Symbyax is a combination of two medications: olanzapine (an atypical antipsychotic) and fluoxetine (a selective serotonin reuptake inhibitor (SSRI). It's used to treat depressive episodes of bipolar 1 disorder in adults and children ages 10 years and older, as well as treatment-resistant depression in adults. Symbyax (olanzapine / fluoxetine) comes as capsules that are taken by mouth once per day. Some side effects include sleepiness, weight gain, and dry mouth. Symbyax is available as brand-name and generic medications.
Depressive episodes of bipolar 1 disorder in adults and children ages 10 years and older
Treatment-resistant depression in adults
Symbyax contains two medications that work together to help with mood:
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.
Fluoxetine is a selective serotonin reuptake inhibitor (SSRI). It works mainly by raising the levels of serotonin to help manage your mood and emotions.
Source:Â DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
More common
Bloating or swelling of the face, arms, hands, lower legs, or feet
body aches or pain
confusion
congestion
delusions
dryness or soreness of the throat
hoarseness
rapid weight gain
shakiness in the legs, arms, hands, or feet
tender, swollen glands in the neck
tingling of the hands or feet
trembling or shaking of the hands or feet
trouble with swallowing
unusual weight gain or loss
voice changes
Less common
Blurred vision
change in personality
change in vision
difficult or labored breathing
difficulty with sleeping
difficulty with speaking
dizziness
ear pain
headache
impaired vision
increase in body movements
loss of memory
nervousness
pounding in the ears
problems with memory
slow, fast, pounding, or irregular heartbeat or pulse
tightness in the chest
Rare
Inability to move the eyes
increased blinking or spasms of the eyelid
sticking out of the tongue
uncontrolled twisting movements of the neck, trunk, arms, or legs
unusual facial expressions
Incidence not known
Bloody or black, tarry stools
severe stomach pain
vomiting of blood or material that looks like coffee grounds
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Less common
Change or problem with discharge of semen
decreased interest in sexual intercourse
difficulty with moving
inability to have or keep an erection
loss in sexual ability, desire, drive, or performance
muscle pain or stiffness
not able to have an orgasm
pain, swelling, or redness in the joints
tooth disorder
twitching
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Conveniently combines two medications in one pill
Taken once daily
Can be taken with or without food
An option for children ages 10 years and older (in bipolar disorder)
Can lower blood pressure (orthostatic hypotension), which raises risk of falls
Stopping too suddenly can lead to withdrawal symptoms, like dizziness and nausea
Drinking alcohol at the same time can worsen sleepiness
Can cause sexual problems as side effects
It's best to take Symbyax (olanzapine / fluoxetine) in the evening. Because this medication 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.
Symbyax (olanzapine / fluoxetine) 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.
Symbyax (olanzapine / fluoxetine) 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.
Symbyax (olanzapine / fluoxetine) might worsen suicidal thoughts. Contact your psychiatrist right away if you or your loved ones notice any new or worsening changes in your behavior or mood while taking the medication.
Don't suddenly stop taking Symbyax (olanzapine / fluoxetine) without talking to your prescriber first. Doing so can cause withdrawal symptoms, such as anxiety and balance issues. If you want to stop the medication, your healthcare team can help you do so safely by lowering your dose slowly over time.
Both olanzapine and fluoxetine interact with many medications. Tell your care team about all of the medications you're taking before starting Symbyax (olanzapine / fluoxetine) so they can help you check for interactions.
Let your psychiatrist know if you're pregnant or thinking of becoming pregnant. They can talk with you about the benefits and risks of taking Symbyax (olanzapine / fluoxetine) during pregnancy, as well as other treatment options. This is important because untreated mental health conditions during pregnancy can be harmful for you and your baby.
Olanzapine and fluoxetine in Symbyax can get into breastmilk. This can cause side effects in breastfed babies, such as fussiness and sleepiness. Let your psychiatrist know if you're breastfeeding. They'll discuss with you the risks and benefits of continuing Symbyax (olanzapine / fluoxetine).
