Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
AZOR vs ALDOCLOR-150
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Amlodipine is a dihydropyridine calcium channel blocker that inhibits calcium ion influx across cardiac and vascular smooth muscle cells, causing vasodilation and reduced peripheral vascular resistance. Olmesartan is an angiotensin II receptor blocker (ARB) that selectively blocks AT1 receptors, inhibiting vasoconstriction and aldosterone secretion.
Aldoclor-150 is a combination of methyldopa and chlorothiazide. Methyldopa is a centrally acting alpha-2 adrenergic agonist that reduces sympathetic outflow, decreasing peripheral vascular resistance and blood pressure. Chlorothiazide is a thiazide diuretic that inhibits sodium reabsorption in the distal convoluted tubule, leading to increased excretion of sodium and water, reducing plasma volume and blood pressure.
Treatment of hypertension, alone or with other antihypertensive agents
Hypertension
AZOR is a combination of amlodipine and olmesartan. Typical adult dose: one tablet orally once daily. Available strengths: amlodipine/olmesartan 5mg/20mg, 5mg/40mg, 10mg/20mg, 10mg/40mg. Dose can be titrated based on blood pressure response.
ALDOCLOR-150 is a combination product containing 150 mcg of clonidine and 25 mg of chlorthalidone. The typical adult dose is one tablet orally once daily.
Amlodipine: 30-50 h (terminal); supports once-daily dosing. Olmesartan: 10-15 h (terminal); once-daily dosing effective
Terminal elimination half-life is approximately 6-8 hours in patients with normal renal function. In patients with creatinine clearance <30 m L/min, half-life may be prolonged to 15-20 hours, necessitating dose adjustment.
Amlodipine is extensively metabolized in the liver via CYP3A4 to inactive metabolites. Olmesartan is metabolized by the liver to a minor extent; it undergoes glucuronidation and some oxidation by CYP2C9.
Methyldopa is metabolized primarily via conjugation and decarboxylation; chlorothiazide is not extensively metabolized and is excreted unchanged in urine.
Renal: 90% (amlodipine: 60% as metabolites, 10% as parent; olmesartan: 35-50% as parent via urine, rest in feces via bile). Fecal: 10%
Renal excretion of unchanged drug accounts for approximately 50-60% of the administered dose; hepatic metabolism contributes the remainder, with metabolites excreted via bile and feces. Less than 2% is excreted unchanged in feces.
Amlodipine: ~93% bound to plasma proteins. Olmesartan: >99% bound to albumin
Approximately 70-80% bound to plasma proteins, primarily albumin.
Amlodipine: 21 L/kg (large, extensive tissue distribution). Olmesartan: 17-30 L (approximate, Vd not typically reported per kg); distribution into tissues
Vd is approximately 0.3-0.5 L/kg, indicating distribution primarily in extracellular fluid and limited tissue binding.
Oral: amlodipine 64-90% (high, first-pass ~10%); olmesartan 26% (oral, complete absorption reduced by first-pass ester hydrolysis)
Oral bioavailability is approximately 70-80%; food does not significantly alter absorption.
No dose adjustment is required for mild to moderate renal impairment (Cr Cl ≥30 m L/min). For severe renal impairment (Cr Cl <30 m L/min), use with caution; maximum dose of olmesartan is 20 mg once daily. Monitor serum potassium and creatinine.
Contraindicated in patients with GFR <30 m L/min. For GFR 30-50 m L/min, reduce frequency to every other day. For GFR >50 m L/min, no adjustment necessary.
No dose adjustment for mild hepatic impairment (Child-Pugh A). For moderate to severe hepatic impairment (Child-Pugh B or C), amlodipine half-life is prolonged; initiate with amlodipine 2.5 mg and olmesartan 10 mg, and titrate slowly. Use caution; contraindicated in severe hepatic impairment with cholestasis? Not specifically contraindicated but not recommended.
Child-Pugh Class A: No adjustment necessary. Child-Pugh Class B: Reduce dose by 50% or extend dosing interval. Child-Pugh Class C: Use is not recommended due to risk of hepatic encephalopathy and fluid retention.
Safety and efficacy in pediatric patients <18 years have not been established. Not recommended for use in children.
Not recommended for pediatric use due to lack of safety and efficacy data in patients under 18 years of age.
In elderly patients (≥65 years), start with the lowest available dose (amlodipine/olmesartan 5/20 mg daily) and titrate slowly due to increased sensitivity and potential for hypotension. Monitor renal function and electrolytes closely in geriatric patients.
Initiate at lower dose (e.g., half tablet) due to increased sensitivity to antihypertensive effects, risk of orthostatic hypotension, and impaired renal function. Monitor blood pressure and electrolytes closely.
None
None.
Fetal toxicity (detectable in second and third trimesters): drugs acting on the renin-angiotensin system can cause oligohydramnios, fetal renal dysfunction, and death,Avoid concomitant use with aliskiren in patients with diabetes,Hypotension in volume/depleted patients,Increased angina or myocardial infarction with calcium channel blockers, particularly with severe obstructive coronary artery disease,Peripheral edema is dose-dependent and more common with amlodipine,Hepatic impairment: lower starting dose,Renal artery stenosis,Electrolyte imbalances
May cause sedation, dizziness, and orthostatic hypotension. Avoid abrupt discontinuation. Use with caution in patients with impaired renal function, liver disease, or history of depression. Monitor for electrolyte imbalance, especially hypokalemia, due to chlorothiazide component.,Methyldopa may cause positive direct Coombs test, hemolytic anemia, and liver disorders. Discontinue if jaundice or liver abnormalities occur.
