MIRTAZAPINE

85/100 · Critical

Manufactured by Organon LLC

High Safety Concerns with Mirtazapine, Particularly for Serious Reactions

174,805 FDA adverse event reports analyzed

Last updated: 2026-05-12

About MIRTAZAPINE

MIRTAZAPINE is a medication tracked in the FDA Adverse Event Reporting System (FAERS), manufactured by Organon LLC. Based on analysis of 174,805 FDA adverse event reports, MIRTAZAPINE has a safety score of 85 out of 100. This score indicates a relatively favorable safety profile, with fewer or less severe adverse events compared to many other tracked medications. The most commonly reported adverse reactions for MIRTAZAPINE include NAUSEA, FATIGUE, DRUG INEFFECTIVE, FALL, DIARRHOEA. This page provides a comprehensive breakdown of reported side effects, safety signals, patient demographics, and AI-powered safety analysis for MIRTAZAPINE.

AI Safety Analysis

Mirtazapine has a safety concern score of 85 out of 100, placing it in the high concern category based on analysis of FDA adverse event data. The FDA has received approximately 174,805 adverse event reports for this medication, which is primarily manufactured by Organon Llc.

The most commonly reported adverse events include Nausea, Fatigue, Drug Ineffective. Of classified reports, 83.8% were designated as serious by the FDA, meaning they involved hospitalization, disability, or other significant medical outcomes. Mirtazapine has a high incidence of serious adverse reactions, with over 73,550 serious reports out of 174,805 total reports.

The most common reactions include nausea, fatigue, and drug ineffectiveness, which are reported in over 4,000 cases each. Serious reactions such as death, pneumonia, and suicidal ideation are frequently reported, indicating significant safety concerns.

Patients taking Mirtazapine should monitor for the commonly reported side effects and contact their healthcare provider if they experience any unusual symptoms. Mirtazapine can interact with various drugs, including other antidepressants and sedatives, and can lead to serious adverse events such as serotonin syndrome and QT prolongation. This analysis is based on voluntary FDA adverse event reports and should not replace professional medical advice.

Safety Score: 85/100

Mirtazapine received a safety concern score of 85/100 (high concern). This is based on a 83.8% serious event ratio across 87,736 classified reports. The score accounts for 174,805 total adverse event reports and 100 distinct reaction types. This high score reflects a significant proportion of serious adverse events in the reporting data.

Top Adverse Reactions

NAUSEA4,837 reports
FATIGUE4,714 reports
DRUG INEFFECTIVE4,596 reports
FALL4,027 reports
DIARRHOEA3,959 reports
OFF LABEL USE3,836 reports
TOXICITY TO VARIOUS AGENTS3,703 reports
ANXIETY3,470 reports
DIZZINESS3,430 reports
DYSPNOEA3,394 reports
DEATH3,322 reports
DRUG INTERACTION3,249 reports
DEPRESSION3,207 reports
VOMITING3,191 reports
HEADACHE3,058 reports
SOMNOLENCE2,992 reports
ASTHENIA2,911 reports
INSOMNIA2,908 reports
CONFUSIONAL STATE2,881 reports
PAIN2,850 reports
MALAISE2,643 reports
DECREASED APPETITE2,387 reports
COMPLETED SUICIDE2,328 reports
SUICIDAL IDEATION2,304 reports
WEIGHT DECREASED2,163 reports
CONDITION AGGRAVATED2,158 reports
TREMOR2,157 reports
ARTHRALGIA2,118 reports
PNEUMONIA2,084 reports
PYREXIA2,040 reports
OVERDOSE1,988 reports
WEIGHT INCREASED1,957 reports
HYPOTENSION1,903 reports
INTENTIONAL OVERDOSE1,863 reports
DRUG ABUSE1,825 reports
CONSTIPATION1,814 reports
SUICIDE ATTEMPT1,813 reports
AGITATION1,786 reports
ABDOMINAL PAIN1,649 reports
ACUTE KIDNEY INJURY1,643 reports
GAIT DISTURBANCE1,549 reports
TACHYCARDIA1,545 reports
PAIN IN EXTREMITY1,470 reports
HYPERTENSION1,460 reports
URINARY TRACT INFECTION1,455 reports
FEELING ABNORMAL1,410 reports
RASH1,408 reports
HYPONATRAEMIA1,379 reports
COUGH1,376 reports
HYPERHIDROSIS1,368 reports
LOSS OF CONSCIOUSNESS1,337 reports
BACK PAIN1,316 reports
SEROTONIN SYNDROME1,295 reports
GENERAL PHYSICAL HEALTH DETERIORATION1,283 reports
PRURITUS1,283 reports
ANAEMIA1,276 reports
PRODUCT USE IN UNAPPROVED INDICATION1,254 reports
COMA1,244 reports
HALLUCINATION1,195 reports
MUSCLE SPASMS1,192 reports
DEHYDRATION1,185 reports
MYALGIA1,149 reports
ABDOMINAL PAIN UPPER1,145 reports
SEIZURE1,132 reports
SYNCOPE1,124 reports
CHEST PAIN1,113 reports
PARAESTHESIA1,080 reports
ELECTROCARDIOGRAM QT PROLONGED1,072 reports
BLOOD PRESSURE INCREASED1,059 reports
DYSPHAGIA1,021 reports
VISION BLURRED1,002 reports
OEDEMA PERIPHERAL990 reports
AGGRESSION966 reports
BALANCE DISORDER961 reports
SEPSIS947 reports
RENAL FAILURE943 reports
MEMORY IMPAIRMENT926 reports
SLEEP DISORDER924 reports
PALPITATIONS920 reports
INTENTIONAL SELF INJURY910 reports
DEPRESSED LEVEL OF CONSCIOUSNESS902 reports
HYPOAESTHESIA899 reports
DYSKINESIA874 reports
PRODUCT DOSE OMISSION ISSUE866 reports
RESTLESSNESS865 reports
DELIRIUM857 reports
DIABETES MELLITUS841 reports
CHILLS817 reports
CARDIAC ARREST812 reports
DISORIENTATION799 reports
CHRONIC KIDNEY DISEASE784 reports
ABDOMINAL DISCOMFORT780 reports
DEPRESSED MOOD760 reports
PERIPHERAL SWELLING760 reports
MUSCULAR WEAKNESS754 reports
DRY MOUTH736 reports
HEART RATE INCREASED730 reports
DISTURBANCE IN ATTENTION724 reports
PULMONARY EMBOLISM714 reports
COVID 19709 reports

