What is olmesartan (angiotensin II receptor antagonist) medoxomil?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: April 11, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

From the Guidelines

Olmesartan medoxomil is an angiotensin II receptor blocker (ARB) with a target dose of 40 mg, once daily, as recommended by the 2020 ACC/AHA clinical performance and quality measures for adults with heart failure 1. The medication works by relaxing blood vessels, allowing blood to flow more easily and lowering blood pressure.

  • Key points about olmesartan medoxomil include:
    • It is used to treat high blood pressure (hypertension)
    • The typical starting dose is 20 mg once daily, which may be increased to a maximum of 40 mg daily if needed for blood pressure control
    • Olmesartan blocks the action of angiotensin II, a natural substance that narrows blood vessels and causes sodium and water retention, both of which contribute to high blood pressure
    • This medication is usually taken once daily with or without food and may be prescribed alone or in combination with other blood pressure medications like diuretics
    • Common side effects include dizziness, back pain, and upper respiratory infections
    • Patients should be aware that olmesartan should not be taken during pregnancy as it can cause harm to the developing fetus, particularly in the second and third trimesters
    • Regular monitoring of blood pressure and kidney function is important while taking this medication, as recommended by the ACC/AHA guidelines 1.

From the FDA Drug Label

Olmesartan medoxomil, 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]imidazole­-5-carboxylate, cyclic 2,3-carbonate Its molecular formula is C29H30N6O6 and its structural formula is: [Chemical Structure] Olmesartan medoxomil USP is a white to off-white, crystalline powder with a molecular weight of 558. 59.

Olmesartan medoxomil is a prodrug that is hydrolyzed to olmesartan during absorption, and olmesartan is a selective AT1 subtype angiotensin II receptor antagonist. Key characteristics of olmesartan medoxomil include:

  • Molecular formula: C29H30N6O6
  • Molecular weight: 558.59
  • Appearance: White to off-white, crystalline powder 2

From the Research

Definition and Mechanism of Action

  • Olmesartan medoxomil is a new orally active angiotensin II (Ang II) type 1 receptor antagonist 3.
  • It is a prodrug that is rapidly de-esterified during absorption to form olmesartan, the active metabolite 3, 4.
  • Olmesartan is a potent, competitive and selective Ang II type 1 receptor antagonist that inhibits the actions of angiotensin II on the renin-angiotensin-aldosterone system 5, 6.

Pharmacokinetics and Pharmacodynamics

  • Olmesartan medoxomil is rapidly absorbed from the gastrointestinal tract and converted during absorption to olmesartan, which is subsequently excreted without further metabolism 4.
  • Peak plasma concentrations of olmesartan occur 1-3 h after administration, after which concentrations decrease with an elimination half-life of 10-15 h 4.
  • The absolute bioavailability of olmesartan from olmesartan medoxomil tablets is 28.6% 4.

Clinical Efficacy and Safety

  • Olmesartan medoxomil has been shown to be effective in reducing blood pressure in patients with hypertension, with a favorable adverse-event profile 3, 4, 5, 6, 7.
  • It is recommended for the treatment of adult patients with hypertension, with a usual dose of 20 mg once daily, increasing to 40 mg if needed 4, 6.
  • Olmesartan medoxomil has been compared to other antihypertensive agents, including losartan, valsartan, and irbesartan, and has been shown to be at least as effective in reducing blood pressure 3, 6, 7.

Related Questions

What is the maximum recommended dosage of olmesartan (angiotensin II receptor antagonist) for treating hypertension?
What is the maximum recommended dose of olmesartan?
Is it reasonable to reduce olmesartan 20mg to 10mg daily in a patient with hypotension?
Is olmesartan (angiotensin II receptor antagonist) available in 10 mg tablets?
Can the dose of Olmesartan Medoxomil (angiotensin II receptor antagonist) be increased for an elderly female patient with uncontrolled hypertension (blood pressure in the 150s) on a current dose of 20 MG?
What are the treatments for dementia?
What are the clinical practice guidelines for coarctation of the aorta?
What is the most likely explanation for this patient's oliguria, characterized by impaired renal function, given her history of recent fever and bloody diarrhea, and current presentation of fatigue, petechiae, facial swelling, and laboratory results indicating anemia, thrombocytopenia, and elevated serum urea nitrogen and creatinine levels?
What is the priority in managing a 45-year-old woman with a seizure disorder, experiencing daily seizures despite adherence to phenobarbital (phenobarbital) therapy, and recently increased alcohol (ethanol) consumption to two beers daily?
What is the most likely explanation for this patient's oliguria, characterized by impaired renal function, given her history of recent fever and bloody diarrhea, and current presentation of anemia, thrombocytopenia, and hyperkalemia?
What is the clinical significance of elevated Interleukin-18 (IL-18) levels?

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.