Pharmacologic class (EPC) · 4 drug pages

Thalidomide analog: adverse event reports filed with FDA

516,063 reports list a drug in this class as a suspect or interacting product, 2005–2026.

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.

516,063
reports across the class: 2.5% of all reports; 28,680
reports, 12 months to June 2026: 34,631 in the 12 months before; 63.4%
marked serious by the reporter: 57.4% across all reports; 4
drugs with a page: brand and generic names counted separately

Thalidomide analog 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 516,063 adverse event reports received by FDA, 2.5% of the database, from August 2005 to June 2026.

28,680 reports arrived in the 12 months to June 2026, down 17% from 34,631 in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. 63.4% of the class's reports are marked serious, 12.7% record death among the outcomes and 26.1% record hospitalisation, as reported.

Across the class the reactions recorded most often are diarrhoea (6.8%), fatigue (6.5%) and death (6.4%). 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
RevlimidLenalidomide	brand	354,649	8,112	62.3%	Diarrhoea
PomalystPomalidomide	brand	87,456	5,838	56.5%	Fatigue
Lenalidomide	generic	61,773	13,052	74.2%	Off label use
Pomalidomide	generic	12,185	1,678	93.5%	Plasma cell myeloma

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

Diarrhoealoose or frequent stools6.8%34,844
Fatiguetiredness6.5%33,701
Deaththe patient died; cause not stated by this term6.4%33,269
Pneumonialung infection4.8%24,890
Plasma cell myeloma4.7%24,022
Off label useused for a purpose or in a way not on the label4.3%22,283
Rashskin rash4.1%21,238
White blood cell count decreasedlow white cell count3%15,499
Neuropathy peripheralnerve damage in hands or feet2.8%14,353
Constipationconstipation2.6%13,496
Nauseafeeling sick2.5%12,845
Astheniaweakness or lack of energy2.4%12,478
Neutropenialow neutrophils, a type of white blood cell2.4%12,350
Product dose omission issuea dose was missed2.3%11,698
Platelet count decreasedlow platelet count2.2%11,193
Dyspnoeashortness of breath2%10,194
Dizzinesslight-headedness or unsteadiness1.8%9,365
Muscle spasmsmuscle cramps1.8%9,241
Thrombosis1.8%9,114
Full blood count decreased1.8%9,098
Falla fall1.7%9,007
Pruritusitching1.7%8,939
Anaemialow red blood cells1.7%8,918
Pyrexiafever1.7%8,789
Peripheral swellingswelling of the arms or legs1.6%8,441

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

Death12.7%65,404

Life-threatening1.9%9,786

Hospitalisation (initial or prolonged)26.1%134,895

Disability1%4,918

Congenital anomaly0%94

Other serious35.5%183,351

Not serious36.6%188,699

Patient age

Under 20%52

2 to 110%75

12 to 170%93

18 to 441.1%5,776

45 to 6417.1%88,163

65 to 7422.7%117,033

75 and over22.9%118,381

Age not given36.1%186,490

Who reported

Physician20.2%104,031

Pharmacist28.5%147,127

Other health professional31.5%162,355

Lawyer0%19

Consumer or non-health professional18.9%97,479

Not given1%5,052

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 Thalidomide analog reports

Which drugs are in the Thalidomide analog class on this site?

Revlimid, Pomalyst, Lenalidomide and Pomalidomide. Class membership comes from the pharmacologic class (EPC) on the drug's FDA label.

How many reports does the class have?

516,063 reports through June 2026, 28,680 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?

diarrhoea (6.8%), fatigue (6.5%), death (6.4%), pneumonia (4.8%) and plasma cell myeloma (4.7%).

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.