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mirtazapine vs phenelzine

Side-by-side comparison of mirtazapine and phenelzine. Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.

moderate Known Drug Interaction

Examples selegiline, tranylcypromine, isocarboxazid, phenelzine, linezolid, methylene blue Other Serotonergic Drugs Clinical Impact The concomitant use of serotonergic drugs with mirtazapine increases the risk of serotonin syndrome.

Recommendation: Do not take these medicines together. Your doctor will manage the timing of when you start or stop each medication.

Drug Class
mirtazapine Noradrenergic and Specific Serotonergic Antidepressant (NaSSA)
phenelzine Monoamine Oxidase Inhibitor (MAOI)
Type
mirtazapine Prescription
phenelzine Prescription
Summary
mirtazapine

Mirtazapine is a medicine used to treat depression in adults. It can help improve your mood and energy levels.

phenelzine

Phenelzine (Nardil) is a medicine used to treat depression. It belongs to a class of drugs called MAO inhibitors.

What It Treats
mirtazapine

Mirtazapine is used to treat major depressive disorder (MDD) in adults. This condition can cause you to feel sad, lose interest in activities, and have trouble with sleeping or eating. Mirtazapine can help improve these symptoms.

phenelzine

This medicine treats depression, especially when it involves anxiety, phobias, or hypochondria. It is often used when other antidepressants haven't worked. It may not be as effective for severe depression with 'endogenous' features.

How It Works
mirtazapine

Mirtazapine works by affecting certain chemicals in the brain called neurotransmitters. It helps to increase the levels of norepinephrine and serotonin. These chemicals can help improve mood and reduce symptoms of depression.

phenelzine

Phenelzine works by blocking an enzyme called monoamine oxidase (MAO) in your body. MAO breaks down certain chemicals in the brain, like serotonin and norepinephrine. By blocking MAO, phenelzine helps increase the levels of these chemicals, which can improve mood.

Common Side Effects
mirtazapine
  • Feeling sleepy
  • Increased appetite
  • Weight gain
  • Dizziness
phenelzine
  • Dizziness
  • Headache
  • Drowsiness
  • Trouble sleeping
  • Tiredness
FAERS Reports
mirtazapine
  • Feeling sick to your stomach 4,838
  • Feeling tired 4,714
  • Accidentally falling down 4,026
  • Loose or watery stools 3,961
  • Harm from different substances 3,705
phenelzine
  • Feeling sad or hopeless 187
  • Head pain 136
  • Feeling worried or nervous 129
  • Gaining weight 120
  • Trouble sleeping 104
Serious Warnings
mirtazapine

Antidepressants may increase the risk of suicidal thoughts and behaviors in young adults. Your doctor should closely watch you for worsening depression or suicidal thoughts. Mirtazapine is not approved for use in children.

phenelzine

Antidepressants may increase the risk of suicidal thoughts and behavior in children, teens, and young adults. Your doctor will monitor you closely for worsening depression, suicidal thoughts, or unusual changes in behavior. Families and caregivers should also watch for these changes and report them to the doctor. This medicine is not approved for use in children.

Pregnancy
mirtazapine

Tell your doctor if you are pregnant or plan to become pregnant. Mirtazapine should be used during pregnancy only if clearly needed. Talk to your doctor if you are breastfeeding.

phenelzine

It is not known if phenelzine can harm an unborn baby. Talk to your doctor if you are pregnant, planning to become pregnant, or breastfeeding.

Also Compare, Nearby Drugs

Compare phenelzine with

How to Read This mirtazapine vs phenelzine Comparison

mirtazapine is classified in the Noradrenergic and Specific Serotonergic Antidepressant (NaSSA) drug class, while phenelzine sits within the Monoamine Oxidase Inhibitor (MAOI) class. Drugs from different classes work through distinct mechanisms, so a head-to-head comparison illustrates trade-offs rather than equivalence. Both drugs are prescription-only, so a licensed provider must authorize use.

Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, mirtazapine has 21,244 submissions while phenelzine has 676. Those figures reflect cumulative reporting volume, not per-patient risk, so older, widely dispensed drugs typically look worse on count alone. These two drugs have a known moderate interaction flagged in FDA labeling, attributed to both of these medicines increase the level of a brain chemical called serotonin. taking them together can cause serotonin to reach dangerous levels in the body.. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.

A table cannot substitute for clinical judgment. Effectiveness, tolerability, drug-drug interactions with your other medications, kidney and liver function, pregnancy status, insurance formulary, and price all feed into a decision that only a licensed prescriber can make responsibly. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This page is for educational purposes only, is not medical advice, and should not be used to self-switch between mirtazapine and phenelzine - always consult your physician or pharmacist first.

Important: This comparison is for informational purposes only. Drug effects vary between individuals. Always consult your doctor or pharmacist for personalized medical advice.