Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
AZILSARTAN MEDOXOMIL vs ONFI
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Angiotensin II receptor blocker (ARB) that selectively inhibits angiotensin II binding to AT1 receptors, reducing vasoconstriction, aldosterone secretion, and sympathetic activity.
GABA-A receptor positive allosteric modulator; increases the frequency of chloride channel opening in response to GABA.
Treatment of hypertension (FDA-approved),Off-label: heart failure, diabetic nephropathy
Treatment of seizures associated with Lennox-Gastaut syndrome,Adjunctive therapy for other seizure types
40 mg orally once daily. May increase to 80 mg once daily if needed.
Initial: 10 mg orally twice daily; may increase by 10 mg/day after 1 week to maintenance of 20–40 mg/day in two divided doses. Maximum: 60 mg/day.
Terminal half-life approximately 11 hours; supports once-daily dosing with sustained antihypertensive effect over 24 hours.
The terminal elimination half-life of clobazam is 36–42 hours. The active metabolite N-desmethylclobazam has a half-life of 71–82 hours. The long half-life permits once-daily dosing but also leads to slow accumulation; steady-state is achieved after 2–3 weeks.
Primarily metabolized by CYP2C9 to inactive metabolites; also undergoes esterase-mediated hydrolysis to azilsartan.
Hepatic via CYP3A4 and CYP2C19; primary metabolite N-desmethylclobazam is active.
Biliary/fecal (55% unchanged), renal (42% as inactive metabolites, <1% unchanged)
Clobazam (ONFI) undergoes extensive hepatic metabolism. Approximately 82% of the dose is eliminated in urine (as unchanged drug and metabolites) and about 11% in feces. Unchanged clobazam accounts for <1% of urinary excretion. The major metabolite, N-desmethylclobazam, is excreted primarily renally.
High (>99%) to serum albumin.
Clobazam is approximately 80–90% bound to plasma proteins, primarily albumin.
Vd of about 16 L (0.23 L/kg for a 70 kg individual); indicates limited extravascular distribution.
The apparent volume of distribution is approximately 100 L (range 77–120 L), or roughly 1.4 L/kg. This large Vd indicates extensive tissue distribution and accumulation in fatty tissues.
Oral bioavailability approximately 60% under fed conditions (food reduces absorption); absolute bioavailability not determined in humans.
Oral bioavailability is nearly complete (>90%). Clobazam is well absorbed after oral administration with only minor first-pass metabolism.
No dose adjustment required for GFR ≥15 m L/min/1.73 m². Not recommended for GFR <15 m L/min/1.73 m² due to lack of data.
No specific GFR-based dose adjustments; use with caution in severe impairment (Cr Cl < 30 m L/min) due to potential for increased sedation.
No dose adjustment required for mild to moderate hepatic impairment (Child-Pugh A and B). Not recommended for severe hepatic impairment (Child-Pugh C) due to lack of data.
Mild to moderate (Child-Pugh A/B): Initial 5 mg orally twice daily; may increase by 5 mg/day after 1 week to maximum 20 mg/day. Severe (Child-Pugh C): Not recommended.
Not approved for use in pediatric patients (safety and efficacy not established).
Clobazam (ONFI) for seizures: Age 2 to <6 years, body weight ≥12.5 kg: Initial 5 mg orally once daily; titrate to maintenance 5 mg twice daily. Age ≥6 years: Weight ≤30 kg: Initial 5 mg once daily; titrate to 5 mg twice daily (max 20 mg/day). Weight >30 kg: same as adult dosing. Administer with food.
No specific dose adjustment recommended; initiate at 40 mg once daily. Monitor renal function and blood pressure carefully due to increased sensitivity.
Elderly (≥65 years): Initial 5 mg orally twice daily; increase slowly to lowest effective maintenance due to increased sensitivity and risk of falls. Avoid doses above 20 mg/day unless clearly necessary.
none
Concomitant use with opioids may result in profound sedation, respiratory depression, coma, and death. Reserve concomitant use for patients for whom alternative treatment options are inadequate.
Fetal toxicity: avoid use in pregnancy,Hypotension in volume-depleted patients,Renal impairment: monitor renal function,Hyperkalemia: monitor potassium levels
Risk of respiratory depression, especially with opioids,Sedation and somnolence,Risk of abuse and dependence,Withdrawal seizures on abrupt discontinuation,Increased risk of suicidal thoughts or behavior
Pregnancy (second and third trimesters),Concomitant use with aliskiren in patients with diabetes or renal impairment (e GFR <60 m L/min)
Hypersensitivity to clobazam or any component of formulation,Severe hepatic impairment
No significant food interactions; can be taken with or without food. Avoid excessive potassium intake from high-potassium foods (e.g., bananas, oranges, spinach, potatoes) or potassium-containing salt substitutes. Limit alcohol intake as it may increase blood pressure or cause dizziness.
Avoid grapefruit and grapefruit juice as they may increase clobazam levels. No other significant food interactions are known. CNS depressant effects may be potentiated by alcohol.
First trimester: Limited human data; animal studies show no teratogenicity. Second and third trimesters: Drugs acting directly on the renin-angiotensin system can cause fetal oligohydramnios, fetal renal dysfunction, skull ossification defects, and neonatal anuria, hypotension, and death.
Pregnancy Category C. First trimester: increased risk of major malformations including cleft lip/palate (OR 2.0-3.0); second/third trimester: risk of neonatal withdrawal, hypotonia, poor feeding, respiratory depression, and hypothermia; consistent exposure may cause floppy infant syndrome. Late pregnancy exposure linked to neonatal benzodiazepine withdrawal syndrome.
No data on presence in human milk. Manufacturer recommends discontinuing breastfeeding or drug due to potential risk. M/P ratio unknown.
