- Haldol (haloperidol) vs. Zyprexa (olanzapine): What's the difference?
- What is haloperidol? What is olanzapine?
- What are the side effects of haloperidol and olanzapine?
- What is the dosage for haloperidol vs. olanzapine?
- What drugs interact with haloperidol and olanzapine?
- Are haloperidol and olanzapine safe to use while pregnant or breastfeeding?
Haldol (haloperidol) vs. Zyprexa (olanzapine): What's the difference?
- Haloperidol and olanzapine are different types of antipsychotic medications used to treat schizophrenia
- Haloperidol is also used to treat acute psychosis and for tics and vocal utterances of Tourette's syndrome.
- Olanzapine is also used to treat acute manic episodes associated with bipolar I disorder and some types of depression.
- A brand name for haloperidol is Haldol.
- Brand names for olanzapine include Zyprexa, Zyprexa Zydis, and Zyprexa Relprevv.
- Side effects of haloperidol and olanzapine that are similar include extrapyramidal effects (sudden, often jerky, involuntary motions of the head, neck, arms, body, or eyes; muscle stiffness, restlessness, Parkinsonism), dizziness, tiredness/drowsiness, weight gain, insomnia, dry mouth, constipation, and dizziness on standing.
- Side effects of haloperidol that are different from olanzapine include hyperactivity, nausea, sedation, erectile dysfunction, menstrual irregularities, swelling of breast tissue in males (gynecomastia), and vomiting.
- Side effects of olanzapine that are different from haloperidol include an inability to sit still (akathisia) and tremor.
- Do not stop using haloperidol suddenly, or you could have unpleasant withdrawal symptoms.
What is haloperidol? What is olanzapine?
Haloperidol is an antipsychotic medication used for treating schizophrenia, acute psychosis, and to control tics and vocal utterances of Tourette's syndrome. Haloperidol interferes with the effects of neurotransmitters in the brain. Haloperidol blocks receptors for the neurotransmitters dopamine and serotonin type 2 so the nerves are not "activated" by these neurotransmitters.
Olanzapine is an atypical antipsychotic used to treat schizophrenia, acute manic episodes associated with bipolar I disorder, and some types of depression. The exact mechanism of action of olanzapine is unknown. It may work by blocking receptors for several neurotransmitters in the brain. It binds to alpha-1, dopamine, histamine H-1, muscarinic, and serotonin type 2 (5-HT2) receptors.

SLIDESHOW
17 Everyday Ways to Ease Depression See SlideshowWhat are the side effects of haloperidol and olanzapine?
Haloperidol
The most common side effects associated with Haldol are:
- extrapyramidal effects (sudden, often jerky, involuntary motions of the head, neck, arms, body, or eyes, muscle stiffness, akathisia, Parkinsonism),
- dizziness,
- hyperactivity,
- tiredness, and
- nausea.
Other important side effects are:
- sedation,
- weight gain,
- erectile dysfunction,
- menstrual irregularities,
- insomnia,
- gynecomastia,
- dry mouth,
- vomiting, and
- constipation
Haldol may cause a condition called "orthostatic hypotension" during the early phase of treatment (first week or two). Orthostatic hypotension causes patients to become dizzy upon arising from a lying or sitting position because of a drop in blood pressure.
Haldol also may cause abnormal heart beats, sudden death, seizures, decreases in red and white blood cells, and withdrawal symptoms.
Elderly patients with dementia-related psychosis and treated with antipsychotic drugs such as Haldol are at an increased risk of early death.
Olanzapine
WARNING
- Elderly patients with dementia related psychosis treated with antipsychotics are at an increased risk of death.
- When using olanzapine and fluoxetine in combination, also refer to the boxed warning section of the package insert for Symbyax.
Common side effects
Common side effects seen with olanzapine are:
- an inability to sit still (akathisia),
- constipation,
- dizziness,
- drowsiness,
- insomnia,
- dry mouth,
- orthostatic hypotension,
- tremor, and
- weight gain.
Several disorders of movement also may occur with olanzapine, for example, extrapyramidal effects (sudden, often jerky, involuntary motions of the head, neck, arms, body, or eyes). Tardive dyskinesia (involuntary movements of the mouth, tongue, jaw, or eyelids) also may occur in 1 in 100 patients receiving olanzapine. Some cases can be irreversible. The likelihood of developing tardive dyskinesia increases with prolonged treatment.
There may be an increased risk of elevated blood sugar levels and diabetes with olanzapine as well as the other antipsychotic medications in its class. Patients should be tested during treatment for elevated blood sugar. Additionally, persons with risk factors for diabetes, including obesity or a family history of diabetes, should have their fasting levels of blood sugar tested before starting treatment and periodically throughout treatment to detect the onset of diabetes. Any patient developing symptoms that suggest diabetes during treatment should be tested for diabetes.
Patients may develop severe sedation, coma, and or delirium after an injection of extended release olanzapine. Patients must be examined for 3 hours after receiving an injection.
