What To Know About Methoprazine (Nozinan)

Treats some mental and mood disorders

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Methoprazine (brand name Nozinan), also known as levomepromazine, is commonly used to treat mental and mood disorders, including schizophrenia, manic depression, and other psychotic disorders. It also helps with anxiety and tension, pain, and nausea and vomiting caused by certain conditions. Methoprazine can also be used as a sedative. It is not approved for use or available in the U.S., but it may be available in certain other countries.

It belongs to a group of phenothiazine drugs. The medication blocks dopamine receptors to help lessen overactivity of dopamine in the brain, which is often found in people with schizophrenia.

Methoprazine is available under a wide variety of brand names, most commonly, Nozinan. Others include Neurocil and Levoprome.

Unrecognizable Woman Pours Pills into Hand from Prescription Bottle

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Methoprazine is approved for use in the treatment of mood disorders such as schizophrenia and bipolar disorder. It can also be used in the management of symptoms associated with terminal illnesses such as pain, distress, nausea, and vomiting.

Psychotic Disorders

In the case of its use in the treatment of schizophrenia, the medication works by blocking the effects of dopamine as well as other neurotransmitters, restoring them to healthier levels. This then leads to a reduction in unwanted symptoms that are associated with this particular mental disorder, including hallucinations, agitation, disturbed thoughts, and delusions.


Methoprazine has been used to help treat various conditions that can lead to heightened anxiety and tension.  


This medication can be used to help treat chronic pain in those with conditions such as cancer or neuralgia (pain caused by nerve damage or irritation). Pain associated with phantom limb syndrome is also treated using methoprazine.


Though not the first choice for use as an anesthetic, the use of methoprazine can be used as a pre- and post-op sedative.

Nausea and Vomiting

When used in the treatment of nausea and vomiting, methoprazine works by hindering the receptors in the vomiting center from receiving messages from the chemoreceptor trigger zone. This stops the receipt of messages that would signal the body to feel sick and throw up. It is generally used to treat nausea and vomiting in terminally ill patients who have not had any luck with other antiemetic medications.  

Before Taking

Prior to starting any new medication, it’s important that you speak to your healthcare provider to determine if the drug is right for you and your condition. Your practitioner will conduct a series of exams to determine if your condition could benefit from methoprazine. These consultations will vary depending on the specific illness you have.

For those with mood disorders, an assessment of symptoms, medical and medication history will need to be performed. In other conditions, such as chronic pain or anxiety and tension, methoprazine is generally used as a second-line treatment following the failure of other medical therapies.

Other tests that may be needed to determine whether methoprazine is the right fit include an ECG to rule out any heart issues that could be exacerbated by the use of this medication. If treatment is long-term, liver function tests may need to be performed.

Some drugs may pose only minor interaction risks, while others may decrease the efficacy of the drug, and others increase the risk of serious side effects. A thorough discussion with your healthcare provider will help them decide if methoprazine is the right treatment for your condition.

Precautions and Contraindications

Methoprazine is not right for everybody. Select groups of people should not take this drug at all, or should do so under very careful observation of their healthcare provider. This includes older adults with dementia because research has shown that antipsychotics can increase the risk of stroke in this demographic.

This also includes people with a higher risk of blood clots. Family or personal history of blood clots or other risk factors, including being on the birth control pill, smoking, being overweight, over the age of 40, recent surgery, or immobility can all put someone at higher risk of developing blood clots. Those with epilepsy, seizure disorders, or those at risk of epilepsy due to brain damage or alcohol withdrawal should use methoprazine with caution because it can potentially aggravate these conditions.

Who Should Not Take Methoprazine?

This medication should not be used or prescribed to:

  • Anyone who is allergic to methoprazine or any of its ingredients or those with an allergy to other phenothiazines, including prochlorperazine or trifluoperazine

Risks and benefits of taking this medication should be carefully assessed in:

  • Pregnant women
  • Those with central nervous system depression
  • Coma patients
  • People with blood dyscrasias

People with any of the following health conditions or histories will need close monitoring while using methoprazine because they are at higher risk of side effects:

  • Decreased kidney or liver function, low fluid volume in the body due to kidney dialysis or diuretic therapy
  • A history of cardiac disease, including heart failure or arrhythmias
  • Diabetes because this methoprazine may increase blood sugar levels within the body
  • Parkinson’s disease
  • Nutritional deficiencies such as potassium, magnesium, or calcium since this medication can increase heart irregularities in people with nutritional deficiencies
  • A closed-angle glaucoma history
  • Dehydration and malnutrition
  • Excessive sedation caused by alcohol, sleeping pills, or other narcotics
  • A tumor in the adrenal glands
  • Abnormal muscle weakness
  • An enlarged prostate gland

Other Drug Class Names

There are other phenothiazine medications that can be used to treat the same disorders, including:

  • Chlorpromazine (Thorazine)
  • Mesoridazine (Serentil)
  • Perphenazine (Etrafon and Trilafon)
  • Procholoperazine (Compazine)
  • Thioridazine (Mellaril)
  • Trifjuoperazine (Stelazine)


The oral tablets of methoprazine come in 2 milligrams (mg), 5 mg, 25 mg, and 50 mg, and the dosage will depend on each person’s individual health condition and history. All listed dosages are according to the drug manufacturer.

Adults using methoprazine as a tranquilizer, anxiolytic (for reducing anxiety), or analgesic will begin treatment with a low dose of 6 to 25 mg per day. The dosage will increase until the desired effects are achieved. If used as a sedative or for sleep problems, a dosage of 10 to 25 mg at night time is usually prescribed.