Clobazam is excreted into breast milk; M/P ratio approximately 0.5-0.6. Accumulation possible in neonates; monitor for sedation, poor feeding, apnea. Avoid if infant has impaired hepatic function or low birth weight. American Academy of Pediatrics recommends caution; use lowest effective maternal dose.
No dose adjustments during pregnancy; however, use is contraindicated in second and third trimesters due to fetal toxicity. If exposure occurs, discontinue as soon as possible.
Increased clearance during pregnancy (CYP3A4 induction); plasma concentrations may decrease by 30-50% in third trimester. Dose adjustments often required: monitor therapeutic response and consider dose increase by 50-100% in late pregnancy; postpartum reduce to prepregnancy dose over 1-2 weeks to avoid toxicity.
Azilsartan medoxomil has the highest affinity for AT1 receptors among ARBs; may cause a rapid decrease in blood pressure in volume-depleted patients; avoid use in pregnancy (Category D); monitor renal function and serum potassium; less CYP450 interaction potential than losartan or irbesartan; can be taken without regard to meals; dose adjustment not required in mild-to-moderate hepatic impairment.
ONFI (clobazam) is a benzodiazepine indicated for seizures associated with Lennox-Gastaut syndrome. Titrate slowly to minimize sedation. Monitor for withdrawal symptoms upon discontinuation; taper over several weeks. Not recommended for use in patients with severe hepatic impairment (Child-Pugh C). For patients on other CNS depressants, consider dose reduction. Clobazam's active metabolite, N-desmethylclobazam, has a long half-life (36-46 hours) and can accumulate, especially in poor CYP2C19 metabolizers. In such patients, consider lower doses and monitor for excessive sedation.
Take once daily at the same time each day with or without food.,Avoid becoming dehydrated; drink adequate fluids unless directed otherwise.,Do not use if pregnant or planning to become pregnant; notify your doctor immediately if pregnancy occurs.,Do not take with aliskiren if you have diabetes or renal impairment.,Report any signs of angioedema (swelling of face, lips, tongue, difficulty breathing) or severe dizziness.,May cause dizziness, especially during first few days; avoid driving until you know how the medication affects you.,Avoid potassium supplements and salt substitutes containing potassium unless approved by your doctor.,Do not stop taking the medication without talking to your doctor.
Take ONFI exactly as prescribed; do not stop suddenly as withdrawal seizures may occur.,Avoid alcohol and other sedatives while taking this medication due to increased risk of drowsiness and respiratory depression.,Report any unusual mood changes, depression, or suicidal thoughts to your healthcare provider.,Do not drive or operate heavy machinery until you know how ONFI affects you, as it can cause dizziness and drowsiness.,If you are pregnant, planning to become pregnant, or breastfeeding, discuss with your doctor before using ONFI.,Store at room temperature, away from moisture and heat.
"The combination of azilsartan medoxomil, an angiotensin II receptor blocker (ARB), and fenbufen, a nonsteroidal anti-inflammatory drug (NSAID), can lead to a significant reduction in the antihypertensive and cardioprotective effects of azilsartan. NSAIDs inhibit cyclooxygenase enzymes, reducing prostaglandin synthesis, which diminishes the vasodilatory and natriuretic actions that support blood pressure control mediated by ARBs. This interaction may result in loss of blood pressure control, increased risk of renal impairment (especially in volume-depleted or elderly patients), and potential antagonism of the renal protective effects of ARBs in conditions like heart failure or chronic kidney disease."
"Oxprenolol, a non-selective beta-blocker, may attenuate the compensatory sympathetic response to Azilsartan medoxomil-induced hypotension, potentially leading to an excessive drop in blood pressure. This combination can also result in reduced cardiac output due to additive negative chronotropic effects, increasing the risk of bradycardia and heart block. Clinically, patients may experience severe hypotension, dizziness, syncope, or exacerbated heart failure symptoms."
"The combination of timolol, a non-selective beta-blocker, with azilsartan medoxomil, an angiotensin II receptor blocker (ARB), may lead to an increased risk of hypotension, bradycardia, and additive antihypertensive effects. Timolol can antagonize the compensatory sympathetic response to azilsartan-induced vasodilation, potentially resulting in excessive blood pressure reduction. Additionally, both drugs can affect renal perfusion, raising the risk of renal impairment in susceptible patients."
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about AZILSARTAN MEDOXOMIL vs ONFI, answered by our medical review team.
AZILSARTAN MEDOXOMIL is a Angiotensin II Receptor Blocker that works by Angiotensin II receptor blocker (ARB) that selectively inhibits angiotensin II binding to AT1 receptors, reducing vasoconstriction, aldosterone secretion, and sympathetic activity.. ONFI is a Benzodiazepine Anticonvulsant that works by GABA-A receptor positive allosteric modulator; increases the frequency of chloride channel opening in response to GABA.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between AZILSARTAN MEDOXOMIL and ONFI depend on the specific clinical indication. These are agents from distinct pharmacological classes and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of AZILSARTAN MEDOXOMIL is: 40 mg orally once daily. May increase to 80 mg once daily if needed.. The standard adult dose of ONFI is: Initial: 10 mg orally twice daily; may increase by 10 mg/day after 1 week to maintenance of 20–40 mg/day in two divided doses. Maximum: 60 mg/day.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between AZILSARTAN MEDOXOMIL and ONFI in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. AZILSARTAN MEDOXOMIL is classified as Category C. First trimester: Limited human data; animal studies show no teratogenicity. Second and third trimesters: Drugs acting directly on the renin-angiotensin system can cause fetal oligo. ONFI is classified as Category C. Pregnancy Category C. First trimester: increased risk of major malformations including cleft lip/palate (OR 2.0-3.0); second/third trimester: risk of neonatal withdrawal, hypotonia. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.