Symbyax is a combination of two prescription medications that is used to treat the symptoms of depressive episodes associated with bipolar I disorder.

It is a single product containing 2 medications: olanzapine and fluoxetine. Olanzapine belongs to a group of drugs called antipsychotics. These work by changing the activity of certain natural substances in the brain. Fluoxetine belongs to a group of drugs called selective serotonin reuptake inhibitors (SSRIs). These work by increasing the amount of serotonin, a natural substance in the brain that helps maintain mental balance.

This medication comes in an oral (by mouth) capsule form and is taken typically once a day, with or without food, at bedtime.

Common side effects of Symbyax include dry mouth, tiredness, increased appetite, and tremors (shakes). Symbyax can also cause dizziness, drowsiness, and blurred vision. Do not drive or operate heavy machinery until you know how Symbyax affects you.


Suicidality and Antidepressant Drugs — Antidepressants increased the risk compared to placebo of suicidal thinking and behavior (suicidality) in children, adolescents, and young adults in short-term studies of Major Depressive Disorder (MDD) and other psychiatric disorders. Anyone considering the use of Symbyax or any other antidepressant in a child, adolescent, or young adult must balance this risk with the clinical need. Short-term studies did not show an increase in the risk of suicidality with antidepressants compared to placebo in adults beyond age 24; there was a reduction in risk with antidepressants compared to placebo in adults aged 65 and older. Depression and certain other psychiatric disorders are themselves associated with increases in the risk of suicide. Patients of all ages who are started on antidepressant therapy should be monitored appropriately and observed closely for clinical worsening, suicidality, or unusual changes in behavior. Families and caregivers should be advised of the need for close observation and communication with the prescriber. Symbyax is not approved for use in pediatric patients.

Increased Mortality in Elderly Patients with Dementia-Related Psychosis — Elderly patients with dementia-related psychosis treated with antipsychotic drugs are at an increased risk of death. Analyses of seventeen placebo-controlled trials (modal duration of 10 weeks), largely in patients taking atypical antipsychotic drugs, revealed a risk of death in drug-treated patients of between 1.6 to 1.7 times the risk of death in placebo-treated patients. Over the course of a typical 10-week controlled trial, the rate of death in drug-treated patients was about 4.5%, compared to a rate of about 2.6% in the placebo group. Although the causes of death were varied, most of the deaths appeared to be either cardiovascular (e.g., heart failure, sudden death) or infectious (e.g., pneumonia) in nature. Observational studies suggest that, similar to atypical antipsychotic drugs, treatment with conventional antipsychotic drugs may increase mortality. The extent to which the findings of increased mortality in observational studies may be attributed to the antipsychotic drug as opposed to some characteristic(s) of the patients is not clear. Symbyax (olanzapine and fluoxetine HCl) is not approved for the treatment of patients with dementia-related psychosis.


Review Date: 
August 22, 2012
Long Title: 
Symbyax is used to treat depression associated with bipolar disorder. Take this medication in the evening to reduce your chance of being sleepy during the daytime.
Black Box Warning Image: 
Uses : 

Symbyax is a prescription medication used to treat symptoms of depressive episodes associated with bipolar I disorder.

This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.

Side Effects: 

Serious side effects have been reported with Symbyax. See the "Symbyax Precautions" section.

Common side effects of Symbyax include the following:

  • dry mouth
  • tiredness
  • increased appetite
  • swelling of the hands and feet
  • drowsiness
  • tremors (shakes)
  • blurred vision
  • weight gain
  • diarrhea
  • increased sweating

This is not a complete list of Symbyax side effects. Ask your doctor or pharmacist for more information.

Tell your doctor if you have any side effect that bothers you or that does not go away.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

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Drug Interactions: 

Tell your doctor about all the medicine you take, including prescription and non-prescription medicines, vitamins, and herbal supplements. Especially tell your doctor if you take:

