What the label lists and what reports show

Irbesartan side effects

Irbesartan's FDA label: “The most common adverse reactions which were more frequent than placebo were hyperkalemia dizziness, orthostatic dizziness, and orthostatic hypotension.” FAERS holds 44,400 reports naming it through July 30, 2026; the reaction reported most often, leaving out the conditions it is used for, product-use terms and outcomes, is fatigue (2,546 reports).

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Check it at the source: the irbesartan FDA label on DailyMed (effective August 6, 2026, Macleods Pharmaceuticals Limited); the FDA FAERS public dashboard.

What does the label list?

From the label: adverse reactions
The most common adverse reactions which were more frequent than placebo were hyperkalemia dizziness, orthostatic dizziness, and orthostatic hypotension.

From the label: adverse reactions, continued
The following important adverse reactions are described elsewhere in the labeling: • Hypotension in Volume or Salt-Depleted Patients [see Warnings and Precautions ( 5.2 )] • Impaired Renal Function [see Warnings and Precautions ( 5.3 )] • Nephropathy in type 2 diabetic patients: The most common adverse reactions which were more frequent than placebo were hyperkalemia dizziness, orthostatic dizziness, and orthostatic hypotension. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Macleods Pharma USA, Inc. at 1-888-943-3210 or 1-855-926-3384 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. The adverse reaction information from clinical trials does, however, provide a basis for identifying the adverse events that appear to be related to drug use and for approximating rates. Hypertension Irbesartan tablets has been evaluated for safety in more than 4300 patients with hypertension and about 5000 subjects overall. This experience includes 1303 patients treated for over 6 months and 407 patients for 1 year or more.

Source: FDA drug label, Macleods Pharmaceuticals Limited, effective August 6, 2026 (SPL set e8635a1c-ae06-4e23-99f7-e704f91d6f43), via openFDA; the full label on DailyMed

What do FAERS reports show?

44,400 reports list irbesartan among the medicines taken, each a report of something that happened, not proof the medicine caused it; 3,301 are coded as a death and 18,987 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Of the 21 reactions below, 5 are named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.

Reports received each year

The 25 most reported reactions

Fatigue (named in the label)2,546
Nausea2,486
Diarrhoea (named in the label)2,338
Drug Ineffective (a use or a product term, not a reaction)2,205
Acute Kidney Injury2,151
Dizziness (named in the label)2,032
Dyspnoea2,025
Fall2,005
Headache1,942
Asthenia1,745
Off Label Use (a use or a product term, not a reaction)1,739
Malaise1,677
Pain1,571
Vomiting1,571
Blood Pressure Increased1,526
Cough (named in the label)1,495
Hypotension (named in the label)1,474
Arthralgia1,408
Hypertension (a use or a product term, not a reaction)1,307
Weight Decreased1,224
Rash1,184
Pyrexia1,181
Drug Interaction (a use or a product term, not a reaction)1,175
Pain In Extremity1,156
Pruritus1,149

Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms

What next?

Irbesartan: the full record: label, generics, price, shortages, recalls
Report a side effect to the FDA: MedWatch
Side effects hub: the most reported medicines and reactions