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Quick facts
- How it is given
- oral
- Type
- human prescription drug
- RxNorm ID
- 349405
We do not publish dosing. How much of this medicine to take, how often, and for how long depends on your age, weight, kidney and liver function, other conditions and other medicines. That is a decision for the person who prescribes or dispenses it. Follow the directions on your own pack and ask your pharmacist if anything is unclear.
What it is used to treat
Olmesartan medoxomil tablets are indicated for the treatment of hypertension in adults and children six years of age and older, to lower blood pressure. Lowering blood pressure reduces the risk of fatal and nonfatal cardiovascular events, primarily strokes and myocardial infarctions. These benefits have been seen in controlled trials of antihypertensive drugs from a wide variety of pharmacologic classes including the class to which this drug principally belongs. There are no controlled trials demonstrating risk reduction with olmesartan medoxomil tablets. Control of high blood pressure should be part of comprehensive cardiovascular risk management, including, as appropriate, lipid control, diabetes management, antithrombotic therapy, smoking cessation, exercise, and limited sodium intake. Many patients will require more than one drug to achieve blood pressure goals. For specific advice on goals and management, see published guidelines, such as those of the National High Blood Pressure Education Program’s Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC). Numerous antihypertensive drugs, from a variety of pharmacologic classes and with different mechanisms of action, have been shown in randomized controlled trials to reduce cardiovascular morbidity and mortality, and it can be concluded that it is blood pressure reduction, and not some other pharmacologic property of the drugs, that is largely responsible for those benefits. The largest and most consistent cardiovascular outcome benefit has been a reduction in the risk of stroke, but reductions in myocardial infarction and cardiovascular mortality also have been seen regularly. Elevated systolic or diastolic pressure causes increased cardiovascular risk, and the absolute risk increase per mmHg is greater at higher blood pressures, so that even modest reductions of severe hypertension can provide substantial benefit. […]
About this medicine
Olmesartan medoxomil,USP a prodrug, is hydrolyzed to olmesartan during absorption from the gastrointestinal tract. Olmesartan is a selective AT1 subtype angiotensin II receptor antagonist. Olmesartan medoxomil is described chemically as 2,3-dihydroxy-2-butenyl 4-(1 hydroxy-1-methylethyl)-2-propyl-1-[p-(o-1H-tetrazol-5-ylphenyl)benzyl]imidazole5-carboxylate, cyclic 2,3-carbonate. Its empirical formula is C 29 H 30 N 6 O 6 and its structural formula is: Olmesartan medoxomil, USP is a white to off-white crystalline powder with a molecular weight of 558.59. It is practically insoluble in water and in heptanes,slightly soluble in ethanol (96%),sparingly soluble in methanol. Olmesartan medoxomil tablets, USP is available for oral use as film-coated tablets containing 5 mg, 20 mg, or 40 mg of olmesartan medoxomil,USP and the following inactive ingredients: lactose monohydrate, microcrystalline cellulose, low-substituted hydroxypropyl cellulose, hydroxy propyl cellulose ,stearic acid,magnesium stearate, talc, titanium dioxide, and (5 mg only) yellow iron oxide. If the product complies with this test, the labeling indicates that it meets USP Dissolution Test 6. Structure
How it works
12.1 Mechanism of Action Angiotensin II is formed from angiotensin I in a reaction catalyzed by angiotensin converting enzyme (ACE, kininase II). Angiotensin II is the principal pressor agent of the renin-angiotensin system, with effects that include vasoconstriction, stimulation of synthesis and release of aldosterone, cardiac stimulation and renal reabsorption of sodium. Olmesartan blocks the vasoconstrictor effects of angiotensin II by selectively blocking the binding of angiotensin II to the AT1 receptor in vascular smooth muscle. Its action is, therefore, independent of the pathways for angiotensin II synthesis. An AT2 receptor is found also in many tissues, but this receptor is not known to be associated with cardiovascular homeostasis. Olmesartan has more than a 12,500-fold greater affinity for the AT1 receptor than for the AT2 receptor. Blockade of the renin-angiotensin system with ACE inhibitors, which inhibit the biosynthesis of angiotensin II from angiotensin I, is a mechanism of many drugs used to treat hypertension. ACE inhibitors also inhibit the degradation of bradykinin, a reaction also catalyzed by ACE. Because olmesartan medoxomil does not inhibit ACE (kininase II), it does not affect the response to bradykinin. Whether this difference has clinical relevance is not yet known. Blockade of the angiotensin II receptor inhibits the negative regulatory feedback of angiotensin II on renin secretion, but the resulting increased plasma renin activity and circulating angiotensin II levels do not overcome the effect of olmesartan on blood pressure.