  • monoamine oxidase inhibitors (MAOIs) such as tranylcypromine (Parnate), phenelzine (Nardil), selegiline (Eldepryl, Zelapar), isocarboxazid (Marplan), and rasagiline (Azilect)
  • selective serotonin reuptake inhibitors (SSRIs) such as escitalopram (Lexapro), sertraline (Zoloft), citalopram (Celexa), vilazodone (Viibryd), paroxetine (Paxil), and fluvoxamine (Luvox)
  • antipsychotics such as paliperidone (Invega), lurasidone (Latuda), aripiprazole (Abilify), asenapine (Saphris), iloperidone (Fanapt), haloperidol (Haldol), prochlorperazine (Compazine), chlorpromazine (Thorazine), clozapine (Klonopin), risperidone (Risperdal), quetiapine (Seroquel), and ziprasidone (Geodon)
  • Drugs that can cause an arrhythmia called Torsades de Point such as:
    • certain anti-arrythmia medications including procainamide, sotalol (Betapace), quinidine (Nuedexta), dofetilide (Tikosyn), amiodarone (Nexterone, Pacerone, Cordarone), ibutilide (Corvert)
    • certain fluoroquinolone antibiotics including levofloxacin (Levaquin), ciprofloxacin (Cipro), gatifloxacin (Zymar), moxifloxacin (Avelox)
    • certain macrolide antibiotics including clarithromycin (Biaxin), erythromycin (EES, others)
    • certain azole antifungals including ketoconazole (Nizoral), itraconazole (Sporanox, Onmel)
    • certain antidepressants including amitriptyline, desipramine (Norpramin), imipramine (Tofranil, Surmontil), doxepin (Silenor), sertraline (Zoloft), venlafaxine (Effexor XR)
    • certain antipsychotics including haloperidol (Haldol), droperidol (Inapsine), quetiapine (Seroquel XR), thioridazine, ziprasidone (Geodon)
    • other medications including cisapride, sumatriptan (Treximet, Imitrex, Alsuma, Zecuity), zolmitriptan (Zomig, arsenic (Trisenox), dolasetron (Anzemet), and methadone (Methadone, Dolophine)
  • medications that could lead to serotonin syndrome such as citalopram (Celexa), escitalopram (Lexapro), fluvoxamine (Luvox), desvenlafaxine (Pristiq), nefazodone (Serzor), paroxetine (Paxil, Pexeva), sertraline (Zoloft), venlafaxine (Effexor), trimipramine (Surmontil), isocarboxazid (Marplan), amitriptyline (Elavil), nortriptyline (Pamelor, Aventyl), protriptyline (Vivactil), and clomipramine (Anafranil), and linezolid (Zyvox)
  • anticholinergics such as glycopyrrolate (Cuvposa, Robinul), trospium (Sanctura), oxybutynin (Anturol, Gelnique, Oxytrol, Ditropan), solifenacin (Trospium), dicyclomine (Bentyl), propantheline (Pro-Banthine), and atropine (Atropen, Sal-Tropine)
  • anticoagulant (blood thinner) medications such as warfarin (Coumadin, Jantoven), heparin, enoxaparin (Lovenox), fondaparinux (Arixtra), rivaroxaban (Xarelto), and apixaban (Eliquis)
  • aspirin and other NSAIDs (nonsteroidal anti-inflammatory drugs) such as
    • celecoxib (Celebrex)
    • diclofenac (Cambia, Cataflam, Flector, Voltaren, Zipsor and others)
    • etodolac (Lodine)
    • ibuprofen (Advil, Motrin, Nuprin)
    • indomethacin (Indocin, Indocin SR)
    • ketoprofen (Orudis, Actron, Oruvail)
    • ketorolac (Toradol)
    • meloxicam (Mobic)
    • nabumetone (Relafen)
    • naproxen (Naprosyn)
    • naproxen sodium (Aleve, Anaprox, Naprelan)
    • oxaprozin (Daypro)
    • piroxicam (Feldene)
  • alcohol
  • benzodiazepines such as diazepam (Valium), alprazolam (Xanax), lorazepam (Ativan), and clonazepam (Klonopin)
  • certain anti-seizure medications such as carbamazepine (Tegretol), phenytoin (Dilantin), valproic acid (Depakote)
  • medications that block a protein in the body (CYP2D6) such as quinidine (Qualaquin), amitriptyline (Elavil, Amitril, Amitid), and paroxetine (Paxil)
  • medications that use the enzyme CYP2D6 such as desipramine (Norpramin), dextromethorphan (Delsym), atomoxetine (Strattera), flecainide (Tambocor), and propafenone (Rythmol)
  • medications that you are on to lower your blood pressure
  • anti-parkinson's medications including levodopa, carbidopa, and pramipexole (Mirapex)
  • anti-arrhythmia medications such as procainamide (Procanbid, Procan), disopyramide (Norpace, Rythmodan), lidocaine (Xylocaine, Lidoderm), phenytoin (Dilantin), mexilitine (Mexitil), flecainide (Tambocor), propafenone (Rythmol), amiodarone (Cordarone, Pacerone), sotalol (Betapace), dofetilide (Tikosyn), dronedarone (Multaq), digoxin (Lanoxin), and adenosine (Adenocard)
  • pimozide (Orap)
  • thioridazine

