Zyprexa vs Rexulti

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For patients dealing with schizophrenia, bipolar disorder or major depressive disorder (MDD), certain medications can help balance the levels of neurotransmitters in the brain that are linked to mood and behavior. Zyprexa and Rexulti are two such drugs frequently prescribed for these conditions. Both work by influencing different neurotransmitter systems within the brain, but each has proven effective at managing symptoms associated with these disorders. Zyprexa is an atypical antipsychotic affecting both serotonin and dopamine receptors, used primarily for treating psychotic conditions like schizophrenia and bipolar disorder. On the other hand, Rexulti also impacts primarily on serotonin and dopamine receptors; however, it has a unique mechanism of action as a partial agonist at 5-HT1A receptors along with its antagonist activity at 5-HT2A and D2 receptors which makes it useful in managing MDD when added to antidepressant therapy.

What is Zyprexa?

Olanzapine (the generic name for Zyprexa) was one of the second-generation antipsychotic drugs, a significant advancement from first-generation antipsychotics. It was first approved by the FDA in 1996. Zyprexa influences multiple neurotransmitters in the brain, including serotonin and dopamine, by blocking their receptors to manage symptoms related to conditions like schizophrenia and bipolar disorder. The drug does not cure these disorders but helps control symptoms such as hallucinations or mood swings.

Brexpiprazole (Rexulti), another second-generation antipsychotic medication also modulates serotonin and dopamine levels but differs with its unique mechanism of action. Approved by the FDA in 2015 almost two decades after Olanzapine, it acts as a partial agonist at certain receptor sites which results in more balanced effects on these neurotransmitter systems. This distinct mechanism may result in fewer side effects compared to other medications that have stronger direct inhibitory or stimulatory effects on these neurotransmitters.

What conditions is Zyprexa approved to treat?

Zyprexa is approved for the treatment of several psychiatric conditions:

  • Schizophrenia
  • Acute mixed or manic episodes associated with bipolar I disorder
  • Bipolar maintenance (in combination with another drug, fluoxetine) -Rexulti on the other hand, is used in: -Major depressive disorder (as an add-on therapy to antidepressants) -Schizophrenia

How does Zyprexa help with these illnesses?

Zyprexa aids in managing conditions such as schizophrenia and bipolar disorder by altering the levels of certain natural substances in the brain. It acts on dopamine and serotonin receptors, both of which are neurotransmitters that play crucial roles in mood regulation, cognition, memory, reward systems, and more. Zyprexa blocks these receptors to a certain degree which can help balance out their overall activity. This balancing act is what helps alleviate symptoms associated with conditions like schizophrenia or bipolar disorder.

Rexulti operates similarly to Zyprexa but has slight differences. Rexulti also works by acting on dopamine and serotonin receptors; however, it doesn't just block these receptors- it also partially stimulates them at the same time. This makes Rexulti a partial agonist for these neurotransmitters -- meaning it both activates and inhibits their activity depending on the current state of the individual's brain chemistry.

Both drugs aim to restore balance among neurotransmitter systems that have gone awry due to mental health disorders – albeit through slightly differing mechanisms.

What is Rexulti?

Rexulti is a brand name for brexpiprazole, which functions primarily as a serotonin-dopamine activity modulator (SDAM), meaning it increases the levels of serotonin and dopamine in the brain by reducing their reabsorption. It also acts as a partial agonist at 5-HT1A receptors and antagonist at 5-HT2A receptors, meaning it prevents or reduces the action of these neurotransmitters at those receptors. Brexpiprazole was first approved by the FDA in July 2015. As brexpiprazole is not solely an SSRI antidepressant, its effect on other neurotransmitters like norepinephrine gives it a different side-effect profile than SSRIs such as Zyprexa - particularly that weight gain and sedation are less common with Rexulti use. The additional effects on dopamine can be beneficial for individuals with depression who do not respond well to typical SSRI antidepressants like Zyprexa.

What conditions is Rexulti approved to treat?

Rexulti has received FDA approval for the treatment of certain mental health conditions, including:

  • Major depressive disorder (MDD) as an adjunctive therapy
  • Schizophrenia

It's important to note that Rexulti is often used when other treatments haven't been effective. However, it's always crucial to discuss potential side effects and benefits with your healthcare provider before starting any new medication.

How does Rexulti help with these illnesses?

Dopamine, like norepinephrine, is a neurotransmitter that has many roles in the body. It affects emotional responses, motivation and pleasure experiences. Lower levels of dopamine are often associated with depression and other mental health disorders. Rexulti functions by adjusting these levels of dopamine available in the brain, hence helping to mitigate some symptoms of conditions such as schizophrenia or major depressive disorder (MDD). Additionally, it influences serotonin receptors which may contribute to its efficacy as an antipsychotic drug. Unlike Zyprexa which can lead to significant weight gain among other side effects, Rexulti tends to have milder side effects making it a preferred choice for patients who experience tolerance issues with drugs like Zyprexa or when used adjunctively with standard SSRI antidepressants.