Symbyax (olanzapine / fluoxetine) 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 under 24 years old | History of depression or other mental health conditions
Taking Symbyax (olanzapine / fluoxetine) might raise the risk of worsening depression and thoughts of self-harm. If you or anyone around you notice that you have suicidal thoughts or unusual behavior (e.g., anxiety, panic attacks, difficulty sleeping, feeling angry or irritated, restlessness) while taking Symbyax (olanzapine / fluoxetine), get medical help right away.
Risk factors: Age 65 years and older with dementia and psychosis
People 65 years and older with dementia sometimes have symptoms of schizophrenia, like delusions and hallucinations (believing, seeing, or hearing things that aren't real). This is called dementia-related psychosis. Older people with dementia-related psychosis have a high risk of death if they take antipsychotic medications like olanzapine in Symbax. Because of this risk, Symbyax (olanzapine / fluoxetine) shouldn't be taken by older adults with dementia-related psychosis. Let your prescriber know if you or your loved one has dementia before starting Symbyax (olanzapine / fluoxetine).
Taking antipsychotic medications like olanzapine in Symbax can cause a rare, but life-threatening condition called neuroleptic malignant syndrome. 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 Symbyax (olanzapine / fluoxetine), get medication attention as soon as possible. Your prescriber will likely have you stop taking Symbyax (olanzapine / fluoxetine) and switch you to something else.
Risk factors: Taking high doses of Symbyax (olanzapine / fluoxetine) | Age 65 years or older | Drinking alcohol | Taking other medications that can cause sleepiness
Symbyax (olanzapine / fluoxetine) 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 Symbyax (olanzapine / fluoxetine).
Although rare, Symbyax (olanzapine / fluoxetine) 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 Symbyax (olanzapine / fluoxetine) and get medical attention right away.
Risk factors: Diabetes | High cholesterol | Obesity
Olanzapine in Symbyax can raise your blood sugar and cholesterol levels as well as raise your appetite, all of which can lead to weight gain. Your prescriber might order blood tests regularly throughout treatment with Symbyax (olanzapine / fluoxetine) to make sure your blood sugar and cholesterol aren't too high. Make sure to have a healthy and balanced diet low in fat and sugar and maintain a regular exercise routine while taking Symbyax (olanzapine / fluoxetine).
Risk factors: Taking other medications that raise serotonin levels in your brain
Some people taking Symbyax (olanzapine / fluoxetine) have developed a rare, but potentially life-threatening condition called serotonin syndrome. This condition happens where there's too much serotonin in the brain. Your risk for serotonin syndrome is higher if you take Symbyax (olanzapine / fluoxetine) with other medications that can raise your serotonin levels, such as certain antidepressants, mental health medications, pain medications, and migraine medications. Let your psychiatrist know about all the medications you take before starting Symbyax (olanzapine / fluoxetine). Also, don't start any new medications without talking to your psychiatrist first. Symptoms of serotonin syndrome include fast heart rate, sweating, muscle stiffness or spasms, fever, and confusion. Get medical help right away if you have any of these symptoms.
Risk factors: History of angle-closure glaucoma
Symbyax (olanzapine / fluoxetine) can lead to or worsen angle-closure glaucoma. You might need to see your optometrist regularly and get eye exams to check your eyes and make sure your vision isn't worsening. Contact your optometrist or psychiatrist if you notice changes in your vision after starting Symbyax (olanzapine / fluoxetine).
Olanzapine in Symbyax can cause uncontrolled body movements, such as eye-twitching or lip-smacking. This is more likely to happen the longer you take medications like Symbyax (olanzapine / fluoxetine). 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: Taking blood-thinners or other medications that raise your risk of bleeding
Fluoxetine in Symbyax (olanzapine / fluoxetine) can raise your risk of severe bleeding or bruising, especially if you're also taking antiplatelets (e.g., aspirin, clopidogrel (Plavix)) or anticoagulants (e.g., warfarin (Coumadin), apixaban (Eliquis), rivaroxaban (Xarelto)). Get medical help if you get bruising that doesn't improve, black-colored stools, pink or red-colored urine, coughing up or vomiting blood, or unusual bleeding from the nose or gums.
