Pharmacologic class (EPC) · 4 drug pages

Microtubule inhibitor: adverse event reports filed with FDA

147,067 reports list a drug in this class as a suspect or interacting product, 2004–2026.

Read first · FDA's statement on these data

Adverse event reports submitted to FDA do not undergo extensive validation or verification. Therefore, a causal relationship cannot be established between product and reactions listed in a report. While a suspected relationship may exist, it is not medically validated and should not be the sole source of information for clinical decision making or other assumptions about the safety or efficacy of a product. Additionally, it is important to remember that adverse event reports represent a small percentage of total usage numbers of a product. Common products may have a higher number of adverse events due to the higher total number of people using the product. openFDA, FDA

FDA adds: "There is no certainty that the reported event (adverse event or medication error) was actually due to the product. FDA does not require that a causal relationship between a product and event be proven, and reports do not always contain enough detail to properly evaluate an event." The information in these reports "cannot be used to estimate the incidence of these events."

Do not rely on openFDA to make decisions regarding medical care. While we make every effort to ensure that data is accurate, you should assume all results are unvalidated.

Not medical advice. This site counts what was reported to FDA. Questions about a medicine or device belong with a pharmacist or clinician.

147,067
reports across the class: 0.7% of all reports; 12,139
reports, 12 months to June 2026: 12,890 in the 12 months before; 88.7%
marked serious by the reporter: 57.4% across all reports; 4
drugs with a page: brand and generic names counted separately

Microtubule inhibitor is a pharmacologic class (an FDA Established Pharmacologic Class) with 4 drug pages on this site. Together those drugs are listed as a suspect or interacting product in 147,067 adverse event reports received by FDA, 0.7% of the database, from January 2004 to June 2026.

12,139 reports arrived in the 12 months to June 2026, close to the 12,890 of the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. 88.7% of the class's reports are marked serious, 14.7% record death among the outcomes and 37.4% record hospitalisation, as reported.

Across the class the reactions recorded most often are alopecia (12.6%), diarrhoea (6.4%) and neutropenia (5.8%). The class median share shown beside each term is the middle value across the member drugs; it is the comparison used on every drug page in this class.

The members table is ordered by report count for navigation only. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Drugs in the class

Drug	Name type	Reports	Latest 12 months	Marked serious	Top term recorded
Paclitaxel	generic	69,395	8,417	97.4%	Dyspnoea
Docetaxel	generic	59,411	3,173	76.9%	Alopecia
AbraxanePaclitaxel	brand	15,105	483	93.8%	Death
HalavenEribulin mesylate	brand	3,156	66	93.1%	Neutropenia

Ordered by report count for navigation only. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Reports by month, five years

FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases.

Reactions recorded across the class

share of class reports recording the termmedian drug in the class

Alopeciahair loss12.6%18,566
Diarrhoealoose or frequent stools6.4%9,440
Neutropenialow neutrophils, a type of white blood cell5.8%8,491
Nauseafeeling sick5.7%8,416
Dyspnoeashortness of breath4.6%6,816
Madarosis4.6%6,740
Fatiguetiredness4.5%6,662
Febrile neutropeniafever with low white blood cells4.4%6,500
Anaemialow red blood cells4.4%6,438
Malignant neoplasm progression4.2%6,130
Off label useused for a purpose or in a way not on the label4.2%6,116
Vomitingbeing sick4.1%6,080
Hair texture abnormal4.1%5,997
Hair colour changes4%5,878
Pyrexiafever3.9%5,706
Hair disorder3.8%5,636
Myelosuppression3.8%5,590
Disease progressionthe disease advanced3.8%5,525
Neuropathy peripheralnerve damage in hands or feet3.6%5,266
Deaththe patient died; cause not stated by this term3.4%5,022
Astheniaweakness or lack of energy3%4,406
Thrombocytopenialow platelets2.8%4,068
Drug ineffectivethe medicine did not work as expected2.6%3,799
Anxietyanxiety2.5%3,718
Decreased appetitereduced appetite2.5%3,617

Solid bar: share of all class reports. Hollow bar: the median share across the 4 member drugs, the reference used on each member's page. One report can record several terms.

Outcomes, patients and reporters

Outcomes recorded

Death14.7%21,681

Life-threatening6.8%10,073

Hospitalisation (initial or prolonged)37.4%55,042

Disability3%4,458

Congenital anomaly0.2%263

Other serious53.8%79,063

Not serious11.3%16,672

Patient age

Under 20.1%133

2 to 110.1%156

12 to 170.2%351

18 to 449.4%13,808

45 to 6434.7%51,012

65 to 7419.6%28,780

75 and over8.1%11,891

Age not given27.8%40,936

Who reported

Physician39.3%57,774

Pharmacist6.7%9,905

Other health professional34.9%51,397

Lawyer8.5%12,489

Consumer or non-health professional8.6%12,669

Not given1.9%2,833

Grey bar: all 20,646,523 reports in the database. Outcome flags are as the reporter set them and are not verified by FDA.

Questions about Microtubule inhibitor reports

Which drugs are in the Microtubule inhibitor class on this site?

Paclitaxel, Docetaxel, Abraxane and Halaven. Class membership comes from the pharmacologic class (EPC) on the drug's FDA label.

How many reports does the class have?

147,067 reports through June 2026, 12,139 of them in the latest 12 months. A report listing two drugs of the class counts once for each.

What reactions are recorded most often?

alopecia (12.6%), diarrhoea (6.4%), neutropenia (5.8%), nausea (5.7%) and dyspnoea (4.6%).

Can the members table be used to rank the drugs?

No. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic." Drugs differ in how many people take them, in the conditions they treat, in time on the market and in how diligently reports are collected.

How do I report an adverse event?

Through FDA MedWatch (Form FDA 3500, or 1-800-FDA-1088) or to the manufacturer. See the guide on how to report.

Where this comes from. Counts are built from the openFDA Drug Adverse Event (FAERS) bulk export released 28 Sep 2026, which holds reports FDA received through 30 Jun 2026. Drug names are as reported, resolved to the brand or generic name on the FDA label where openFDA's harmonisation matched them; classes are the pharmacologic class (EPC) from the label and the National Drug Code Directory of 17 Sep 2026. A class is the Established Pharmacologic Class most often attached to a drug's reports by openFDA's label harmonisation, or from the NDC Directory where reports carry none. No report narrative, lot number, patient detail or reporter identity is published. See the methodology and sources; FDA's record is authoritative, and corrections are handled within five working days.

Drug data (FAERS) through 30 Jun 2026; device data (MAUDE) through 31 Aug 2026. Not medical advice.