Rexulti vs Abilify for Sedation
Abilify (aripiprazole) is less sedating than most antipsychotics and has a lower sedation profile compared to other options, while Rexulti (brexpiprazole) has even less propensity for sedation due to its pharmacological profile. 1, 2
Pharmacological Differences
- Brexpiprazole (Rexulti) displays less intrinsic activity at D2 receptors compared to aripiprazole (Abilify), which contributes to its lower propensity for activating adverse events 2
- Both medications are partial agonists at dopamine D2 and serotonin 5-HT1A receptors and antagonists at serotonin 5-HT2A receptors, but with different receptor binding profiles 3, 4
- Brexpiprazole's receptor binding profile shows actions at 5HT1A, 5HT2A and noradrenaline α1B receptors that are at least as potent as its action at D2 receptors, resulting in fewer activating side effects 2
Sedation Profiles
- Aripiprazole has a lower sedation profile compared to many other antipsychotics (such as olanzapine and quetiapine), making it a preferable option when sedation is a concern 1
- Brexpiprazole is characterized by a relatively low incidence of both activating and sedating adverse effects compared to other antipsychotics 2
- Clinical evidence suggests brexpiprazole has an even lower propensity for sedation than aripiprazole due to its modified receptor binding profile 2, 3
Clinical Considerations
- Aripiprazole's lack of a sedative effect does not impact its efficacy in controlling symptoms such as mania and agitation 5
- Brexpiprazole was generally well tolerated in clinical trials with a favorable adverse event profile, including low rates of sedation 2
- When treating patients where minimal sedation is desired, aripiprazole may be preferred over more sedating antipsychotics, but brexpiprazole may offer even less sedation 1, 2
Side Effect Comparison
- Aripiprazole is associated with more akathisia (an activating side effect) compared to some other antipsychotics 6
- Common side effects of aripiprazole include headache, agitation, anxiety, insomnia, dizziness, and drowsiness 1
- Brexpiprazole shows small changes in metabolic parameters that are not clinically significant and moderate weight gain 2
Practical Recommendations
- For patients where sedation is a significant concern, brexpiprazole would be the preferred choice over aripiprazole based on its pharmacological profile 2, 3
- In situations where cost is a factor, aripiprazole may be more accessible and still offers a relatively low sedation profile compared to many other antipsychotics 1, 5
- Lower doses of either medication should be considered for elderly patients, those with hepatic impairment, or poor metabolizers of cytochrome P450 2D6 1