Olanzapine may increase prolactin levels. Increased prolactin levels may manifest as abnormal menstruation, sexual dysfunction, and breast enlargement.
What is the dosage for haloperidol vs. olanzapine?
Haloperidol
- The recommended oral dose for schizophrenia is 0.5-5 mg two or three times daily up to a maximum dose of 30 mg daily. The lactate solution dose is 2-5 mg every 4-8 hours as needed by intramuscular injection. The lactate solution may also be administered by intravenous injection at 1-2 mg every 2-4 hours and titrated to effect. The maximum single injection dose is 50 mg and the maximum daily dose is 500 mg daily. The dose for the decanoate solution is 10-20 times the daily oral dose once monthly by intramuscular injection. The decanoate solution should not be administered intravenously.
- The recommended dose for treating Tourette's syndrome is 0.5-5 mg orally two or three times daily.
Olanzapine
- The usual oral dose of olanzapine for treating schizophrenia is 10-20 mg once daily. Therapy is initiated with 5-10 mg/day, and the dose may be increased by 5 mg a day at weekly intervals. The maximum dose is 20 mg daily. The recommended dose of extended release injection is 150-405 mg every 2 or 4 weeks.
- Treatment of bipolar disorder usually is initiated with oral doses of 10-15 mg once daily. The dose may be increased by 5 mg daily at 24 hour intervals. The maximum dose is 20 mg daily.
- The usual dose for treating agitation due to schizophrenia or bipolar disorder is 10 mg administered by intramuscular injection (immediate release). Additional 10 mg doses may be administered, but the efficacy of total doses greater than 30 mg daily have not been adequately evaluated.
- The recommended treatment for resistant depression is 5-20 mg of olanzapine combined with 20-50 mg of fluoxetine once daily in the evening while the recommended treatment for depression associated with bipolar disorder is 5-12.5 mg olanzapine combined with 20-50 mg fluoxetine once daily in the evening.

QUESTION
Laughter feels good because… See AnswerWhat drugs interact with haloperidol and olanzapine?
Haloperidol
Haldol causes sedation, and sedation may be greater if Haldol is taken with alcohol and other drugs that can cause sedation such as the benzodiazepine class of anti-anxiety drugs for example:
The narcotic class of pain medications and its derivatives for example:
- oxycodone and acetaminophen (Percocet)
- hydrocodone/acetaminophen (Vicodin)
- Dilaudid
- Codeine,
- propoxyphene (Darvon)
The tricyclic class of antidepressants for example:
Some antihistamines for example:
- hydroxyzine (Atarax, Vistaril)
- diphenhydramine (Benadryl)
- Tavist
Certain antihypertensive medications for example:
Carbamazepine (Tegretol) may increase the elimination of Haldol, rendering the Haldol less effective. Rifampin (Rifadin) may decrease the elimination of Haldol, increasing the risk of side effects from Haldol.
Olanzapine
- Carbamazepine (Tegretol) can reduce blood concentrations of olanzapine, possibly necessitating higher doses of olanzapine. Other drugs that may also reduce blood levels of olanzapine are omeprazole (Prilosec) and rifampin.
- Smoking may reduce blood concentrations of olanzapine.
- Ciprofloxacin (Cipro), diltiazem (Cardizem, Dilacor, Tiazac), erythromycin, and fluvoxamine (Luvox) may have the opposite effect, that is, they may increase blood levels of olanzapine, and the dose of olanzapine may need to be reduced.
- Olanzapine can cause orthostatic hypotension, a drop in blood pressure upon standing up that may cause dizziness or even fainting. Taking olanzapine with either diazepam (Valium), other related benzodiazepines or alcohol can exaggerate the orthostatic hypotension caused by olanzapine.
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Are haloperidol and olanzapine safe to use while pregnant or breastfeeding?
Haloperidol
- Neonates exposed to antipsychotics during the 3rd trimester of pregnancy may develop withdrawal symptoms and extrapyramidal symptoms.
- Haldol is secreted into breast milk. It should not be used while breast feeding.
Olanzapine
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Summary
Haldol (haloperidol) and Zyprexa (olanzapine) are different types of antipsychotic medications used to treat schizophrenia. Haloperidol is also used to treat acute psychosis and for tics and vocal utterances of Tourette's syndrome. Olanzapine is also used to treat acute manic episodes associated with bipolar I disorder and some types of depression.
Multimedia: Slideshows, Images & Quizzes
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What's Schizophrenia? Symptoms, Types, Causes, Treatment
What is the definition of schizophrenia? What is paranoid schizophrenia? Read about schizophrenia types and learn about...
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Schizophrenia Quiz: What is Schizophrenia?
Schizophrenia is a complex psychiatric disorder. Learn more about the challenges of mental illness with the Schizophrenia Quiz.
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Schizophrenia
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Schizophrenia
Schizophrenia is a disabling brain disorder that may cause hallucinations and delusions and affect a person's ability to communicate and pay attention. Symptoms of psychosis appear in men in their late teens and early 20s and in women in their mid-20s to early 30s. With treatment involving the use of antipsychotic medications and psychosocial treatment, schizophrenia patients can lead rewarding and meaningful lives.
