Drugs › Angiotensin 2 receptor blocker
Generic name
Losartan potassium: adverse event reports filed with FDA
6,725 reports list it as a suspect or interacting product, 2004–2026. Class: Angiotensin 2 receptor blocker. Also reported as Losartan Potassium Usp, Losartan Potassium Tablets, Losartan Potassium Tablets 50mg.
- 6,725
- reports as suspect product
- 0% of all reports · about 299 a year
- 246
- reports, 12 months to June 2026
- 296 in the 12 months before
- 73%
- marked serious by the reporter
- 67.6% across the class
- 5.5%
- record death among outcomes, as reported
- 373 reports · not verified by FDA
Between January 2004 and June 2026, 6,725 adverse event reports received by FDA list losartan potassium, a generic name as a suspect or interacting product. Reports that mention it only as a concomitant medication (45,229) are left out of every figure here.
In the 12 months to June 2026, 246 reports listed it, down 17% from 296 in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Over its reporting history that is about 299 reports a year and 0% of the 20,646,523 reports in the database, and 2.8% of the reports for the angiotensin 2 receptor blocker class. How many people take it is not in the data, so a count is not a rate of occurrence.
Reporters most often recorded drug ineffective (7.8%), dizziness (7.8%) and headache (5.9%). A report can list several reactions, so shares add to more than 100%; 1,147 different terms appear across these reports. Drug ineffective is recorded in 7.8% of these reports, a larger share than in the median angiotensin 2 receptor blocker drug (5.9%).
73% of the reports are marked serious by the reporter (67.6% across the class); 5.5% record death among the outcomes and 27.9% record hospitalisation, as reported. 45.6% of the reports came from consumers, and the largest patient age group is 45 to 64 (19.8%). FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event."
Reports by month, five years
Reports by the month FDA received them. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases.
By year received
2026 covers reports received through June 2026 only.
Reactions recorded in the reports
share of Losartan potassium reports recording the termmedian drug in angiotensin 2 receptor blocker
- Drug ineffectivethe medicine did not work as expected7.8%525
- Dizzinesslight-headedness or unsteadiness7.8%524
- Headachehead pain5.9%400
- Blood pressure increaseda raised blood pressure reading5.7%381
- Dyspnoeashortness of breath5.6%374
- Malaisegeneral feeling of being unwell4.8%320
- Hypertensionhigh blood pressure4.7%317
- Fatiguetiredness4.4%299
- Hypotensionlow blood pressure4.4%298
- Coughcough4.3%290
- Product substitution issuea problem after switching products3.9%264
- Nauseafeeling sick3.8%253
- Diarrhoealoose or frequent stools3.7%251
- Arthralgiajoint pain3.5%237
- Acute kidney injurysudden loss of kidney function3.2%212
- Drug interactionan interaction between medicines3%205
- Rashskin rash3%199
- Feeling abnormalfeeling odd or not right2.8%190
- Hyperkalaemiahigh blood potassium2.7%181
- Pruritusitching2.5%170
- Astheniaweakness or lack of energy2.5%166
- Falla fall2.5%166
- Painpain, site not specified2.4%161
- Abdominal pain upperupper stomach pain2.3%158
- Drug hypersensitivityan allergic-type reaction to a medicine2.3%157
- Back painback pain2.1%144
- Abdominal discomfortstomach discomfort2%136
- Pain in extremitypain in an arm or leg1.9%131
- Angioedemadeep swelling of skin or mucous membranes1.9%126
- Myalgiamuscle pain1.9%125
Top 30 of 1,147 MedDRA preferred terms recorded across these reports, with a plain-language gloss where one is available. One report can record several terms. The hollow bar is the median share across the 24 drugs in the angiotensin 2 receptor blocker class; it describes the reports, not the patients. 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."
Outcomes recorded
Outcome flags as the reporter set them; a report can carry several, and "other serious" is FDA's own category for serious reports outside the named outcomes. Grey bar: all 243,200 reports in the class. FDA has not verified any outcome and states that the reports "cannot be used to estimate the incidence of these events."
Patients and reporters
Patient age
Patient sex
Who reported
Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 47% of reports give the United States as the country of the event or reporter.
Reason for use recorded
| Indication as recorded (MedDRA) | Reports | Share |
|---|---|---|
| Hypertension | 2,502 | 37.2% |
| Blood pressure measurement | 128 | 1.9% |
| Blood pressure abnormal | 93 | 1.4% |
| Blood pressure increased | 68 | 1% |
| Ill-defined disorder | 45 | 0.7% |
| Essential hypertension | 44 | 0.7% |
The indication field is filled in by the reporter and is often blank; shares are of all 6,725 reports.
