What is the most important information I should know about mirtazapine?
Some young people have thoughts about suicide when first taking an antidepressant. Stay alert to changes in your mood or symptoms. Report any new or worsening symptoms to your doctor.
What is mirtazapine?
Mirtazapine is an antidepressant that is used to treat major depressive disorder in adults.
Mirtazapine may also be used for purposes not listed in this medication guide.
What should I discuss with my healthcare provider before taking mirtazapine?
You should not take this medicine if you are allergic to mirtazapine.
Do not use mirtazapine if you have used an MAO inhibitor in the past 14 days. A dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, methylene blue injection, phenelzine, tranylcypromine, and others.
Tell your doctor if you also take stimulant medicine, opioid medicine, herbal products, or medicine for depression, mental illness, Parkinson's disease, migraine headaches, serious infections, or prevention of nausea and vomiting. An interaction with mirtazapine could cause a serious condition called serotonin syndrome.
Tell your doctor if you have ever had:
- low white blood cell counts;
- glaucoma;
- liver or kidney disease;
- low sodium levels in your blood;
- a seizure;
- depression, suicidal thoughts or actions;
- bipolar disorder (manic depression) in you or a family member;
- heart problems or stroke;
- high cholesterol or triglycerides;
- long QT syndrome (in you or a family member); or
- low blood pressure.
Some young people have thoughts about suicide when first taking an antidepressant. Your doctor should check your progress at regular visits. Your family or other caregivers should also be alert to changes in your mood or symptoms.
Tell your doctor if you are pregnant or breastfeeding.
The orally disintegrating tablet may contain phenylalanine and could be harmful if you have phenylketonuria (PKU).
Not approved for use by anyone younger than 18 years old.
How should I take mirtazapine?
Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose. Use the medicine exactly as directed.
Take the medicine at the same time each day, usually at bedtime.
Take the regular tablet form of mirtazapine with water.
You may take mirtazapine with or without food.
Allow the orally disintegrating tablet to dissolve in your mouth without chewing.
Call your doctor if your symptoms do not improve after 4 weeks of treatment.
Do not stop using mirtazapine suddenly, or you could have unpleasant symptoms (such as agitation, confusion, tingling or electric shock feelings). Ask your doctor how to safely stop using this medicine.
Store at room temperature away from moisture, heat, and light.
What happens if I miss a dose?
Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.
What happens if I overdose?
Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.
Overdose symptoms may include confusion, memory problems, drowsiness, and fast heart rate.
What should I avoid while taking mirtazapine?
Drinking alcohol with this medicine can cause side effects.
Avoid driving or hazardous activity until you know how this medicine will affect you. Your reactions could be impaired.
What are the possible side effects of mirtazapine?
Get emergency medical help if you have signs of an allergic reaction (hives, joint pain, fever, difficult breathing, swelling in your face or throat) or a severe skin reaction (fever, sore throat, burning eyes, skin pain, red or purple skin rash with blistering and peeling).
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.
Call your doctor at once if you have:
- racing thoughts, decreased need for sleep, unusual risk-taking behavior, feelings of extreme happiness or sadness, being more talkative than usual;
- blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights;
- a light-headed feeling, like you might pass out;
- severe rash, blisters, or swelling on the palms of your hands or the soles of your feet;
- a seizure;
- low white blood cell counts --fever, chills, sore throat, cough, sores in your mouth or nose, flu-like symptoms, trouble breathing; or
- low sodium level --headache, confusion, slurred speech, severe weakness, vomiting, loss of coordination, feeling unsteady.
Seek medical attention right away if you have symptoms of serotonin syndrome, such as: agitation, hallucinations, fever, sweating, shivering, fast heart rate, muscle stiffness, twitching, loss of coordination, nausea, vomiting, or diarrhea.
Common 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.
What other drugs will affect mirtazapine?
Using mirtazapine with other drugs that make you drowsy can worsen this effect. Ask your doctor before using opioid medication, a sleeping pill, a muscle relaxer, or medicine for anxiety or seizures.
Tell your doctor about all your current medicines. Many drugs can affect mirtazapine, especially:
- cimetidine;
- diazepam;
- St. John's wort;
- tramadol;
- tryptophan (sometimes called L-tryptophan);
- an antibiotic --clarithromycin, rifampin, rifampicin, telithromycin;
- antifungal medicine --itraconazole, ketoconazole;
- antiviral medicine to treat HIV/AIDS --indinavir, nelfinavir, ritonavir, saquinavir;
- medicine to treat mood disorders, thought disorders, or mental illness --such as lithium, other antidepressants, or antipsychotics;
- migraine headache medicine --sumatriptan, rizatriptan, Imitrex, Maxalt, and others; or
- seizure medicine --carbamazepine, phenytoin.
This list is not complete and many other drugs may affect mirtazapine. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.
Where can I get more information?
Your pharmacist can provide more information about mirtazapine.