Key Safety Signals

  • High rate of serious adverse events (83.8%)
  • Multiple reports of suicidal ideation and completed suicide
  • Significant number of drug interactions and overdose reports

Patient Demographics

Adverse event reports by sex: Female: 46,485, Male: 34,181, Unknown: 236. The most frequently reported age groups are age 59 (1,286 reports), age 72 (1,283 reports), age 68 (1,236 reports). These demographics reflect reporting patterns and may not represent the full patient population.

Report Outcomes

Out of 87,736 classified reports for MIRTAZAPINE:

  • Serious: 73,550 reports (83.8%) — includes hospitalization, disability, life-threatening events, or death
  • Non-Serious: 14,186 reports (16.2%)
Serious 83.8%Non-Serious 16.2%

The FDA classifies an adverse event as “serious” if it results in death, hospitalization, disability, congenital anomaly, or requires intervention to prevent permanent damage.

Demographics Breakdown

Reports by Sex

Female46,485 (57.5%)
Male34,181 (42.2%)
Unknown236 (0.3%)

Reports by Age

Age 591,286 reports
Age 721,283 reports
Age 681,236 reports
Age 651,235 reports
Age 691,229 reports
Age 671,225 reports
Age 601,198 reports
Age 551,191 reports
Age 741,189 reports
Age 581,173 reports
Age 661,155 reports
Age 621,153 reports
Age 731,134 reports
Age 571,131 reports
Age 701,124 reports
Age 611,113 reports
Age 631,113 reports
Age 761,109 reports
Age 531,097 reports
Age 641,097 reports

Demographics reflect voluntary FDA adverse event reporting patterns and may not represent the full patient population.

Drug Interactions & Warnings

Mirtazapine can interact with various drugs, including other antidepressants and sedatives, and can lead to serious adverse events such as serotonin syndrome and QT prolongation.

What You Should Know

If you are taking Mirtazapine, here are important things to know. The most commonly reported side effects include nausea, fatigue, drug ineffective, fall, diarrhoea. While many of these may be mild and temporary, you should contact your healthcare provider if any symptoms are severe or persistent. Patients should be closely monitored for signs of suicidal ideation and behavior, especially during the first few weeks of treatment. Avoid driving or operating heavy machinery until the effects of the medication are known, as dizziness and fatigue are common. If you experience a serious adverse reaction, seek emergency medical attention immediately or call 911. You can report side effects to the FDA's MedWatch program at 1-800-FDA-1088.

Regulatory Context

The FDA closely monitors Mirtazapine due to its high rate of serious adverse events, and healthcare providers should be vigilant in monitoring patients for signs of serious reactions.

Frequently Asked Questions

How many adverse event reports has the FDA received for Mirtazapine?

The FDA has received approximately 174,805 adverse event reports associated with Mirtazapine. These reports come from healthcare professionals, consumers, and manufacturers through the FDA Adverse Event Reporting System (FAERS). Note that the number of reports does not directly indicate the frequency of side effects, as adverse events are voluntarily reported and may be underrepresented.

