Brexpiprazole, sold under the brand name Rexulti among others, is an atypical antipsychotic medication used for the treatment of major depressive disorder, schizophrenia, and agitation associated with dementia due to Alzheimer's disease.

[12] The most common side effects among people with agitation associated with dementia due to Alzheimer's disease include headache, dizziness, urinary tract infection, nasopharyngitis, and sleep disturbances (both somnolence and insomnia).

[18] Brexpiprazole is the first treatment approved by the US Food and Drug Administration (FDA) for agitation associated with dementia due to Alzheimer's disease.

For aripiprazole, this means more dopamine receptor activation at lower doses, with blockade being reached at higher doses, while brexpiprazole has the inverse effect because a partial agonist is considered to terminate its motoric side effects due to their agonistic behaviour which gets suppressed earlier with lower dosages when thei have a less intrinsic value, this is also the reason (nevertheless with the seemingly against-decided competition in the antipsychotika of choice, and this also with the fact, that brexpiprazole fell into the age of development having much more informationpriviliges of considering and adjust of its maximum recommended dose, right under before it went offlabel) why through its significant lower value than all other neuroleptics from the 3rd generation (e.g. cariprazine(D3,70% for example) it could be considered as working with some similar efficiacy than a full antagonist (like perphenazine) at the D2 receptor so a receptoroccupation of only 68+% at the maximum recommended dose is seen enough (compared with the needable occupation of 90% at the D2 receptor when administered aripiprazole or cariprazin)[29][30][31].

This may further underlie a lower potential than aripiprazole to cause treatment-emergent, movement-related disorders such as akathisia due to the downstream dopamine release that is triggered by 5-HT1A receptor agonism.

[13] The phase II multicenter, double-blind, placebo-controlled study randomized 429 adult MDD patients who exhibited an inadequate response to one to three approved antidepressant treatments (ADTs) in the current episode.

[41] Its goal is "to compare the effect of brexpiprazole to the effect of placebo (an inactive substance) as add on treatment to an assigned FDA approved antidepressant treatment (ADT) in patients with major depressive disorder who demonstrate an incomplete response to a prospective trial of the same assigned FDA approved ADT".

The effectiveness of brexpiprazole for the treatment of agitation associated with dementia due to Alzheimer's disease was determined through two 12-week, randomized, double-blind, placebo-controlled, fixed-dose studies.