How effective are both Zyprexa and Rexulti?

Both olanzapine (Zyprexa) and brexpiprazole (Rexulti) have proven efficacy in treating symptoms of schizophrenia, as well as bipolar disorder and depression, albeit they were approved by the FDA nearly two decades apart. They belong to the same atypical antipsychotic drug class but act on different neurotransmitters; hence can be prescribed under varied circumstances. A direct comparison study conducted in 2015 showed no significant difference between these two drugs' effectiveness in managing schizophrenic symptoms or their safety profiles.

A review from 2009 found that Zyprexa is effective from the first week of treatment for both positive and negative schizophrenia symptoms, with a side effect profile comparable to other atypical antipsychotics. The same study reports that it has become widely used around the world due to its robust evidentiary support. Furthermore, Zyprexa was one of the first atypical antipsychotics developed, providing a substantial history and body of research supporting its use for these conditions.

A recent meta-analysis from 2020 indicated Rexulti seems more effective than placebo in treating schizophrenia while being similar in efficacy to other common atypical antipsychotics. Yet Rexulti is often considered after first-line treatments such as risperidone or clozapine due to cost considerations or individual response variations. Notable studies involve Rexulti co-prescribed alongside an SSRI for depression management; data confirming its efficacy as a stand-alone treatment are less robust than those for Zyprexa. Nevertheless, given its unique mechanism acting primarily on serotonin receptors and partially dopamine receptors, Rexulti may be optimal for patients who did not respond well initially or prefer to avoid certain side effects associated with other typical medications.

abstract image of a researcher studying a bottle of drug.

At what dose is Zyprexa typically prescribed?

Oral dosages of Zyprexa typically range from 5–20 mg/day, but research suggests that around 10 mg/day is usually enough to manage schizophrenia in most patients. Adolescents aged 13 and older may start on a dosage as low as 2.5-5 mg/day. For both age groups, the dosage can be increased after several weeks if there's no response to treatment. However, under any circumstances the maximum daily dose should not exceed 20 mg/day.

On the other hand, for Rexulti, initial oral dosages are often around 0.5–1mg per day which might be sufficient for treating major depressive disorder when used as an adjunctive therapy with antidepressants in adults or managing symptoms of schizophrenia in adults aged above18 years old. The dosage can be slowly increased over time based on individual patient’s tolerance until an optimal therapeutic effect is achieved; however it should not exceed a maximum limit of 4mg per day.

At what dose is Rexulti typically prescribed?

Rexulti treatment is typically initiated at a dosage of 0.5-1 mg/day. Depending on the individual's response and tolerance to the medication, this dose can be increased up to 2 mg/day after one week. The recommended maintenance dose is 2 mg/day, although some patients may benefit from doses up to a maximum of 4 mg per day, divided into two doses, spaced approximately 12 hours apart. If there is no observable improvement in symptoms after several weeks of being on a consistent Rexulti dosage, your healthcare provider may consider adjusting your daily dose or exploring alternative treatments.

What are the most common side effects for Zyprexa?

Some of the most common side effects that you might experience while taking Zyprexa and Rexulti include:

  • Weight gain
  • Drowsiness (somnolence)
  • Elevated blood sugar levels
  • Constipation
  • Dry mouth
  • Abdominal discomfort or pain (dyspepsia)
  • Increased appetite
  • Fatigue or weakness (asthenia)
  • Swelling due to fluid retention
  • Tremors, restlessness, akathisia (a feeling of inner restlessness)
  • Insomnia -Anxiety, -Dizziness, -Nausea, -Decreased sexual desire and performance issues. -In rare cases, they may cause a rash or sweating.

These drugs can also increase your risk for pneumonia. If you're experiencing any unusual symptoms such as difficulty swallowing or breathing, it's essential to seek medical attention immediately.

abstract image of a patient experiencing side effect

Are there any potential serious side effects for Zyprexa?

In extreme cases, Rexulti may lead to severe side effects such as:

  • Thoughts about suicide or self-harming behavior
  • Allergic reactions including hives, difficulty breathing, swelling of your face or throat
  • Severe skin reaction: fever, sore throat, burning sensation in eyes, skin pain accompanied by a red or purple skin rash that spreads and causes blistering and peeling.
  • Vision changes like blurred vision, eye pain/swelling/redness.
  • Uncontrolled body movements (tardive dyskinesia)
  • Heart issues: fast heartbeat rate/ fluttering in chest causing shortness of breath leading to dizziness
  • Lower sodium levels - symptoms include headache, confusion, slurred speech followed by weakness/vomiting/unsteady feeling/loss of coordination. This can potentially cause a fall.
  • Neuroleptic malignant syndrome - this is characterized by high fever/sweating/confusion/fast heartbeats/stiff muscles/tremors. If you experience any of these symptoms while taking Rexulti seek immediate medical attention.

What are the most common side effects for Rexulti?