What are the most commonly reported side effects of Mirtazapine?

The most frequently reported adverse events for Mirtazapine include Nausea, Fatigue, Drug Ineffective, Fall, Diarrhoea. By volume, the top reported reactions are: Nausea (4,837 reports), Fatigue (4,714 reports), Drug Ineffective (4,596 reports). These figures reflect FDA adverse event reports and may not represent the true incidence rate of these side effects in all patients taking Mirtazapine.

What percentage of Mirtazapine adverse event reports are serious?

Out of 87,736 classified reports, 73,550 (83.8%) were classified as serious and 14,186 as non-serious. The FDA classifies an event as "serious" if it results in death, hospitalization, disability, or other medically significant outcomes. A higher serious-event ratio warrants closer attention but does not necessarily mean the drug is unsafe.

Who reports adverse events for Mirtazapine (by sex)?

Adverse event reports for Mirtazapine break down by patient sex as follows: Female: 46,485, Male: 34,181, Unknown: 236. This distribution reflects reporting patterns rather than actual risk differences between groups. Reporting rates can be influenced by prescribing patterns, disease demographics, and reporting behavior.

What age groups report the most side effects for Mirtazapine?

The most frequently reported age groups for Mirtazapine adverse events are: age 59: 1,286 reports, age 72: 1,283 reports, age 68: 1,236 reports, age 65: 1,235 reports, age 69: 1,229 reports. Age-related reporting patterns can reflect both the demographics of the patient population and potential age-related susceptibility to certain side effects.

Who manufactures Mirtazapine?

The primary manufacturer associated with Mirtazapine adverse event reports is Organon Llc. Multiple manufacturers may produce generic versions of this drug. The manufacturer listed reflects the most frequently reported brand in FDA adverse event data.

What other side effects have been reported for Mirtazapine?

Beyond the most common reactions, other reported adverse events for Mirtazapine include: Off Label Use, Toxicity To Various Agents, Anxiety, Dizziness, Dyspnoea. Less common side effects can still be clinically significant. Patients should report any unusual symptoms to their healthcare provider.

How do I report a side effect from Mirtazapine?

You can report adverse events from Mirtazapine to the FDA through their MedWatch program at www.fda.gov/medwatch, by calling 1-800-FDA-1088, or by completing Form FDA 3500. Healthcare professionals, consumers, and manufacturers can all submit reports. Reporting helps the FDA monitor drug safety after approval.

What is Mirtazapine's safety score and what does it mean?

Mirtazapine has a safety concern score of 85 out of 100 (high concern). This score is calculated from the ratio of serious to non-serious adverse events, the diversity of reported reactions, and the overall volume of reports relative to usage. Mirtazapine has a high incidence of serious adverse reactions, with over 73,550 serious reports out of 174,805 total reports.

What are the key safety signals for Mirtazapine?

Key safety signals identified in Mirtazapine's adverse event data include: High rate of serious adverse events (83.8%). Multiple reports of suicidal ideation and completed suicide. Significant number of drug interactions and overdose reports. These signals are derived from patterns in FDA reports and should be discussed with a healthcare provider for personalized assessment.

Does Mirtazapine interact with other drugs?

Mirtazapine can interact with various drugs, including other antidepressants and sedatives, and can lead to serious adverse events such as serotonin syndrome and QT prolongation. Always inform your healthcare provider about all medications, supplements, and over-the-counter drugs you are taking before starting Mirtazapine.

What should patients know before taking Mirtazapine?

Patients should be closely monitored for signs of suicidal ideation and behavior, especially during the first few weeks of treatment. Avoid driving or operating heavy machinery until the effects of the medication are known, as dizziness and fatigue are common.

Are Mirtazapine side effects well-documented?

Mirtazapine has 174,805 adverse event reports on file with the FDA. The most common reactions include nausea, fatigue, and drug ineffectiveness, which are reported in over 4,000 cases each. The volume of reports for Mirtazapine reflects both the drug's usage level and the vigilance of the reporting community.

What is the FDA's position on Mirtazapine?

The FDA closely monitors Mirtazapine due to its high rate of serious adverse events, and healthcare providers should be vigilant in monitoring patients for signs of serious reactions. For the most current regulatory information, check the FDA's drug labeling database or consult your pharmacist.

Related Drugs

Drugs related to MIRTAZAPINE based on therapeutic use, drug class, or shared indications:

SertralineFluoxetineParoxetineVenlafaxineAmitriptyline
Important Disclaimer: This content is generated by AI analysis of FDA adverse event reports and is provided for informational purposes only. It is not medical advice. Adverse event reports submitted to the FDA do not prove that a medication caused the reported side effect. Always consult your healthcare provider before starting, stopping, or changing any medication. If you experience a serious side effect, contact your doctor or call 911 immediately.