Drugs most often listed in the same reports
| Drug (any role in the report) | Reports | Share of Losartan potassium reports |
|---|---|---|
| Amlodipine | 524 | 7.8% |
| Aspirin | 468 | 7% |
| Hydrochlorothiazide | 451 | 6.7% |
| Furosemide | 415 | 6.2% |
| Simvastatin | 331 | 4.9% |
| Atorvastatin | 322 | 4.8% |
| Omeprazole | 313 | 4.7% |
| Atenolol | 251 | 3.7% |
| Metformin | 240 | 3.6% |
| Spironolactone | 184 | 2.7% |
Other products listed in reports where Losartan potassium is a suspect product, whatever their own role. Co-listing means the two were recorded together; it says nothing about either product's part in the event. Only the 2,500 most-reported names are counted here.
In context
| Measure | Losartan potassium | Angiotensin 2 receptor blocker | All reports |
|---|---|---|---|
| Reports as suspect product | 6,725 | 243,200 | 20,646,523 |
| Share of that pool | — | 2.8% | 0% |
| Reports, latest 12 months | 246 | — | 1,332,454 |
| Marked serious | 73% | 67.6% | 57.4% |
| Death recorded among outcomes, per 1,000 reports | 55 | 111 | 91 |
| Hospitalisation recorded, per 1,000 reports | 279 | 287 | 213 |
| Consumer-filed share | 45.6% | 54.2% | 45.8% |
| Top term, share of reports | Drug ineffective 7.8% | median 5.9% | 6.3% |
Shares are of reports, not of patients treated. The number of people taking a product is not in the data, so none of these figures is a rate, and differences between columns reflect who takes a product, who reports and how long it has been sold. 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."
Other drugs in the angiotensin 2 receptor blocker class
| Drug | Name type | Reports | Latest 12 months | Marked serious |
|---|---|---|---|---|
| Entresto | brand | 105,173 | 1,285 | 49.3% |
| Diovan | brand | 17,179 | 133 | 91.7% |
| Valsartan | generic | 16,935 | 923 | 83.8% |
| Losartan | generic | 15,176 | 1,137 | 80.1% |
| Candesartan | generic | 10,197 | 1,487 | 98.6% |
| Irbesartan | generic | 10,055 | 692 | 93.7% |
| Benicar | brand | 8,370 | 79 | 69.4% |
| Exforge | brand | 6,266 | 108 | 95.3% |
| Diovan HCT | brand | 5,670 | 30 | 95.3% |
| Filspari | brand | 5,598 | 2,908 | 16.1% |
| Candesartan cilexetil | generic | 5,311 | 622 | 97.6% |
| Cozaar | brand | 4,913 | 60 | 70.2% |
| Olmesartan medoxomil | generic | 4,777 | 169 | 90.6% |
| Telmisartan | generic | 4,666 | 357 | 91.2% |
| Atacand | brand | 4,597 | 48 | 76.6% |
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." A brand and its generic are separate rows because reporters name them separately.
Questions about Losartan potassium reports
How many adverse event reports has FDA received for Losartan potassium?
6,725 reports list Losartan potassium as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 246 of them arrived in the latest 12 months. Another 45,229 list it only as a concomitant medication.
What reactions are recorded in Losartan potassium reports?
drug ineffective (7.8%), dizziness (7.8%), headache (5.9%), blood pressure increased (5.7%) and dyspnoea (5.6%). These are MedDRA preferred terms coded from what the reporter described; a report can list several, and a term's presence is not a finding that Losartan potassium was responsible.
How serious are the reports?
73% are marked serious by the reporter. Among the outcomes recorded, 5.5% of reports include death and 27.9% include hospitalisation. FDA has not verified these outcomes and states that the reports "cannot be used to estimate the incidence" of the events.
Who files these reports?
consumer or non-health professional (45.6%), other health professional (24.5%) and physician (17%). Most reports reach FDA through the manufacturer, which must forward reports it receives.
Are reports for Losartan potassium rising?
246 reports in the 12 months to June 2026, down 17% from 296 in the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Counts also move with how many people take a product, its time on the market and publicity.
Do these reports show that Losartan potassium was responsible for these reactions?
No. FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event." The reaction may relate to the condition being treated, to other medicines, or to something else.
Is this a list of the side effects of Losartan potassium?
No. It is a count of what was reported to FDA. The adverse reactions observed in clinical studies are printed on the FDA-approved label, which a pharmacist or clinician can go through with you.
How do I report an adverse event?
Consumers and health professionals can report to FDA through MedWatch (Form FDA 3500 online, or 1-800-FDA-1088), or to the manufacturer, which must pass reports on. 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 report counts here when it lists Losartan potassium as a suspect or interacting product; reports listing it only as a concomitant medication (45,229) are excluded. 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.