This is not a complete list of Symbyax drug interactions. Ask your doctor or pharmacist for more information.

Drug Precautions: 

Serious side effects have been reported with Symbyax including the following:

  • increased risk for suicidal thoughts or behaviors. You should be closely monitored for any changes in mood or behavior by your physician and family members.
  • neuroleptic malignant syndrome. Symptoms of neurolpetic syndrome may include fever, rapid or abnormal heart beat, sweating, confusion, and muscle rigidity. Seek emergency medical attention if you experience any of these symptoms.
  • hyperglycemia (high blood sugar). Prolonged elevated blood sugar over time may lead to diabetes and complications from diabetes. Your doctor should do blood tests to test you for diabetes. Tell your doctor if you are urinating more frequently, have an increased appetite, or experience increased thirst. 
  • hyperlipidemia (high amounts of (fats) lipids). This can lead to increased risk of cardiovascular (heart) problems. Your doctor should do blood tests to check the levels of fats in your blood.
  • serotonin syndrome. This occurs when too much serotonin builds up in your body. Symptoms of serotonin syndrome include increased sweating, rapid heartbeat, skin redness, difficulty breathing, confusion, restlessness, and tremors (shaking). Seek emergency medical attention if you experience any of these symptoms.
  • decreased blood counts. Olanzapine may reduce the amount of white blood cells in your body to fight off infections. Tell your doctor if you have a sore throat, fever, chills, or other signs of infection.
  • sexual dysfunction. Fluoxetine may lead to changes in sexual functioning, including decreased libido, erectile dysfunction, and prolonged erections.
  • QT prolongation. QT prolongation is a condition that may lead to a dangerous type of irregular heartbeat. Call your doctor right away if you experience a rapid heartbeat, an extremely strong heartbeat, or dizziness.
  • dystonia. This refers to spasms of the muscle that do not go away for a prolonged period of time.
  • gastritis. This refers to swelling of the stomach. Symptoms of gastritis may include abdominal pain, nausea, and vomiting.
  • gastrointestinal hemorrhage. In some cases, damage to the intestines can become so severe that bleeding may occur. Seek emergency medical treatment if you notice any severe abdominal pain.
  • pancreatitis. Symptoms of pancreatitis include nausea, vomiting, and abdominal pain that radiates to the back.
  • weight loss. Although olanzapine most commonly leads to weight gain, it may cause weight loss in rare cases.
  • menorrhagia. Symptoms of menorrhagia include very heavy menstrual bleeding or bleeding that lasts longer than normal. Tell your doctor if you experience any changes in your menstrual cycle.
  • angle-closure glaucoma. This is a condition where the fluid is suddenly blocked and unable to flow out of the eye causing a quick, severe increase in eye pressure which may lead to a loss of vision. Your doctor should do an eye exam before starting fluoxetine. If you have nausea, eye pain, changes in vision, such as seeing colored rings around lights, and swelling or redness in or around the eye, call your doctor or get emergency medical treatment right away.
  • orthostatic hypotension. This refers to a drop in blood pressure upon standing from a sitting or lying down position. You may feel faint, light-headed, or dizzy upon standing. Get up more slowly until you know how this medication affects you.
  • joint pain. Call your doctor if you have joint pain.
  • rash or hives. Call your doctor if you develop a rash or hives.
  • seizures. Call your doctor if you have a seizure.
  • difficulty breathing or swallowing. Seek emergency medical attention if you have trouble breathing or swallowing.
  • liver problems. Tell your doctor if you have ever had liver disease.
  • hyponatremia (low sodium levels). Symptoms of hyponatremia include headache, difficulty concentrating and remembering, and muscle spasms.
  • difficulty controlling your body temperature. Olanzapine may make it more difficult to cool down during exercise or when you are in hot places. Call your if you are feeling more thirsty, are sweating excessively or not at all, or if you are unable to produce urine.

