Free Nutritional Health Information and Tools

Mirtazapine (Systemic)

Home PageTable Of ContentsPrevious PageNext Page

Mirtazapine (Systemic)

US Brand Names

• Remeron

• Remeron SolTab


Mirtazapine (mir-TAZ-a-peen) is used to treat mental depression.

This medicine is available only with your doctor's prescription, in the following dosage form(s):


    • Oral Disintegrating Tablets (U.S.)

    • Tablets (U.S.)

Special Considerations

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For mirtazapine, the following should be considered:


Tell your doctor if you have ever had any unusual or allergic reaction to mirtazapine. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.


Mirtazapine has not been studied in pregnant women. However, this medicine has been shown to cause death of the fetus in animals given doses many times higher than the usual human dose. Mirtazapine has not been shown to cause birth defects in animals.


It is not known whether mirtazapine passes into breast milk. Although most medicines pass into breast milk in small amounts, many of them may be used safely while breast-feeding. Mothers who are taking this medicine and who wish to breast-feed should discuss this with their doctor.


Studies on this medicine have been done only in adult patients, and there is no specific information comparing use of mirtazapine in children with use in other age groups.

Mirtazapine must be used with caution in children with depression. Studies have shown occurrences of children thinking about suicide or attempting suicide in clinical trials for this medicine. More study is needed to be sure mirtazapine is safe and effective in children.

Older adults

This medicine has been tested and has not been shown to cause different side effects or problems in older people than it does in younger adults. However, it is removed from the body more slowly in older people.

Other medicines

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking mirtazapine, it is especially important that your health care professional know if you are taking any of the following:

    • Alcohol or

    • Central nervous system (CNS) depressants (medicines that cause drowsiness) or

    • Tricyclic antidepressants (amitriptyline [e.g., Elavil], amoxapine [e.g., Asendin], clomipramine [e.g., Anafranil], desipramine [e.g., Pertofrane], doxepin [e.g., Sinequan], imipramine [e.g., Tofranil], nortriptyline [e.g., Aventyl], protriptyline [e.g., Vivactil], trimipramine [e.g., Surmontil])-Using these medicines with mirtazapine may increase the CNS depressant effects

    • Monoamine oxidase (MAO) inhibitor activity (isocarboxazid [e.g., Marplan], phenelzine [e.g., Nardil], procarbazine [e.g., Matulane], selegiline [e.g., Eldepryl], tranylcypromine [e.g., Parnate]) Do not take mirtazapine while you are taking, or within 2 weeks of taking, an MAO inhibitor or you may develop confusion, agitation, restlessness, stomach or intestinal symptoms, sudden high body temperature, extremely high blood pressure, and severe convulsions; at least 14 days should be allowed between stopping treatment with one medicine and starting treatment with the other

Other medical problems

The presence of other medical problems may affect the use of mirtazapine. Make sure you tell your doctor if you have any other medical problems, especially:

    • Convulsions (seizures) (history of)-Mirtazapine has been reported to cause seizures rarely

    • Dehydration or

    • Heart disease or

    • Stroke (history of)-Mirtazapine may make the condition worse by causing low blood pressure (hypotension)

    • Kidney disease-Effects of mirtazapine may be increased because of slower removal from the body

    • Liver disease-Mirtazapine may cause liver problems; also, effects of mirtazapine may be increased because of slower removal from the body

    • Mania (a type of mental illness) (or history of)-Mirtazapine may cause this problem to recur

    • Phenylketonuria (PKU)-The oral disintegrating tablets may contain aspartame, which can make your condition worse


Take this medicine only as directed by your doctor in order to improve your condition as much as possible. Do not take more of it and do not take it more often than your doctor ordered.

Mirtazapine may be taken with or without food, on a full or empty stomach. If your doctor tells you to take it a certain way, follow your doctor's instructions.

For patients using the oral disintegrating tablet form of this medicine:

    • Make sure your hands are dry.

    • Do not push the tablet through the foil backing of the package. Instead, gently peel back the foil backing and remove the tablet.