If a person with psychosis is taking this medication, the dosage will begin at higher levels. Treatment will start at 50 to 75 mg per day. In some cases, dosages may reach up to 1 gram per day, depending on the condition and response to treatment.

Some people may need to start at heavier doses, and if that is the case, treatment will likely start with 100 to 200 mg spread out over the course of a day with bed rest for the first few days to monitor response to the medication.


Children can take methoprazine for certain conditions, but their dosages will vary depending on weight. The initial dose should be ¼ of a milligram per kilogram (kg) of body weight. The dosing for children can increase gradually over time, but should never exceed 40 mg per day if the child is under 12 years old.

Doses of this medication will need to be adjusted accordingly for both children and adults to ensure its efficacy. In the event that you miss a dose, do not take a double dose next time. You will need to contact your healthcare provider to establish a new dosing schedule since this medication and its effects rely heavily on a proper dosing routine.

How To Take and Store

The timing to take methoprazine will vary from person to person, but it is generally advised that the medication be taken with meals two to three times per day. It’s important to check with your pharmacist to ensure you’re on the right dosing schedule as discussed with your healthcare provider.

This medication should be stored in a cool and dry place and out of direct sunlight. Since this medication can be dangerous for those the medication is not prescribed for, it should be kept out of reach. If disposing of any tablets, it’s important to do so at the pharmacy. This medication should never be flushed down the toilet or thrown in the garbage.  

Side Effects

Methoprazine can cause a variety of side effects. Depending on the person, their health history, and their response to the medication, those side effects will range in severity and length. Side effects have been reported in at least 1% of people who have taken methoprazine.


Common side effects are those that appear more regularly and are mild in nature. They tend to dissipate as the body adjusts to the new medication. Some common side effects of methoprazine include:

  • Sleepiness
  • Weakness
  • Dry mouth
  • A drop in blood pressure when going from lying down to a sitting or standing position, which could result in dizziness or feelings of being lightheaded
  • Constipation (can become serious)
  • Skin rashes
  • Photosensitivity
  • Difficulty urinating
  • Weight gain

These side effects may not happen to everyone. However, if you experience them and they continue to worsen, contact your healthcare provider for help.


More severe side effects may occur. If you experience any of the following symptoms, you should seek prompt medical attention. These side effects include:

  • Muscle spasms or stiffness
  • Tremors
  • Restlessness
  • Mask-like facial expression
  • Drooling
  • Abnormal movements of the extremities
  • Disturbances in the body’s ability to regulate temperature (more common in older adults)
  • Decreased number of blood cells
  • Jaundice (yellowing of the eyes or skin)
  • Arrhythmias
  • Easy bleeding and bruising
  • Fever
  • Persistent sore throat
  • Persistent nausea, vomiting, and loss of appetite
  • Abdominal pain
  • Sudden pain, swelling, or redness
  • Severe dizziness accompanied by fainting spells
  • Seizures
  • Symptoms of an allergic reaction (such as a rash, itching, swelling of the face, tongue, and throat), severe dizziness, and trouble breathing

When to Call a Healthcare Provider

If you experience any of the serious side effects while taking methoprazine, call your healthcare provider or 911 for emergency medical assistance.


The use of methoprazine can lead to certain complications. For people who have diabetes, blood glucose levels should be monitored frequently. This is because methoprazine has been shown to increase blood glucose levels (hyperglycemia). Signs to look out for include unusual hunger or thirst, blurred vision, fatigue, headache, and an increased need to urinate.

In very rare cases, methoprazine may cause a serious condition known as neuroleptic malignant syndrome (NMS). This condition requires emergency medical help. The symptoms to watch out for include:

  • Fever
  • Muscle stiffness, pain, tenderness, and weakness
  • Severe tiredness or confusion
  • Increased sweating
  • Changes in heartbeat, including a quickened or irregular heartbeat
  • Dark-colored urine or a change in the amount of passed urine

Methoprazine Side Effects Affect Men and Women in Different Ways

The use of methoprazine may also result in the loss of bone mineral density, and rare cases of priapism (prolonged erection) have been documented in men. It has also been shown to cause an inability to produce sperm and the enlargement of breasts in men.

In women, methoprazine may lead to an overproduction of prolactin, which can cause a surplus in unwanted breast milk, missed or stopped periods, and difficulty becoming pregnant. If you are taking methoprazine and develop these symptoms, contact your healthcare provider right away.

While taking methoprazine, it’s important to know what other drugs could cause potentially harmful interactions within the body. One of the most common drug interactions with methoprazine is levodopa, a potent medication used in the treatment of Parkinson’s disease.


You should tell your healthcare provider about all medications or supplements you are on to ensure there are no harmful interactions. This is especially important if you are using:

  • Opioid pain or cough relievers
  • Recreational drugs, including marijuana and alcohol
  • Sleep or anxiety medications such as lorazepam and zolpidem
  • Muscle relaxants
  • Antihistamines

Any over-the-counter medications that contain ingredients that could cause drowsiness should also be avoided while taking methoprazine. This list is not exhaustive, and there are many other medications that could pose potential risks if an interaction does occur.

It is not advised to stop this medication suddenly. The only exception is an allergic reaction, in which case you should stop immediately taking methoprazine and seek emergency medical assistance.

6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Angelica Bottaro
Angelica Bottaro is a professional freelance writer with over 5 years of experience. She has been educated in both psychology and journalism, and her dual education has given her the research and writing skills needed to deliver sound and engaging content in the health space.