Symbyax can cause drowsiness, dizziness, or blurred vision. Do not drive or operate heavy machinery until you know how Symbyax affects you.

Do not take Symbyax if you:

  • are allergic to Symbyax or any of its ingredients
  • are taking pimozide
  • are taking thioridazine
Food Interactions: 

Grapefruit and grapefruit juice may interact with the olanzapine in this product and lead to potentially dangerous effects. Discuss the use of grapefruit products with your doctor.

Inform MD: 

Before taking Symbyax, tell your doctor about all of your medical conditions. Especially tell your doctor if you:

  • are allergic to Symbyax or any of its ingredients
  • have diabetes, or if anyone in your family has or ever had diabetes
  • have or have had high blood sugar
  • have heart problems
  • have high cholesterol or high triglycerides
  • have had anyone in your family with an irregular heartbeat, or who has died suddenly
  • have ever had a heart attack
  • have ever had a stroke or mini-stroke
  • have ever had seizures
  • have liver problems
  • have glaucoma
  • have dementia
  • have ever been told you have a low number of white blood cells or are prone to getting infections
  • are pregnant or breastfeeding
  • use tobacco products
  • are having surgery, including dental surgery
  • are being treated with electroshock therapy (procedure in which small electric shocks are administered to the brain to treat certain mental illnesses)

Tell your doctor about all the medications you take including prescription and non-prescription medicines, vitamins, and herbal supplements.

Inform MD Image: 

Tell your doctor if you are pregnant or plan to become pregnant.

The FDA categorizes medications based on safety for use during pregnancy. Five categories - A, B, C, D, and X, are used to classify the possible risks to an unborn baby when a medication is taken during pregnancy.

Symbyax falls into category C. In animal studies, pregnant animals were given this medication and had some babies born with problems. No well-controlled studies have been done in humans. Therefore, this medication may be used if the potential benefits to the mother outweigh the potential risks to the unborn child.


Tell your doctor if you are breastfeeding or plan to breastfeed.

Both Symbyax have been detected in human breast milk. Because of the possibility for adverse reactions in nursing infants from Symbyax, a choice should be made whether to stop nursing or to stop use of this medication. The importance of the drug to the mother should be considered.

Drug Usage: 

Take Symbyax exactly as prescribed. It may take a few weeks to notice the effects of this medication.

Do not stop taking Symbyax abruptly. If your doctor needs to lower your dose, he or she will lower your dose gradually.

Symbyax comes in capsule form and is taken once daily.

Take with water in the evening. You should drink plenty of water while you are being treated with Symbyax.

Alcohol may intensify some of the side effects of this medication.

If you miss a dose, take the missed dose as soon as you remember. If it is almost time for the next dose, skip the missed dose and take your next dose at the regular time. Do not take two doses of Symbyax at the same time.

Drug Dosage: 

Take this medication exactly as prescribed by your doctor. Follow the directions on your prescription label carefully.

The dose your doctor recommends may be based on the following:

  • the condition being treated
  • other medical conditions you have
  • other medications you are taking
  • how you respond to this medication
  • your weight
  • your age
  • your gender

The typical recommended starting dose of Symbyax is 6mg olanzapine/20mg fluoxetine (as one capsule). Your doctor may increase your dose gradually up to 12mg olanzapine/50mg fluoxetine if needed.

Your doctor may gradually increase your dose until an effect is seen. Your doctor may also decrease your dosage gradually if needed if you experience unwanted side effects.


If you take too much Symbyax, call your healthcare provider or local Poison Control Center, or seek emergency medical attention right away.

If Symbyax is administered by a healthcare professional in a medical setting, it is unlikely that an overdose will occur. However, if overdose is suspected, seek emergency medical attention.

Other Requirements: 
  • Store Symbyax at room temperature.
  • Keep this and all medicine out of the reach of children.
  • Keep away from moisture. Do not store in the bathroom or other areas where the medication may be exposed to moisture.
  • Keep all appointments with your doctor and the laboratory. Your doctor will order certain lab tests to check your body's response to Symbyax.