    • Immediately place the tablet on top of the tongue.

    • The tablet will dissolve in seconds, and you may swallow it with your saliva. You do not need to drink water or other liquid to swallow the tablet.


The dose of mirtazapine will be different for different patients. Follow your doctor's orders or the directions on the label . The following information includes only the average doses of mirtazapine. If your dose is different, do not change it unless your doctor tells you to do so.

The number of tablets that you take depends on the strength of the medicine.

    • For oral dosage form (tablets and oral disintegrating tablets):

      o For mental depression:

        Adults-At first, 15 milligrams (mg) once a day, preferably in the evening just before you go to sleep. Your doctor may increase the dose if necessary. However, the dose usually is not more than 45 mg a day.

        Children-Use and dose must be determined by your doctor.

Missed dose

If you miss a dose of this medicine, take it as soon as possible if you remember it the same day. However, if you don't remember until the next day, skip the missed dose and return to your regular dosing schedule. Do not double doses.


To store this medicine:

    • Keep out of the reach of children.

    • Store away from heat and direct light.

    • Do not store in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down.

    • Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.


It is important that your doctor check your progress at regular visits, to allow for changes in your dose and to help reduce any side effects.

Do not take mirtazapine with monoamine oxidase (MAO) inhibitors (e.g., furazolidone, phenelzine, procarbazine, selegiline, or tranylcypromine) or sooner than 14 days after stopping an MAO inhibitor. Do not take an MAO inhibitor sooner than 14 days after stopping mirtazapine. To do so may increase the chance of serious side effects.

This medicine may add to the effects of alcohol and other CNS depressants (medicines that make you drowsy or less alert). Some examples of CNS depressants are antihistamines or medicine for hay fever, other allergies, or colds; sedatives, tranquilizers, or sleeping medicine; prescription pain medicine or narcotics; barbiturates; medicine for seizures; muscle relaxants; or anesthetics, including some dental anesthetics. Check with your doctor before taking any of the above while you are taking this medicine.

Check with your doctor immediately if you develop fever, chills, sore throat, or sores in the mouth . These may be signs of a very serious blood problem that has occurred rarely in patients taking mirtazapine.

Mirtazapine may cause drowsiness or trouble in thinking. Make sure you know how you react to this medicine before you drive, use machines, or do other jobs that require you to be alert and clearheaded.

Dizziness, light-headedness, or fainting may occur , especially when you get up from a lying or sitting position. Getting up slowly may help. If this problem continues or gets worse, check with your doctor.

This medicine may cause dryness of the mouth. For temporary relief, use sugarless gum or candy, melt bits of ice in your mouth, or use a saliva substitute. However, if your mouth feels dry for more than 2 weeks, check with your medical doctor or dentist. Continuing dryness of the mouth may increase the chance of dental disease, including tooth decay, gum disease, and fungus infections.

Side Effects

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:


Convulsions (seizures); mouth sores; sore throat, chills, or fever.

Also, check with your doctor as soon as possible if any of the following side effects occur:

Less common

Decreased or increased movement; mood or mental changes, including abnormal thinking, agitation, anxiety, confusion, and feelings of not caring; shortness of breath; skin rash; swelling.


Decreased sexual ability; menstrual pain; missing periods; mood or mental changes, including anger, feelings of being outside the body, hallucinations (seeing, hearing, or feeling things that are not there), mood swings, and unusual excitement.

Other 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. However, check with your doctor if any of the following side effects continue or are bothersome:

More common

Constipation; dizziness; drowsiness; dryness of mouth; increased appetite; weight gain.

Less common

Abdominal pain; abnormal dreams; back pain; dizziness or fainting when getting up suddenly from a lying or sitting position; increased need to urinate; increased sensitivity to touch; increased thirst; low blood pressure; muscle pain; nausea; sense of constant movement of self or surroundings; trembling or shaking; vomiting; weakness.

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.

December 18, 2003

Top Of PageHome PageTable Of ContentsPrevious PageNext Page