Who should not take it
Do not co-administer aliskiren with olmesartan medoxomil tablets in patients with diabetes [see Drug Interactions ( 7.3 ) ]. Do not co-administer aliskiren with olmesartan medoxomil tablets in patients with diabetes.
Warnings and cautions
· Avoid fetal (in utero) exposure ( 5.1 ). · Use of olmesartan medoxomil tablets in children less than 1 year of age is not recommended.( 5.2 ). · Observe for signs and symptoms of hypotension in volume- or salt-depleted patients with treatment initiation ( 5.3 ). · Monitor for worsening renal function in patients with renal impairment ( 5.4 ). · Sprue-like enteropathy has been reported. Consider alternative antihypertensive therapy in cases where no other etiology is found ( 5.5 ). 5.1 Fetal Toxicity Olmesartan medoxomil tablets can cause fetal harm when administered to a pregnant woman. Use of drugs that act on the renin-angiotensin system (RAS) during the second and third trimesters of pregnancy reduces fetal renal function and increases fetal and neonatal morbidity and death. Resulting oligohydramnios can be associated with fetal lung hypoplasia and skeletal deformations. Potential neonatal adverse effects include skull hypoplasia, anuria, hypotension, renal failure, and death. When pregnancy is detected, discontinue olmesartan medoxomil tablets as soon as possible [see Use in Specific Populations ( 8.1 ) ]. 5.2 Morbidity in Infants Use of olmesartan medoxomil tablets in children less than 1 year of age is not recommended. Drugs that act directly on the renin-angiotensin-aldosterone system (RAAS) can have effects on the development of immature kidneys [see Use in Specific Populations ( 8.4 ) ]. 5.3 Hypotension in Volume-or Salt-Depleted Patients In patients with an activated renin-angiotensin-aldosterone system, such as volume- and/or salt-depleted patients (e.g., those being treated with high doses of diuretics), symptomatic hypotension may be anticipated after initiation of treatment with olmesartan medoxomil tablets . Initiate treatment under close medical supervision and consider starting at a lower dose. If hypotension does occur, place the patient in the supine position and, if necessary, give an intravenous infusion of normal saline [see Dosage and Administration ( 2.1 ) ]. A transient hypotensive response is not a contraindication to further treatment, which usually can be continued without difficulty once the blood pressure has stabilized. […]
Reported side effects
The most common adverse reaction in adults was dizziness (3%) ( 6.1 ). To report SUSPECTED ADVERSE REACTIONS, contact Ascend Laboratories, LLC at 1-877-272-7901 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 reaction 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. Adult Hypertension Olmesartan medoxomil tablets has been evaluated for safety in more than 3825 patients/subjects, including more than 3275 patients treated for hypertension in controlled trials. This experience included about 900 patients treated for at least 6 months and more than 525 for at least 1 year. Events generally were mild, transient and had no relationship to the dose of olmesartan medoxomil tablets. Analysis of gender, age and race groups demonstrated no differences between olmesartan medoxomil tablets and placebo-treated patients. The rate of withdrawals due to adverse reactions in all trials of hypertensive patients was 2.4% (i.e., 79/3278) of patients treated with olmesartan medoxomil tablets and 2.7% (i.e., 32/1179) of control patients. In placebo-controlled trials, the only adverse reaction that occurred in more than 1% of patients treated with olmesartan medoxomil tablets and at a higher incidence versus placebo was dizziness (3% vs. 1%). Facial edema was reported in five patients receiving olmesartan medoxomil tablets. Angioedema has been reported with angiotensin II antagonists. Pediatric Hypertension No relevant differences were identified between the adverse experience profile for pediatric patients aged 1 to 16 years and that previously reported for adult patients. 6.2 Post-Marketing Experience The following adverse reactions have been reported in post-marketing experience. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. […]
Interactions with other medicines