Common side effects of Rexulti can include:

  • Restlessness, agitation or feeling of needing to move around
  • Weight gain
  • Dry mouth
  • Nausea
  • Sleep problems (insomnia)
  • Dizziness
  • Constipation
  • Increased production of saliva Furthermore, as with any antipsychotic drug, some people may experience more serious side effects such as unusual mood changes and suicidal thoughts. It's important for patients taking Rexulti to monitor their symptoms closely and reach out to a healthcare provider if they notice any significant changes in mood or behavior.

Are there any potential serious side effects for Rexulti?

While Rexulti is generally well-tolerated, it's important to be aware of potential serious side effects. These may include:

  • Signs of an allergic reaction such as hives, itching, fever or swollen glands; difficulty breathing; swelling in your face or throat
  • Increased suicidal thoughts or behavior changes that are out of character for you
  • Seizures (convulsions)
  • Unusual confusion and changes in mood or behavior
  • Issues with vision such as blurred sight, tunnel-like vision, eye pain or swelling, seeing halos around lights
  • Rapid heartbeats which can cause a feeling of nervousness and restlessness
  • Potential signs indicating a manic episode: racing thoughts leading to increased energy output; exhibiting reckless behavior; experiencing feelings of extreme happiness followed by bouts of irritability; talking more than usual; severe problems with sleep

Always contact your healthcare provider if you experience any unusual symptoms while taking Rexulti.

Contraindications for Zyprexa and Rexulti?

Both Zyprexa and Rexulti, along with most other antipsychotic medications, may worsen symptoms of depression in some people. If you notice your depression worsening or an increase in suicidal ideation, thoughts, or behavior while taking these medications, please seek immediate medical attention.

Neither Zyprexa nor Rexulti should be taken if you are taking certain types of drugs like selective serotonin reuptake inhibitors (SSRIs), tricyclic antidepressants (TCAs) and certain anti-arrhythmic drugs. Always inform your healthcare provider about all the medications you are currently using; these substances will require a suitable washout period to clear from the system to prevent dangerous interactions with Zyprexa and Rexulti.

How much do Zyprexa and Rexulti cost?

For the brand name versions of these medications:

  • The price for 30 tablets of Rexulti (1mg) averages around $1150, which works out to approximately $38/day.
  • On the other hand, Zyprexa costs about $800 for a similar quantity and strength (30 tablets of 2.5 mg), working out to roughly $26/day.

Thus, if you are in the higher dosage range for Rexulti (i.e., 3 mg/day or higher), then brand-name Zyprexa is less expensive on a per-day treatment basis. Please remember that cost should not be your sole consideration in determining which of these drugs is right for you.

As for their generic versions, brexpiprazole and olanzapine:

  • Brexpiprazole comes in packs from 7 up to 90 tablets with approximate costs ranging between $35 - $400 depending on pack size and dose range.
  • Olanzapine is available in larger quantities starting from packs as small as ten up to several hundred. Costs can vary significantly but are generally lower than its branded counterpart – starting at just over a dollar per day, potentially rising depending on dose or tablet count purchased.

Popularity of Zyprexa and Rexulti

Olanzapine, in generic form as well as brand names such as Zyprexa, was estimated to have been prescribed to about 2.4 million people in the US in 2020. Olanzapine accounted for just over 14% of atypical antipsychotic prescriptions in the US. It is often used for the treatment of schizophrenia and bipolar disorder, and its use has been generally stable since it hit the market.

Brexpiprazole, including brand versions such as Rexulti, was prescribed to approximately 600 thousand people in the USA in 2020. In the US, brexpiprazole accounts for just under 3% of atypical antipsychotic prescriptions - a number that has been gradually increasing since its approval by FDA back in July 2015. Though newer on scene than olanzapine and less common so far, brexpiprazole is also primarily used for managing symptoms of schizophrenia but additionally approved alongside an antidepressant medication to treat adults with major depressive disorder (MDD).


Both Zyprexa (olanzapine) and Rexulti (brexpiprazole) have been utilized extensively in the treatment of schizophrenia and bipolar disorder, with considerable clinical studies indicating their efficacy over placebo treatments. Occasionally, these drugs may be used together under scrupulous observation by a medical professional as they can interact with one another. They possess different mechanisms of action: Zyprexa primarily acts as an antagonist at dopamine and serotonin receptors, while Rexulti works mainly as a partial agonist at dopamine D2 receptors and serotonin 5-HT1A receptors.

Zyprexa is often considered a first-line option for acute manic or mixed episodes in bipolar disorder whereas Rexulti may typically be used as an add-on therapy to antidepressants for major depressive disorder or in patients who did not respond well to initial antipsychotic medications.

Both medicines are available in generic forms which provide significant economic benefits especially for those paying out-of-pocket. It's important to note that both Zyprexa and Rexulti might require some time before their full effects become noticeable.

The side effect profiles of both drugs are relatively similar; however, weight gain tends to be more pronounced with Zyprexa use compared to Rexulti. Patients must closely monitor any changes in mood or behavior when initiating these therapies since worsening symptoms or emergence of suicidal ideation should prompt immediate medical attention.