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.
Side Effects Of Mirtazapine
Mirtazapine may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
- increased weight and appetite
- dry mouth
Some side effects can be serious. If you experience any of the following symptoms or those listed in the WARNINGS and 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
Mirtazapine may cause other side effects. Call your doctor if you have any unusual problems while you are taking this medication.
Warnings & Precautions
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 if you are taking a monoamine oxidase (MAO) inhibitor such as isocarboxazid (Marplan), linezolid (Zyvox), methylene blue, phenelzine (Nardil), selegiline (Eldepryl, Emsam, Zelapar), and tranylcypromine (Parnate) or if you have stopped taking an MAO inhibitor within the past 14 days. Your doctor will probably tell you not to take mirtazapine. If you stop taking mirtazapine, you should wait at least 14 days before you start to take an MAO inhibitor.
- tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, and nutritional supplements you are taking or plan to take. Be sure to mention any of the following: anticoagulants (‘blood thinners’) such as warfarin (Coumadin, Jantoven); antidepressants such as amitriptyline (Elavil), amoxapine (Asendin), clomipramine (Anafranil), desipramine (Norpramin), doxepin, imipramine (Tofranil), nortriptyline (Aventyl, Pamelor), protriptyline (Vivactil), and trimipramine (Surmontil); certain antifungals such as ketoconazole (Nizoral); buspirone; carbamazepine (Carbatrol, Epitol, Equetro, Tegretol, other); cimetidine (Tagamet); diazepam (Valium); erythromycin (E.E.S., E-mycin, Erythrocin); fentanyl (Abstral, Actiq, Fentora, Onsolis, others); lithium (Eskalith, Lithobid); medications for migraine headaches such as almotriptan (Axert), eletriptan (Relpax), frovatriptan (Frova), naratriptan (Amerge), rizatriptan (Maxalt), sumatriptan (Imitrex), and zolmitriptan (Zomig); certain medications to treat HIV; medications for anxiety and seizures; nefazodone; phenytoin (Dilantin); rifampin (Rimactane, Rifadin, in Rifater, in Rifamate); sedatives; selective serotonin reuptake inhibitors (SSRIs) such as citalopram (Celexa), escitalopram (Lexapro), fluoxetine (Prozac, Sarafem), fluvoxamine (Luvox), paroxetine (Paxil, Pexeva), and sertraline (Zoloft); selective serotonin and norepinephrine reuptake inhibitors (SNRIs) such as desvenlafaxine (Pristiq), duloxetine (Cymbalta), and venlafaxine (Effexor); sleeping pills; tramadol (Ultram); and tranquilizers. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
- tell your doctor what herbal products you are taking, especially St. John’s wort and tryptophan.
- 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 mental retardation), 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.
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.
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.
It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.
All information has been provided courtesy of MedLinePlus from the National Library of Medicine and from the FDA.