Lybalvi is the brand name for the combination medication containing olanzapine (an atypical antipsychotic) and samidorphan (an opioid antagonist). It’s used to treat schizophrenia and bipolar I disorder in adults. It comes as a tablet that's taken by mouth once per day. Lybalvi (olanzapine / samidorphan) causes less weight gain than olanzapine (Zyprexa), but it's still a common side effect. Other side effects include sleepiness, dry mouth, and headache.
Schizophrenia in adults
Bipolar 1 disorder in adults
Lybalvi is a combination of two medications that work together:
Olanzapine is an atypical antipsychotic. It's thought to balance the levels of certain chemicals (dopamine and serotonin) in the brain. This can help control thoughts, mood, and behaviors.
Samidorphan is an opioid antagonist. It doesn't play a role in managing schizophrenia or bipolar disorder symptoms. Instead, it helps prevent weight gain, which is a common side effect of olanzapine.
Source: DailyMed
Side effects that you should report to your care team as soon as possible:
Side effects that usually do not require medical attention (report these to your care team if they continue or are bothersome):
Lower risk of weight gain compared to olanzapine (Zyprexa)
Taken by mouth once per day
Combines two medications into one pill for convenience
Can cause sleepiness
Might trigger opioid withdrawal if you've recently taken opioid medications
For adults only
You can take Lybalvi (olanzapine / samidorphan) once a day with or without food. If it causes stomach upset, taking the medication with food can help.
Swallow Lybalvi (olanzapine / samidorphan) tablet whole. Don’t split, crush, or chew the tablets. If you're having trouble swallowing the medication, let your prescriber know. You'll likely need to be switched to a different medication.
You can take Lybalvi (olanzapine / samidorphan) at any time of day. But you might consider taking it in the evening since it can make you sleepy and dizzy. Taking it closer to bedtime can make these side effects less bothersome during the day. Don't drive or do anything that needs a lot of focus or attention until you know how this medication affects you.
Lybalvi (olanzapine / samidorphan) can make you feel dizzy or faint, which can lead to falls. To lower this risk, get up slowly and hold onto something when you're trying to stand from a sitting or lying position.
Lybalvi (olanzapine / samidorphan) can make it harder for your body to cool down if your body temperature gets too high. This makes it more likely for you to become dehydrated and your body to overheat. It's important to drink enough water to stay hydrated when you're taking this medication. Avoid spending extended time outside when it's hot. Get medical help if you have symptoms of heat exhaustion, including muscle cramps, nausea, and headache.
Lybalvi (olanzapine / samidorphan) can interact with certain medications. For example, samidorphan in Lybalvi is an opioid blocker and you can't take this medication with any opioid medications. Doing so can trigger severe opioid withdrawal symptoms. Tell your care team about all of the medications you're taking before starting Lybalvi (olanzapine / samidorphan) so they can help you check for interactions.
Lybalvi (olanzapine / samidorphan) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: Age 65 years and older with dementia and psychosis
Older adults with dementia might sometimes experience symptoms similar to schizophrenia, such as hallucinations and delusions. This condition is known as dementia-related psychosis, and it should not be treated with Lybalvi (olanzapine / samidorphan). Research suggests that taking antipsychotic medications to manage dementia-related psychosis increases the risk of life-threatening complications, including heart problems, stroke, and infections. Let your prescriber know if you or your loved one has dementia before starting Lybalvi (olanzapine / samidorphan).
Risk factors: Physical dependence on opioid medications
Lybalvi contains samidorphan, which is a medication that blocks the effect of opioid medications like oxycodone (Roxicodone), Percocet (oxycodone / acetaminophen), and Norco (hydrocodone / acetaminophen. Taking Lybalvi (olanzapine / samidorphan) can cause opioid withdrawal in people who are physically dependent on opioids. This can cause symptoms such as restlessness, anxiety, teary eyes, frequent yawning, widened pupils, runny nose, vomiting, and seizures. Because of this risk, you shouldn't take Lybalvi (olanzapine / samidorphan) if you are currently taking opioid medications or if you've recently stopped taking opioids and are undergoing opioid withdrawal. Depending on the opioid you were taking, you should wait at least 7 to 14 days between stopping an opioid and starting Lybalvi (olanzapine / samidorphan).
