Medication guide

Brexpiprazole (Rexulti)

What is brexpiprazole?

Brexpiprazole is known as Rexulti in the United States and Japan alike (レキサルティ on Japanese packaging). It's a dopamine-and-serotonin-balancing medication in the family called antipsychotics, a name that describes the drug group, not what taking it says about you. It's a newer relative of aripiprazole (Abilify), designed along the same lines.

How is it different from other antipsychotics?

A balancer, not a blocker: like aripiprazole, it steadies dopamine signalling in both directions
Restlessness (akathisia) is less common at the low dose used with an antidepressant: it becomes more common if the dose is raised, so it is watched for
One of the gentler options in its family for weight and blood sugar: both are still monitored
One medicine, more than one use: it treats schizophrenia, and is also used at a low dose alongside an antidepressant

What is it used for in Japan?

Schizophrenia
Depression, as an add-on when an antidepressant alone hasn't been enough
Overactivity or aggressive behaviour driven by agitation in Alzheimer's-type dementia

For dementia, it is used only when non-drug approaches haven't helped enough, and the decision is weighed carefully, because antipsychotics have been linked to a higher risk of death in older people with dementia.

How does it help?

By steadying dopamine and serotonin activity, it calms symptoms and helps lift a stalled response to an antidepressant. Some effect can appear within the first weeks; give it time and keep taking it as prescribed.

What should I tell my doctor before starting?

A few situations rule it out entirely; your doctor will choose something else if any of these apply:

A past allergic reaction to brexpiprazole
Being in a coma, or under the strong influence of sedatives such as barbiturates, or of anesthetics
Treatment with adrenaline (epinephrine), except emergency allergy injections and some dental anesthesia

And tell your doctor first if any of these apply; these usually just need adjustments or a closer eye:

Diabetes, high blood sugar, or a family history of diabetes
Heart disease, a past stroke, or low blood pressure
Certain antifungals or antibiotics (like itraconazole or clarithromycin), or the antidepressant paroxetine; these raise brexpiprazole's level, so the combination is avoided where possible, or the dose is adjusted
The epilepsy medicine carbamazepine, which lowers brexpiprazole's level
Blood pressure medicines
Severe kidney problems, or moderate to severe liver problems (a lower dose, or a longer gap between doses, may be used)
A history of seizures
Thoughts of suicide, now or in the past
Other sedating medicines, or regular alcohol use; they amplify drowsiness
Pregnant, planning to be, or breastfeeding (see the section below)

Your doctor may check your weight and blood sugar now and then. If you notice unusual thirst, drinking a lot, or passing urine much more than usual, stop taking it and see a doctor straight away.

How do I take it, and what if I miss a dose?

Brexpiprazole is taken once a day, with or without food.

If you miss a dose: take it when you remember, unless the next dose is close; in that case just skip. Never take a double dose to catch up
Restlessness: if it appears (see below), report it early rather than enduring it
Light-headedness on standing: it can happen when starting or raising the dose, so get up slowly at first

What side effects should I expect?

Many are mild and ease as your body adjusts, and many can be eased with a counter-medicine if needed. Not everyone gets them.

Restlessness or an urge to keep moving (akathisia): more likely if the dose is raised, and the one to tell us about early; lowering the dose or adding a medicine that counters it usually settles it
Weight gain, in some people
Trouble sleeping, or drowsiness
Headache
A rise in prolactin (a hormone), which can affect periods or cause breast changes; tell your doctor if you notice this

If anything is bothering you, tell your doctor; there's often a way to adjust. And if you ever feel worse instead of better, tell us straight away; it's easily managed, and that's what we're here for.

Finally, two things that are rare enough that most people never experience them, but knowing them makes them easy to handle:

A combination of high fever, muscle stiffness, and confusion (on the order of 1 in 1,000 people or fewer): if this happens, get medical care promptly; recognised early, it's manageable
New strong urges that are hard to resist (gambling, spending, eating, or sex): just mention it if you notice them; the usual step is to lower the dose or stop the medicine

Will I become dependent? How do I stop safely?

No; brexpiprazole isn't addictive and doesn't cause cravings. Stopping is mainly about timing: coming off too early can let symptoms return, so the decision and the pace are planned with your doctor. Don't stop it on your own, even when you feel well; feeling well is usually the medicine doing its job.

Can I drive while taking it?

The Japanese label advises against driving while taking it. Brexpiprazole can cause drowsiness, and the label here instructs that patients on it shouldn't drive or operate dangerous machinery. Discuss your own situation with your doctor, especially when starting or raising the dose.

What about pregnancy and breastfeeding?

Treatment can continue in pregnancy when the benefit is judged to outweigh the risk; the decision is individual. Untreated illness carries real risks in pregnancy too, so this is a planning conversation, not an automatic stop; never stop on your own on learning you're pregnant. If it is used late in pregnancy, the newborn is watched for signs such as poor feeding, sleepiness or stiffness. Breastfeeding is decided case by case. Our guides to medication in pregnancy and medication while breastfeeding cover the details.