Risk factors: History of low blood cell counts
Though not common, olazapine in Symbyax can lower your white blood cell (WBC) counts, especially if you already have low WBC levels from other medical conditions. This can raise your risk of serious infection. You'll need to get blood tests done regularly during the first few months of taking Symbyax (olanzapine / fluoxetine) so your prescriber can make sure your blood cell counts are in the normal range. If your WBC levels drop too low, you'll likely need to stop taking Symbyax (olanzapine / fluoxetine). If you develop any signs of infection, such as fever, tiredness, chills, cough, or trouble breathing, and they don't go away, contact your prescriber right away.
Risk factors: Older adults | Taking diuretic medications
Though rare, fluoxetine in Symbyax can cause low blood sodium levels. Your prescriber might closely monitor your blood sodium levels before and during treatment with Symbyax (olanzapine / fluoxetine). Get medical help right away if you experience weakness, confusion, difficulty concentrating, headache, or memory problems because these could be signs of low blood sodium levels, which is a medical emergency.
Risk factors: Low blood potassium or magnesium levels | Older age | Kidney problems | History of heart problems, slow heart rate, or other abnormal heart rhythms (arrhythmias) | Personal or family history of long QT syndrome | Taking other medications that cause QT prolongation
Fluoxetine in Symbyax can can cause a serious heart rhythm problem called QT prolongation. You're at higher risk for this problem if you're taking other medications that cause heart rhythm problems, such as amiodarone (Pacerone). Because people who have QT prolongation typically don't experience symptoms, your psychiatrist or primary care provider might periodically monitor your heart with electrocardiograms (EKGs), if needed. If you feel your chest pounding, have shortness of breath, have chest pain, or feel faint or lightheaded while taking Symbyax (olanzapine / fluoxetine), call 911 right away.
Olanzapine in Symbyax 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 Symbyax (olanzapine / fluoxetine), ask your healthcare team to help you check for medication interactions.
Antipsychotics like olanzapine in Symbyax can raise the levels of prolactin in your body. High prolactin can lead to fertility problems, enlarged male breasts, sexual dysfunction, and absence or irregular menstrual periods. Your healthcare professional will likely measure your prolactin levels during treatment to make sure they aren't too high.
Adults
Depressive episodes of bipolar 1 disorder and treat-resistant depression: The typical starting dose for Symbyax is 6 mg/25 mg (olanzapine/fluoxetine) by mouth once per day in the evening. The maximum dose is 18 mg/75 mg (olanzapine/fluoxetine) per day.
Children ages 10 years and older
Depressive episodes of bipolar 1 disorder: The typical starting dose for Symbyax is 3 mg/25 mg (olanzapine/fluoxetine) by mouth once a day in the evening. The maximum dose is 12 mg/50 mg (olanzapine/fluoxetine) per day.
Your dose might differ if you have a higher risk of low blood pressure, have liver problems, are female, are non-smoking, or 65 years or older.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Taking MAOIs, linezolid (Zyvox), or methylene blue (ProvayBlue), within 5 weeks of stopping treatment with Symbyax (olanzapine / fluoxetine), or within 14 days of stopping an MAOI, linezolid (Zyvox), or methylene blue (ProvayBlue)
Taking pimozide or thioridazine at the same time
Depressive episodes of bipolar 1 disorder in adults and children ages 10 years and older
Treatment-resistant depression in adults
Treatment of manic episodes of bipolar disorder
Long-term maintenance treatment of bipolar disorder
Schizophrenia in adults and children age 13 years and older
Bipolar disorder in adults and children age 10 years and older
Add-on to antidepressants for depression (extended-release only)
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Tohen, M., et al. (2003). Efficacy of olanzapine and olanzapine-fluoxetine combination in the treatment of bipolar I depression. Archives of General Psychiatry.
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