Agents increasing potassium levels may lead to increase in serum potassium ( 7.1 ). NSAID use may lead to increased risk of renal impairment and loss of antihypertensive effect ( 7.2 ). Dual inhibition of the renin-angiotensin system: Increased risk of renal impairment, hypotension, and hyperkalemia ( 7.3 ). Lithium: Increases in serum lithium concentrations and lithium toxicity ( 7.4 ). Colesevelam hydrochloride: Consider administering olmesartan at least 4 hours before colesevelam hydrochloride dose ( 7.5 ). 7.1 Agents Increasing Serum Potassium Concomitant use of olmesartan with other agents that block the renin-angiotensin system, potassium-sparing diuretics (e.g., spironolactone, triamterene, amiloride), potassium supplements, salt substitutes containing potassium or other drugs that may increase potassium levels (e.g., heparin) may lead to increases in serum potassium. If co-medication is considered necessary, monitoring of serum potassium is advisable. 7.2 Non-Steroidal Anti-Inflammatory Agents Including Selective Cyclooxygenase-2 Inhibitors (COX-2 Inhibitors) In patients who are elderly, volume-depleted (including those on diuretic therapy), or with compromised renal function, co-administration of NSAIDs, including selective COX-2 inhibitors, with angiotensin II receptor antagonists, including olmesartan medoxomil, may result in deterioration of renal function, including possible acute renal failure. These effects are usually reversible. Monitor renal function periodically in patients receiving olmesartan medoxomil and NSAID therapy. The antihypertensive effect of angiotensin II receptor antagonists, including olmesartan medoxomil, may be attenuated by NSAIDs including selective COX-2 inhibitors. 7.3 Dual Blockade of the Renin-Angiotensin System (RAS) Dual blockade of the RAS with angiotensin receptor blockers, ACE inhibitors, or aliskiren is associated with increased risks of hypotension, hyperkalemia, and changes in renal function (including acute renal failure) compared to monotherapy. Most patients receiving the combination of two RAS inhibitors do not obtain any additional benefit compared to monotherapy. […]
Use in specific groups
• Lactation: Choose to discontinue nursing or drug (8.2 ). 8.1 Pregnancy Risk Summary Olmesartan medoxomil tablets can cause fetal harm when administered to a pregnant woman. Use of drugs that act on the renin-angiotensin system during the second and third trimesters of pregnancy reduces fetal renal function and increases fetal and neonatal morbidity and death. Most epidemiologic studies examining fetal abnormalities after exposure to antihypertensive use in the first trimester have not distinguished drugs affecting the renin-angiotensin system from other antihypertensive agents. In animal reproduction studies, olmesartan medoxomil tablets treatment during organogenesis resulted in increased embryofetal toxicity in rats at doses lower than maternally toxic doses. When pregnancy is detected, discontinue olmesartan medoxomil tablets as soon as possible. Consider alternative antihypertensive therapy during pregnancy. The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Clinical Considerations Disease-Associated Maternal and/or Embryo/Fetal Risk Hypertension in pregnancy increases the maternal risk for pre-eclampsia, gestational diabetes, premature delivery, and delivery complications (e.g., need for cesarean section and post-partum hemorrhage). Hypertension increases the fetal risk for intrauterine growth restriction and intrauterine death. Pregnant women with hypertension should be carefully monitored and managed accordingly. Fetal/Neonatal Adverse Reactions Oligohydramnios in pregnant women who use drugs affecting the renin-angiotensin system in the second and third trimesters of pregnancy can result in the following: reduced fetal renal function leading to anuria and renal failure, fetal lung hypoplasia, skeletal deformations, including skull hypoplasia, hypotension and death. […]
If too much is taken
Limited data are available related to overdosage in humans. The most likely manifestations of overdosage would be hypotension and tachycardia; bradycardia could be encountered if parasympathetic (vagal) stimulation occurs. If symptomatic hypotension occurs, initiate supportive treatment. The dialyzability of olmesartan is unknown.
Storing it safely
Storage Store at 20 to 25°C (68 to 77°F) [see USP Controlled Room Temperature].
Before you take anything new
Tell your pharmacist or doctor about every medicine you take — including ones bought without a prescription, herbal products and supplements. Interactions are one of the most common avoidable causes of harm from medicines, and a pharmacist can check your full list in a couple of minutes.
This page is built from the openFDA record of the U.S. Food and Drug Administration's approved labelling for this product, effective 20 January 2026. Label text has been shortened and reformatted for readability; safety wording has not been altered in meaning. FDA labelling describes products approved in the United States — brand names, strengths, formulations and approved uses may differ in your country. Always read the leaflet that comes with your own pack. PocketsInfo is not affiliated with, and is not endorsed by, the FDA. Retrieved 2026-07-30.