72/100 · Elevated
Manufactured by Alexion Pharmaceuticals Inc.
High Fatigue and Serious Adverse Events Associated with Eculizumab
94,110 FDA adverse event reports analyzed
Last updated: 2026-05-12
ECULIZUMAB is a medication tracked in the FDA Adverse Event Reporting System (FAERS), manufactured by Alexion Pharmaceuticals Inc.. Based on analysis of 94,110 FDA adverse event reports, ECULIZUMAB has a safety score of 72 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 ECULIZUMAB include FATIGUE, OFF LABEL USE, HAEMOGLOBIN DECREASED, HEADACHE, DEATH. This page provides a comprehensive breakdown of reported side effects, safety signals, patient demographics, and AI-powered safety analysis for ECULIZUMAB.
Eculizumab has a safety concern score of 72 out of 100, placing it in the elevated concern category based on analysis of FDA adverse event data. The FDA has received approximately 94,110 adverse event reports for this medication, which is primarily manufactured by Alexion Pharmaceuticals Inc..
The most commonly reported adverse events include Fatigue, Off Label Use, Haemoglobin Decreased. Of classified reports, 59.1% were designated as serious by the FDA, meaning they involved hospitalization, disability, or other significant medical outcomes. Fatigue is a common and serious adverse event, reported in over 6% of cases.
Serious adverse events account for nearly 60% of all reports, indicating significant health risks. Death and thrombotic microangiopathy are among the most severe reported outcomes.
Patients taking Eculizumab should monitor for the commonly reported side effects and contact their healthcare provider if they experience any unusual symptoms. Interactions with other drugs, particularly those affecting the immune system, should be carefully monitored. Warnings include the risk of thrombotic microangiopathy and death. This analysis is based on voluntary FDA adverse event reports and should not replace professional medical advice.
Eculizumab received a safety concern score of 72/100 (elevated concern). This is based on a 59.1% serious event ratio across 52,761 classified reports. The score accounts for 94,110 total adverse event reports and 100 distinct reaction types. This elevated score indicates a notable proportion of serious adverse events and warrants careful monitoring.
Adverse event reports by sex: Female: 24,942, Male: 16,800, Unknown: 766. The most frequently reported age groups are age 35 (225 reports), age 30 (224 reports), age 64 (217 reports). These demographics reflect reporting patterns and may not represent the full patient population.
Out of 52,761 classified reports for ECULIZUMAB:
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 reflect voluntary FDA adverse event reporting patterns and may not represent the full patient population.
Interactions with other drugs, particularly those affecting the immune system, should be carefully monitored. Warnings include the risk of thrombotic microangiopathy and death.
If you are taking Eculizumab, here are important things to know. The most commonly reported side effects include fatigue, off label use, haemoglobin decreased, headache, death. While many of these may be mild and temporary, you should contact your healthcare provider if any symptoms are severe or persistent. Patients should report any new or worsening symptoms to their healthcare provider immediately. Follow prescribed dosing instructions strictly to minimize the risk of serious adverse events. 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 oversight is ongoing, with the FDA requiring post-marketing studies to further assess long-term safety and efficacy.
The FDA has received approximately 94,110 adverse event reports associated with Eculizumab. 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.
The most frequently reported adverse events for Eculizumab include Fatigue, Off Label Use, Haemoglobin Decreased, Headache, Death. By volume, the top reported reactions are: Fatigue (5,822 reports), Off Label Use (4,574 reports), Haemoglobin Decreased (3,897 reports). These figures reflect FDA adverse event reports and may not represent the true incidence rate of these side effects in all patients taking Eculizumab.
Out of 52,761 classified reports, 31,168 (59.1%) were classified as serious and 21,593 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.
Adverse event reports for Eculizumab break down by patient sex as follows: Female: 24,942, Male: 16,800, Unknown: 766. 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.
The most frequently reported age groups for Eculizumab adverse events are: age 35: 225 reports, age 30: 224 reports, age 64: 217 reports, age 24: 215 reports, age 67: 213 reports. Age-related reporting patterns can reflect both the demographics of the patient population and potential age-related susceptibility to certain side effects.
The primary manufacturer associated with Eculizumab adverse event reports is Alexion Pharmaceuticals Inc.. Multiple manufacturers may produce generic versions of this drug. The manufacturer listed reflects the most frequently reported brand in FDA adverse event data.
Beyond the most common reactions, other reported adverse events for Eculizumab include: Pyrexia, Dyspnoea, Asthenia, Nausea, Drug Ineffective. Less common side effects can still be clinically significant. Patients should report any unusual symptoms to their healthcare provider.
You can report adverse events from Eculizumab 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.
Eculizumab has a safety concern score of 72 out of 100 (elevated 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. Fatigue is a common and serious adverse event, reported in over 6% of cases.
Key safety signals identified in Eculizumab's adverse event data include: Frequent reports of fatigue and other general symptoms suggest a need for careful patient monitoring.. Serious adverse events like death and thrombotic microangiopathy highlight the need for strict adherence to dosing guidelines.. The high volume of reports for serious conditions indicates a significant safety concern.. These signals are derived from patterns in FDA reports and should be discussed with a healthcare provider for personalized assessment.
Interactions with other drugs, particularly those affecting the immune system, should be carefully monitored. Warnings include the risk of thrombotic microangiopathy and death. Always inform your healthcare provider about all medications, supplements, and over-the-counter drugs you are taking before starting Eculizumab.
Patients should report any new or worsening symptoms to their healthcare provider immediately. Follow prescribed dosing instructions strictly to minimize the risk of serious adverse events.
Eculizumab has 94,110 adverse event reports on file with the FDA. Serious adverse events account for nearly 60% of all reports, indicating significant health risks. The volume of reports for Eculizumab reflects both the drug's usage level and the vigilance of the reporting community.
Regulatory oversight is ongoing, with the FDA requiring post-marketing studies to further assess long-term safety and efficacy. For the most current regulatory information, check the FDA's drug labeling database or consult your pharmacist.
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