-
Bipolar Disorder vs. Schizophrenia
Bipolar disorder and schizophrenia are mental illnesses that share some risk factors and treatments. Symptoms of bipolar disorder include mood changes and manic and depressive episodes. Symptoms of schizophrenia include unusual behavior, delusions, and hallucinations. Check out the center below for more medical references on mental illnesses, including multimedia (slideshows, images, and quizzes), related disease conditions, treatment and diagnosis, medications, and prevention or wellness.
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Schizoaffective Disorder
Schizoaffective disorder is a mental illness that features schizophrenia and a mood disorder, either major depression or bipolar disorder. Symptoms include agitation, suicidal thoughts, little need for sleep, delusions, hallucinations, and poor motivation. Treatment may involve psychotherapy, medication, skills training, or hospitalization.
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What Is Schizotypal Personality Disorder?
Schizotypal personality disorder is characterized by odd behaviors, feelings, perceptions, and ways of relating to others that interfere with one's ability to function. Medication and psychotherapy can help the sufferer to manage their symptoms.
Treatment & Diagnosis
- Schizophrenia FAQs
- Schizophrenia Predicted by a Gene Variant
- Can a Person Live a Normal Life with Schizophrenia?
- Can a Person Die from Schizophrenia?
- How Does Schizophrenia Start?
- Can You Prevent Schizophrenia?
- Who Is at Risk Developing Schizophrenia?
- What Is the Chemical Imbalance that Causes Schizophrenia?
- Is Schizophrenia a Genetic Disorder?
- What Is a Schizophrenic Person?
Medications & Supplements
- olanzapine disintegrating tablet - oral, Zyprexa
- olanzapine - oral, Zyprexa
- haloperidol - oral, Haldol
- olanzapine - intramuscular, Zyprexa
- olanzapine/fluoxetine - oral, Symbyax
- haloperidol - injection, Haldol
- haloperidol (Haldol)
- Types of Autism Medications and Treatments
- olanzapine (Zyprexa, Zydis)
- Symbyax (olanzapine and fluoxetine hydrochloride)
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Top Haldol haloperidol vs Zyprexa olanzapine Related Articles
Bipolar Disorder vs. Schizophrenia
Bipolar disorder and schizophrenia are mental illnesses that share some risk factors and treatments. Symptoms of bipolar disorder include mood changes and manic and depressive episodes. Symptoms of schizophrenia include unusual behavior, delusions, and hallucinations.haloperidol (Haldol)
Haloperidol (Haldol) is a drug prescribed for the treatment of schizophrenia, acute psychosis, and Tourette's syndrome. Side effects include
- nausea,
- tiredness,
- hyperactivity,
- weight gain,
- insomnia,
- dry mouth,
- vomiting, and
- constipation.
Drug interactions, dosing, and pregnancy and breastfeeding safety information should be reviewed prior to taking this medication.
olanzapine (Zyprexa, Zydis)
Olanzapine (Zyprexa, Zydis, Zyprexa Relprevv) is a drug prescribed for the treatment of schizophrenia associated with bipolar disorder and some types of depression. Side effects, drug interactions, warnings and precautions, and patient safety information should be reviewed prior to taking any medication.Schizoaffective Disorder
Schizoaffective disorder is a mental illness that features schizophrenia and a mood disorder, either major depression or bipolar disorder. Symptoms include agitation, suicidal thoughts, little need for sleep, delusions, hallucinations, and poor motivation. Treatment may involve psychotherapy, medication, skills training, or hospitalization.Schizophrenia
Schizophrenia is a disabling brain disorder that may cause hallucinations and delusions and affect a person's ability to communicate and pay attention. Symptoms of psychosis appear in men in their late teens and early 20s and in women in their mid-20s to early 30s. With treatment involving the use of antipsychotic medications and psychosocial treatment, schizophrenia patients can lead rewarding and meaningful lives.What's Schizophrenia? Symptoms, Types, Causes, Treatment
What is the definition of schizophrenia? What is paranoid schizophrenia? Read about schizophrenia types and learn about schizophrenia symptoms, signs, and treatment options.Schizophrenia Quiz
Schizophrenia is a complex psychiatric disorder. Learn more about the challenges of mental illness with the Schizophrenia Quiz.What Is Schizotypal Personality Disorder?
Schizotypal personality disorder is characterized by odd behaviors, feelings, perceptions, and ways of relating to others that interfere with one's ability to function. Medication and psychotherapy can help the sufferer to manage their symptoms.Symbyax (olanzapine and fluoxetine hydrochloride)
Symbyax is a prescription medicine used for short-term treatment of episodes of depression that happen with Bipolar I Disorder in people age 10 or older and treatment of episodes of depression that do not respond to 2 other medicines, also called treatment-resistant depression, in adults. Serious side effects of Symbyax include increased risk of suicidal thoughts and behaviors and dementia-related psychosis, and others.