issues (such as a recent heart attack, unstable angina, heart rhythm defects, heart muscle damage from poor blood flow, or slow/irregular heartbeats), or uncontrolled high blood pressure, as Bysanti can affect heart rhythm by lengthening the QT interval, which may lead to serious heart rhythm problems and even sudden death.

Bysanti should not be taken with other medicines that also prolong the QT interval, because this may result in an abnormal heart rhythm. The risk may increase if you take Bysanti with medicines that affect liver enzymes (CYP2D6 or CYP3A4), which influence how your body processes medications. Avoid combining Bysanti with medicines that lower blood pressure. For patients who are at risk of low potassium or magnesium, your health care provider may check these electrolyte levels before and during treatment.

Avoid strenuous exercise, exposure to extreme heat conditions, dehydration, and overheating, and stay well-hydrated. Be careful while driving or operating machinery until you know how Bysanti affects you. Bysanti may also cause intraoperative floppy iris syndrome (IFIS), so it is important to let your eye surgeon know if you are having cataract or glaucoma surgery or other eye procedures, even if you have stopped taking Bysanti.

Bysanti should not be taken by anyone who has had an allergic reaction to milsaperidone or any other tablet ingredient, and it is not recommended for people with severe liver problems.

Bysanti may also cause a prolonged painful erection (priapism) that may require surgery. As seen with other medicines that block dopamine D2 receptors, Bysanti may increase prolactin levels, which may cause unexpected breast milk production, missed periods, enlargement of breasts in men, or impotence.

Use in late pregnancy may cause movement or withdrawal symptoms in newborns, and breastfeeding is not advised while you take the medication. After your last Bysanti dose, wait for six days if you process the medicine normally or eight days if you process it slowly. This depends on your liver enzyme (CYP2D6) activity, and your health care provider can guide you.

Patients and caregivers should watch for unusual involuntary movements, which could indicate tardive dyskinesia, and contact your health care provider if they occur.

Though rare, a serious condition called neuroleptic malignant syndrome can occur, so contact your health care provider at once if you have a high fever, severe muscle stiffness, confusion, unusual behavior, changes in blood pressure, an irregular heartbeat, heavy sweating, or abnormal heart rhythms.

Bysanti is expected to be available in the U.S. in the third quarter of 2026.