Lybalvi contains samidorphan, a medication that reverses the effects of opioids. Taking high or repeated doses of opioid medications to try to counteract the effect of samidorphan can lead to life-threatening opioid overdose, especially if you've recently missed doses or stopped taking Lybalvi (olanzapine / samidorphan). Signs of an overdose include extremely slowed breathing, excessive sleepiness, and even death. If you were previously taking opioids and plan to restart them after taking Lybalvi (olanzapine / samidorphan), your tolerance might be lower than it was, meaning continuing opioids at your previous dose can raise your risk of an overdose. Follow your prescriber's instructions for how to restart opioids.
Although rare, Lybalvi (olanzapine / samidorphan) can cause serious skin reactions, such as Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS). If you notice changes in your skin (e.g., rash, blisters, swollen lymph nodes, skin reddening, skin peeling) or experience swelling in your face or trouble breathing, stop using Lybalvi (olanzapine / samidorphan) and get medical attention right away.
Taking antipsychotic medications like Lybalvi (olanzapine / samidorphan) can cause a rare, but life-threatening condition called neuroleptic malignant syndrome. Some symptoms include fever, sweating, stiff muscles, confusion, not aware of your surroundings, and fast or irregular heartbeat. If you experience any of these symptoms while taking Lybalvi (olanzapine / samidorphan), get medication attention as soon as possible. Your prescriber will likely have you stop taking Lybalvi (olanzapine / samidorphan) and switch you to something else.
Risk factors: Diabetes | High cholesterol | Identified as obese
Lybalvi (olanzapine / samidorphan) can raise your blood sugar and cholesterol levels as well as raise your appetite, all of which can lead to weight gain. Your prescriber will likely order blood tests regularly throughout treatment with Lybalvi (olanzapine / samidorphan) to make sure your blood sugar and cholesterol aren't too high. Make sure to have a balanced diet low in fat and sugar and maintain a regular exercise routine while taking Lybalvi (olanzapine / samidorphan).
Risk factors: Female | Older adults
Taking antipsychotic medications like Lybalvi (olanzapine / samidorphan) can cause uncontrolled body movements (tardive dyskinesia), such as eye-twitching or lip-smacking. This is more likely to happen the longer you take medications like Lybalvi (olanzapine / samidorphan). This can become permanent if it's not caught in time. If you experience any uncontrolled movements and aren't able to stop them, talk to your healthcare professional right away.
Risk factors: Low blood pressure | Taking medications that lower blood pressure | History of medical conditions that can lower blood pressure | High Lybalvi (olanzapine / samidorphan) doses
Lybalvi (olanzapine / samidorphan) can make you tired, lower your blood pressure, or cause you to lose your balance, which can lead to falls. The risk is higher when you first start this medication or whenever your prescriber raises the dose. When standing from a sitting or lying position, make sure to get up slowly and hold onto something. If you experience a fall while taking Lybalvi (olanzapine / samidorphan), contact your healthcare professional.
Risk factors: History of low blood cell counts
Though rare, Lybalvi (olanzapine / samidorphan) can lower your white blood cell counts (WBCs) and put you at risk for developing infections. If you already have low WBC levels, your care team will order blood tests regularly during the first few months of treatment to check if your WBC levels are within a safe range. If your WBC count drops too low, you'll likely need to stop taking Lybalvi (olanzapine / samidorphan). If you develop any signs of infection, such as fever, tiredness, chills, cough, or trouble breathing, and they don't go away, contact your healthcare professional right away.
Risk factors: History of seizures | Health conditions that make it easier to get seizures
Lybalvi (olanzapine / samidorphan) can potentially cause seizures. Before starting this medication, let your healthcare professional know if you have a history of seizures or have a medical condition that puts you at risk for getting seizures.
