Rexulti (brexpiprazole) is a popular add-on for psychiatric treatment in the United States. As such, it pays to know a little bit more about this medication, including how long Rexulti stays in your system.
The FDA states the following information regarding Rexulti half-life:
Elimination half-life: 91 hours (brexpiprazole), 86 hours (major metabolite)
Time to steady-state: within 10 to 12 days of dosing
Peak plasma concentrations: within 4 hours after administration
Rexulti has an oral bioavailability of 95%. The body primarily excretes brexpiprazole through feces and urine as metabolites. Research shows that OPC-3952 is the primary metabolite present in patient urine.
What is the half-life of Rexulti?
The half-life of Rexulti is 91 hours.
How long does Rexulti stay in your system?
The half-life of Rexulti is 91 hours. Since it takes about 4 to 5 half-lives for the body to completely clear most drugs, that means it can take up to 455 hours (nearly 19 days) for the body to clear brexpiprazole.
Sometimes, doctors may test for this medication to determine if a patient really is taking Rexulti. Tests for this medication include the following:
- Urine: Urine tests for this medication may look for the metabolite OPC-3952, which is the primary metabolite present in urine after taking this medication
- Blood: Blood tests are a popular way to test for patient compliance; blood tests are also commonly used with this medication to monitor white blood cell count and blood sugar levels, as brexpiprazole may affect them
- Plasma/Serum: Doctors may check plasma/serum (more commonly known as blood tests) for patient compliance, as this drug is “highly protein bound in plasma (greater than 99%).” It can take about 4 hours after a single dose for this medication to reach peak plasma concentration levels. Typically, steady-state plasma levels for schizophrenic adults with regular dosing is as follows:
- 1 mg – 21 to 39 ng/mL
- 2 mg – 56 to 81 ng/mL
- 4 mg – 112 to 199 ng/mL
- 8 mg – 171 to 276 ng/mL
- 12 mg – 205 to 382 ng/mL
How long does brexpiprazole take to work?
How long Rexulti takes to work may vary from patient to patient, as not everyone responds to this medication the same way. Keep your doctor updated on how you are feeling, including any side effects, so that they can better understand what effect the treatment is having on you and adjust it if necessary.
That being said, it can take a week or two for some symptoms to start improving. Although, it may take up to 3 months before you start to feel the full effects of brexpiprazole.
How long does Rexulti withdrawal last?
Rexulti’s withdrawal symptoms appear within the first few days of stopping or substantially reducing drug dosage. They tend to peak within a week from stopping the medication and start to ease after that.
Can you just stop taking Rexulti?
No, it is best to follow your doctor’s advice on how to stop gradually.
Does Rexulti increase dopamine?
Rexulti is a dopamine D2 receptor partial agonist, also described as a serotonin-dopamine activity modulator. These terms mean that it works on specific serotonin and dopamine receptors in the brain, helping to increase these specific receptors’ activity.