Mirtazapine is the generic equivalent of Remeron®.

By law, a generic drug must be the same as its brand name counterpart in terms of active ingredient, dosage, safety, effectiveness, strength, stability, and quality. A generic may, however, differ in its inactive ingredients (i.e. flavoring, fillers, and preservatives).

Mirtazapine (Remeron®) does come with serious warnings. These include:

• Increased risk of suicidal thoughts or actions in adolescents and young adults*

• Increased risk of infection due to agranulocytosis (decreased white blood cell count)

• Serotonin syndrome—a rare, but potentially life-threatening condition that occurs when there’s too much serotonin in the brain

• Glaucoma

• Prolongation of QT interval—a potentially life-threatening heart rhythm disorder that can cause fast, irregular heartbeats

• Extreme drowsiness, causing impaired judgment, thinking and motor skills

• Manic episodes or hypomania in patients with bipolar disorder

• Elevated cholesterol and triglyceride levels

• Decreased sodium levels

If any of the above concern you, speak with your doctor or pharmacist about your perceived risk and other treatment options that exist.

*This warning is a boxed warning. A boxed warning is the most serious type of medication warning assigned by the FDA.

Mirtazapine is FDA approved for the treatment of:

• Major depressive disorder (MDD) or depression

• Insomnia (off-label)

• Appetite stimulant (off-label)

Mirtazapine is a tetracyclic antidepressant. It works by blocking the brain’s absorption of norepinephrine and serotonin, “feed good” chemicals in your brain. The end result? An increased level of norepinephrine and serotonin in your brain, which is thought to improve mood. The drug also works at other receptors in the brain.

The most common side effects of mirtazapine include:

• Drowsiness

• Increased appetite

• Weight gain

• Dizziness

• Dry mouth

Side effects may improve over time as your body adjusts to the medicine.

This list doesn’t represent all possible side effects (or serious side effects) of mirtazapine. If you’re experiencing any ongoing, bothersome side effect(s), tell your healthcare provider right away.

If you’d like to learn more, speak with your doctor or pharmacist. The Food and Drug Administration (FDA) also has a helpful medication guide for mirtazapine here.

Mirtazapine can interact with some medicines and supplements. It’s always recommended to give both your doctor and pharmacy an updated list of everything you’re taking, so drug interactions can be identified.

Some medicines and supplements mirtazapine can interact with include:

• Seizure drugs: carbamazepine, phenytoin

• Rifampin

• Anti-infection drugs: ketoconazole, clarithromycin

• Cimetidine

• SSRIs (selective serotonin reuptake inhibitors): citalopram, sertraline, fluoxetine, paroxetine

• SNRIs (serotonin and norepinephrine reuptake inhibitors): desvenlafaxine, venlafaxine, duloxetine, milnacipran

• Tricyclic antidepressants: amitriptyline, doxepin, imipramine, nortriptyline

• Opioids: fentanyl, tramadol, morphine, codeine

• St. John’s Wort

This list doesn’t represent all the drugs that may not be safe to take with mirtazapine. If you’re unsure whether a certain drug or supplement can be taken with mirtazapine, speak with your doctor or pharmacist. The FDA also has a helpful medication guide for mirtazapine here.

If you accidentally miss your dose of mirtazapine, take the dose as soon as you remember. If it’s almost time for your next dose (within 2 hours), skip the missed dose and take your next dose at the usual time. Don't take 2 doses at the same time or extra doses.

If you’re taking mirtazapine for sleep, it’s generally recommended to take your pill one hour before bedtime.

Mirtazapine may be taken with or without food.

During pregnancy: Research suggests mirtazapine may be safe in pregnancy, but data is sparse.

While breastfeeding: Mirtazapine passes into breast milk in small amounts and has often been used during breastfeeding without any problems.

It’s important to treat mental health-related conditions when pregnant or nursing, as untreated depression, anxiety, or other mental illnesses can harm both you and baby. Always let your provider know if you’re pregnant or breastfeeding, so you can discuss the risks and benefits of starting or continuing mirtazapine. Always let your provider know if you’re pregnant or breastfeeding, so you can discuss the benefits and risks of starting or continuing mirtazapine.

It’s recommended to avoid or limit the use of alcohol when taking mirtazapine. Alcohol can intensify the side effects of mirtazapine, including extreme drowsiness and dizziness.