Antipsychotics like olanzapine in Lybalvi can raise the levels of a hormone called prolactin in your body. The risk is higher if you take this medication over a longer period of time. High prolactin levels might lead to fertility problems, enlarged male breasts, sexual problems, absence or irregular menstrual periods, and weak bones. Your healthcare professional might order blood work to check your prolactin levels when you're taking Lybalvi (olanzapine / samidorphan). Talk with your healthcare team if you're concerned about problems linked to higher prolactin levels.
Risk factors: Taking high doses of Lybalvi (olanzapine / samidorphan) | Age 65 years or older | Drinking alcohol | Taking other medications that can cause sleepiness
Lybalvi (olanzapine / samidorphan) can cause extreme sleepiness and lower your ability to think, react, and focus. Your risk is higher if you're also taking other medications that can cause drowsiness, such as benzodiazepines, anxiety medications, muscle relaxants, and sleep medications. Make sure you know how this medication affects you before driving a car or doing activities that require your concentration. Talk to your healthcare professional right away if you feel too sleepy from taking Lybalvi (olanzapine / samidorphan).
Olanzapine in Lybalvi might cause anticholinergic side effects, including trouble urinating, constipation, and bowel movement problems. The risk of these side effects are higher if you're taking other anticholinergic medications, such as certain ones for treating overactive bladder or motion sickness. Before starting Lybalvi (olanzapine / samidorphan), ask your healthcare team to help you check for medication interactions.
Lybalvi (olanzapine / samidorphan) can sometimes make it hard for you to swallow food or liquids. This can be dangerous if food or liquids get into your lungs, because it can cause issues with your breathing and infections. Make sure to chew your food completely and swallow carefully if you notice tightening of your throat or neck area.
Your psychiatrist will determine your dose of Lybalvi (olanzapine / samidorphan) based on your condition, how well the medication is helping your symptoms, and if you're having side effects.
Schizophrenia: The typical starting dose is 5 mg/10 mg (olanzapine / samidorphan) or 10 mg/10 mg (olanzapine / samidorphan) by mouth once daily.
Bipolar I disorder (if taken alone): The typical starting dose is 10 mg/10 mg (olanzapine / samidorphan) or 15 mg/10 mg (olanzapine / samidorphan) by mouth once daily.
Bipolar I disorder (if taken in combination with lithium (Lithobid) or valproate (Depakote)): The typical starting dose is 10 mg/10 mg (olanzapine / samidorphan) by mouth once daily.
The maximum total dose of Lybalvi (olanzapine / samidorphan) is 20 mg/10 mg (olanzapine/samidorphan) once daily.
Currently taking opioids
Experiencing withdrawal symptoms from stopping opioid medications
Schizophrenia in adults
Bipolar 1 disorder in adults
Schizophrenia in adults and children age 13 years and older
Bipolar I disorder in adults and children age 13 years and older
Bipolar depression in adults and children age 10 years and older
Depression that hasn't responded well to other treatments
Tourette syndrome in children
Depression (add-on treatment)
Irritability associated with autistic disorder in children
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Corrao, M. M., et al. (2022). Olanzapine/samidorphan: A new combination treatment for schizophrenia and bipolar I disorder intended to reduce weight gain. CNS Drugs.
Gao, J., et al. (2022). Samidorphan for the treatment of weight gain associated with olanzapine in patients with schizophrenia and bipolar disorder. Expert Review of Clinical Pharmacology.
Patel, K. R., et al. (2014). Schizophrenia: Overview and treatment options. Pharmacy and Therapeutics.
Rehan, S. T., et al. (2022). Samidorphan/olanzapine combination therapy for schizophrenia: Efficacy, tolerance and adverse outcomes of regimen, evidence-based review of clinical trials. Annals of Medicine and Surgery.
Simon, L. V., et al. (2023). Neuroleptic malignant syndrome. StatPearls.
You and Your Hormones. (2023). Prolactin.
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