What the label lists and what reports show
Hydrochlorothiazide and valsartan side effects
Hydrochlorothiazide and valsartan's FDA label: “The most common reasons for discontinuation of therapy with Diovan HCT were headache and dizziness.” FAERS holds 13,500 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 blood pressure increased (823 reports).
- Generic listed
- Boxed warning
Check it at the source: the hydrochlorothiazide and valsartan FDA label on DailyMed (effective February 13, 2026, Novartis Pharmaceuticals Corporation); the FDA FAERS public dashboard.
What does the patient leaflet say about side effects?
From the patient leaflet: What are the possible side effects of DIOVAN HCT?DIOVAN HCT may cause serious side effects including: Harm to an unborn baby causing injury and even death. See “ What is the most important information I should know about DIOVAN HCT? ” Low blood pressure (hypotension). Low blood pressure is most likely to happen if you: take water pills are on a low-salt diet get dialysis treatments have heart problems get sick with vomiting or diarrhea drink alcohol Lie down if you feel faint or dizzy. Call your doctor right away. Allergic reactions. People with and without allergy problems or asthma who take DIOVAN HCT may get allergic reactions. Worsening of Lupus. Hydrochlorothiazide, one of the medicines in DIOVAN HCT may cause Lupus to become active or worse. Fluid and electrolyte (salt) problems. […]
Source: FDA drug label, Novartis Pharmaceuticals Corporation, effective February 13, 2026 (SPL set d76a0419-05ee-437e-884c-65807aea9569), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsThe most common reasons for discontinuation of therapy with Diovan HCT were headache and dizziness.
From the label: adverse reactions, continuedThe most common reasons for discontinuation of therapy with Diovan HCT were headache and dizziness. The only adverse experience that occurred in ≥ 2% of patients treated with Diovan HCT and at a higher incidence than placebo was nasopharyngitis (2.4% vs. 1.9%). ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Novartis Pharmaceuticals Corporation at 1-888-669-6682 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical studies are conducted under widely varying conditions, adverse reactions rates observed in the clinical studies of a drug cannot be directly compared to rates in the clinical studies 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 Diovan HCT (valsartan and hydrochlorothiazide, USP) has been evaluated for safety in more than 5700 patients, including over 990 treated for over 6 months, and over 370 for over 1 year. Adverse experiences have generally been mild and transient in nature and have only infrequently required discontinuation of therapy. The overall incidence of adverse reactions with Diovan HCT was comparable to placebo. …
Source: FDA drug label, Novartis Pharmaceuticals Corporation, effective February 13, 2026 (SPL set d76a0419-05ee-437e-884c-65807aea9569), via openFDA; the full label on DailyMed
What do FAERS reports show?
13,500 reports list hydrochlorothiazide and valsartan among the medicines taken, each a report of something that happened, not proof the medicine caused it; 1,383 are coded as a death and 4,201 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 22 reactions below, 7 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
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms
What next?
- Hydrochlorothiazide and valsartan: 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