What is Mirtazapine?

Mirtazapine is an antidepressant. Mirtazapine affects chemicals in the brain that may become unbalanced and cause depression.
Mirtazapine is used to treat major depressive disorder.
Mirtazapine may also be used for other purposes not listed in this medication guide.

What is the most important information I should know about Mirtazapine?

You may have thoughts about suicide when you first start taking an antidepressant, especially if you are younger than 24 years old. Your doctor will need to check you at regular visits for at least the first 12 weeks of treatment.
Report any new or worsening symptoms to your doctor, such as: mood or behavior changes, anxiety, panic attacks, trouble sleeping, or if you feel impulsive, irritable, agitated, hostile, aggressive, restless, hyperactive (mentally or physically), more depressed, or have thoughts about suicide or hurting yourself.
You should not take this medication if you are allergic to mirtazapine or if you are also taking tryptophan (sometimes called L-tryptophan).
Do not use mirtazapine if you have used an MAO inhibitor within the past 14 days. Serious, life-threatening side effects can occur if you take mirtazapine before the MAO inhibitor has cleared from your body.
Before taking mirtazapine, tell your doctor if you have bipolar disorder, liver or kidney disease, seizures, heart disease, a history of heart attack or stroke, or a history of drug abuse or suicidal thoughts.
It may take up to several weeks before your symptoms improve. Keep using the medication as directed and tell your doctor if your symptoms do not improve after 4 weeks of treatment.
Drinking alcohol can increase certain side effects of mirtazapine.
Mirtazapine may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.

What should I discuss with my healthcare provider before taking Mirtazapine?

You should not take this medication if you are allergic to mirtazapine or if you are also taking tryptophan (sometimes called L-tryptophan).
Do not use mirtazapine if you have taken an MAO inhibitor such as furazolidone (Furoxone), isocarboxazid (Marplan), phenelzine (Nardil), rasagiline (Azilect), selegiline (Eldepryl, Emsam), or tranylcypromine (Parnate) in the last 14 days. Serious, life threatening side effects can occur if you use mirtazapine before the MAO inhibitor has cleared from your body.
If you have any of these other conditions, you may need a mirtazapine dose adjustment or special tests:

• liver or kidney disease
• bipolar disorder (manic depression)
• seizures or epilepsy
• low blood pressure or dizzy spells
• high cholesterol or triglycerides

• heart disease, including angina (chest pain)
• a history of heart attack or stroke; or
• a history of drug abuse or suicidal thoughts

You may have thoughts about suicide while taking an antidepressant, especially if you are younger than 24 years old. Tell your doctor if you have worsening depression or suicidal thoughts during the first several weeks of treatment, or whenever your dose is changed.
Your family or other caregivers should also be alert to changes in your mood or symptoms. Your doctor will need to check you at regular visits for at least the first 12 weeks of treatment.
FDA pregnancy category C. It is not known whether mirtazapine will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using this medication.
It is not known whether mirtazapine passes into breast milk or if it could harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.
The orally disintegrating tablet may contain phenylalanine. Talk to your doctor before using this form of mirtazapine if you have phenylketonuria (PKU).

Mirtazapine Side Effects

What are the possible side effects of Mirtazapine?

Get emergency medical help if you have any of these signs of an allergic reaction: skin rash or hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Call your doctor at once if you have any new or worsening symptoms such as: mood or behavior changes, anxiety, panic attacks, trouble sleeping, or if you feel impulsive, irritable, agitated, hostile, aggressive, restless, hyperactive (mentally or physically), more depressed, or have thoughts about suicide or hurting yourself.
Call your doctor at once if you have a serious side effect such as:

• agitation, hallucinations, fever, fast heart rate, overactive reflexes, nausea, vomiting, diarrhea, loss of coordination, fainting
• fever, chills, body aches, flu symptoms
• white patches or sores inside your mouth or on your lips; or
• headache, trouble concentrating, memory problems, weakness, feeling unsteady, or confusion

Less serious side effects include:

• drowsiness, dizziness
• increased appetite; or
• weight gain

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Mirtazapine Interactions

What other drugs affect Mirtazapine?

Cold or allergy medicine, sedatives, narcotic pain medicine, sleeping pills, muscle relaxers, and medicine for seizures or anxiety can add to sleepiness caused by mirtazapine. Tell your doctor if you regularly use any of these medicines
Many drugs can interact with mirtazapine. Below is just a partial list. Tell your doctor if you are using: