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URL of this page: https://medlineplus.gov/druginfo/meds/a697009.html

Mirtazapine

pronounced as (mir taz' a peen)

IMPORTANT WARNING:

IMPORTANT WARNING: has been expanded.

A small number of children, teenagers, and young adults (up to 24 years of age) who took antidepressants ('mood elevators') such as mirtazapine during clinical studies became suicidal (thinking about harming or killing oneself or planning or trying to do so). Children, teenagers, and young adults who take antidepressants to treat depression or other mental illnesses may be more likely to become suicidal than children, teenagers, and young adults who do not take antidepressants to treat these conditions. However, experts are not sure about how great this risk is and how much it should be considered in deciding whether a child or teenager should take an antidepressant. Children younger than 18 years of age should not normally take mirtazapine, but in some cases, a doctor may decide that mirtazapine is the best medication to treat a child's condition.

You should know that your mental health may change in unexpected ways when you take mirtazapine or other antidepressants even if you are an adult over 24 years of age. You may become suicidal, especially at the beginning of your treatment and any time that your dose is increased or decreased. You, your family, or your caregiver should call your doctor right away if you experience any of the following symptoms: new or worsening depression; thinking about harming or killing yourself, or planning or trying to do so; extreme worry; agitation; panic attacks; difficulty falling asleep or staying asleep; aggressive behavior; irritability; acting without thinking; severe restlessness; and frenzied abnormal excitement. Be sure that your family or caregiver knows which symptoms may be serious so they can call the doctor if you are unable to seek treatment on your own.

Your healthcare provider will want to see you often while you are taking mirtazapine, especially at the beginning of your treatment. Be sure to keep all appointments for office visits with your doctor.

The doctor or pharmacist will give you the manufacturer's patient information sheet (Medication Guide) when you begin treatment with mirtazapine. Read the information carefully and ask your doctor or pharmacist if you have any questions. You also can obtain the Medication Guide from the FDA website: https://www.fda.gov/Drugs/DrugSafety/ucm085729.htm.

No matter what your age, before you take an antidepressant, you, your parent, or your caregiver should talk to your doctor about the risks and benefits of treating your condition with an antidepressant or with other treatments. You should also talk about the risks and benefits of not treating your condition. You should know that having depression or another mental illness greatly increases the risk that you will become suicidal. This risk is higher if you or anyone in your family has or has ever had bipolar disorder (mood that changes from depressed to abnormally excited) or mania (frenzied, abnormally excited mood) or has thought about or attempted suicide. Talk to your doctor about your condition, symptoms, and personal and family medical history. You and your doctor will decide what type of treatment is right for you.

Why is this medication prescribed?

Mirtazapine is used to treat depression. Mirtazapine is in a class of medications called antidepressants. It works by increasing certain types of activity in the brain to maintain mental balance.

How should this medicine be used?

Mirtazapine comes as a tablet and as a disintegrating tablet to take by mouth. It usually is taken once a day at bedtime. It may be taken with or without food. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take mirtazapine exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

To take a mirtazapine disintegrating tablet, open the blister pack with dry hands and place the tablet on your tongue. The tablet will disintegrate on the tongue and can be swallowed with saliva. No water is needed to swallow disintegrating tablets. Once the tablet is removed from the blister pack, it cannot be stored. Do not split mirtazapine disintegrating tablets.

It may take several weeks or longer for you to feel the full benefit of mirtazapine. Continue to take mirtazapine even if you feel well. Do not stop taking mirtazapine without talking to your doctor. Your doctor probably will decrease your dose gradually.

Other uses for this medicine

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before taking mirtazapine,

  • tell your doctor and pharmacist if you are allergic to mirtazapine, any other medications, or any of the ingredients in mirtazapine tablets or disintegrating tablets. Ask your doctor or pharmacist for a list of the ingredients.
  • tell your doctor or pharmacist if you are taking the following medications or have stopped taking them within the past two weeks: a monoamine oxidase (MAO) inhibitor such as isocarboxazid (Marplan), linezolid (Zyvox), methylene blue, phenelzine (Nardil), selegiline (Eldepryl, Emsam, Zelapar), and tranylcypromine (Parnate).
  • some medications should not be taken with mirtazapine. Other medications may cause dosing changes or extra monitoring when taken with mirtazapine. Make sure you have discussed any medications you are currently taking or plan to take before starting mirtazapine with your doctor and pharmacist. Before starting, stopping, or changing any medications while taking mirtazapine, please get the advice of your doctor or pharmacist.
  • the following nonprescription or herbal products may interact with mirtazapine: St. John's wort; trytophan; cimetidine (Tagamet). Be sure to let your doctor and pharmacist know that you are taking these medications before you start taking mirtazapine. Do not start any of these medications while taking mirtazapine without discussing with your healthcare provider..
  • tell your doctor if you have or have ever had a heart attack, low blood pressure, heart, kidney, or liver disease, or high cholesterol.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking mirtazapine, call your doctor.
  • if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking mirtazapine.
  • you should know that this medication may make you drowsy. Do not drive a car or operate machinery until you know how this medication affects you.
  • remember that alcohol can add to the drowsiness caused by this medication.
  • if you have phenylketonuria (PKU, an inherited condition in which a special diet must be followed to prevent damage to your brain that can cause severe intellectual disability), you should know that the orally disintegrating tablets contain aspartame that forms phenylalanine.
  • you should know that mirtazapine may cause angle-closure glaucoma (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). Talk to your doctor about having an eye examination before you start taking this medication. 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.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget a dose?

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

What side effects can this medication cause?

Mirtazapine may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • drowsiness
  • dizziness
  • anxiousness
  • confusion
  • increased weight and appetite
  • dry mouth
  • constipation
  • nausea
  • vomiting

Some side effects can be serious. If you experience any of the following symptoms or those listed in the IMPORTANT WARNING or SPECIAL PRECAUTIONS section, call your doctor immediately or get emergency medical treatment:

  • flu-like symptoms, fever, chills, sore throat, mouth sores, or other signs of infection
  • chest pain
  • fast heartbeat
  • seizures

Mirtazapine may cause other side effects. Call your doctor if you have any unusual problems while you are taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (https://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

Keep all medication out of sight and reach of children as many containers are not child-resistant. Always lock safety caps. Place the medication in a safe location – one that is up and away and out of their sight and reach. https://www.upandaway.org

Dispose of unneeded medications in a way so that pets, children, and other people cannot take them. Do not flush this medication down the toilet. Use a medicine take-back program. Talk to your pharmacist about take-back programs in your community. Visit the FDA's Safe Disposal of Medicines website https://goo.gl/c4Rm4p for more information.

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What other information should I know?

Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests to check your response to mirtazapine.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

Keep a written list of all of the prescription and nonprescription (over-the-counter) medicines, vitamins, minerals, and dietary supplements you are taking. Bring this list with you each time you visit a doctor or if you are admitted to the hospital. You should carry the list with you in case of emergencies.

Brand names

  • Remeron®
  • Remeron® SolTab
Last Revised - 01/15/2022