Hypersensitivity to any component,Do not use with aliskiren in patients with diabetes
Hypersensitivity to methyldopa, chlorothiazide, or sulfonamide-derived drugs.,Active liver disease or previous methyldopa-induced liver disorders.,Anuria or severe renal impairment (creatinine clearance <30 m L/min).
Avoid grapefruit and grapefruit juice due to CYP3A4 inhibition increasing amlodipine levels. No other significant food interactions.
Avoid excessive potassium-rich foods (bananas, oranges, spinach) unless directed, as thiazide can cause potassium loss; however, monitor for hypokalemia. Limit sodium intake to enhance antihypertensive effect. Methyldopa absorption is not significantly affected by food.
Pregnancy Category D. First trimester: Potential for fetal toxicity (oligohydramnios, fetal/neonatal renal dysfunction, skull hypoplasia) due to olmesartan action on renin-angiotensin system; avoid use. Second trimester: Continued risk of fetal renal impairment and oligohydramnios. Third trimester: High risk of fetal/neonatal renal failure, hypotension, hyperkalemia, and skull ossification defects; contraindicated.
First trimester: Increased risk of neural tube defects (spina bifida) and other major congenital malformations (e.g., cardiovascular, orofacial clefts) due to folate antagonism. Second and third trimesters: Risk of intrauterine growth restriction (IUGR), oligohydramnios, and renal dysplasia. Neonatal: Folate deficiency, megaloblastic anemia, and potential for methotrexate-like toxicity if used near term.
No human data on olmesartan or amlodipine excretion in breast milk. Amlodipine transfers into human milk with M/P ratio approximately 0.5-1.5; risk to infant unknown. Due to potential for adverse effects (hypotension, renal impairment), use is not recommended. Alternative antihypertensives with more safety data should be considered.
Pyrimethamine (component of ALDOCLOR-150) is excreted into breast milk in small amounts; the M/P ratio is not well established. Sulfadoxine (component) is also excreted. Theoretical risk of kernicterus in jaundiced infants due to sulfonamide displacement of bilirubin. Use with caution, especially in preterm or G6PD-deficient infants. The benefits of breastfeeding should outweigh potential risks; alternative antimalarials are preferred.
Not applicable; use is contraindicated in pregnancy. No dose adjustment can mitigate fetal risk; alternative agents (e.g., labetalol, nifedipine) are preferred. If inadvertently used, discontinue as soon as pregnancy is detected.
No standard dose adjustment required, but consider increased folic acid supplementation (5 mg daily) to reduce teratogenic risk. Due to increased glomerular filtration rate (GFR) in pregnancy, renal clearance may be enhanced; however, ALDOCLOR-150 is typically used as a single dose and pharmacokinetic data do not support routine dose adjustment. Individualize based on clinical response and toxicity monitoring.
AZOR is a fixed-dose combination of amlodipine (calcium channel blocker) and olmesartan (angiotensin II receptor blocker). Monitor serum potassium and creatinine, especially in renal impairment or concomitant ACE inhibitor use. Avoid in pregnancy (use effective contraception). May cause dizziness or peripheral edema, often dose-related.
ALDOCLOR-150 combines chlorothiazide (a thiazide diuretic) and methyldopa (a central alpha-2 agonist). Monitor for hypokalemia and hyponatremia due to thiazide; methyldopa may cause positive Coombs test (hemolytic anemia risk) and hepatotoxicity. Titrate methyldopa slowly to avoid sedation. Use with caution in renal impairment (Cr Cl <30 m L/min reduces thiazide efficacy).
Take exactly as prescribed, usually once daily, with or without food.,Avoid grapefruit or grapefruit juice as it can increase amlodipine levels.,Notify your doctor if you become pregnant or plan to become pregnant.,Do not stop taking suddenly; consult your doctor before discontinuing.,Report lightheadedness, fainting, or significant swelling in your ankles or feet.,Use caution when driving or operating machinery until you know how this medication affects you.
Take medication exactly as prescribed, usually once or twice daily.,May cause dizziness or drowsiness; avoid driving until effects are known.,Stand up slowly to prevent falls from low blood pressure.,Report unexplained fever, fatigue, or jaundice (signs of liver issues).,Avoid alcohol, which enhances sedative effects.,Do not stop abruptly (risk of rebound hypertension).
No interactions on record
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about AZOR vs ALDOCLOR-150, answered by our medical review team.
AZOR is a Antihypertensive Combination that works by Amlodipine is a dihydropyridine calcium channel blocker that inhibits calcium ion influx across cardiac and vascular smooth muscle cells, causing vasodilation and reduced peripheral vascular resistance. Olmesartan is an angiotensin II receptor blocker (ARB) that selectively blocks AT1 receptors, inhibiting vasoconstriction and aldosterone secretion.. ALDOCLOR-150 is a Antihypertensive Combination (Central Alpha Agonist and Thiazide Diuretic) that works by Aldoclor-150 is a combination of methyldopa and chlorothiazide. Methyldopa is a centrally acting alpha-2 adrenergic agonist that reduces sympathetic outflow, decreasing peripheral vascular resistance and blood pressure. Chlorothiazide is a thiazide diuretic that inhibits sodium reabsorption in the distal convoluted tubule, leading to increased excretion of sodium and water, reducing plasma volume and blood pressure.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between AZOR and ALDOCLOR-150 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 AZOR is: AZOR is a combination of amlodipine and olmesartan. Typical adult dose: one tablet orally once daily. Available strengths: amlodipine/olmesartan 5mg/20mg, 5mg/40mg, 10mg/20mg, 10mg/40mg. Dose can be titrated based on blood pressure response.. The standard adult dose of ALDOCLOR-150 is: ALDOCLOR-150 is a combination product containing 150 mcg of clonidine and 25 mg of chlorthalidone. The typical adult dose is one tablet orally once daily.. 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 AZOR and ALDOCLOR-150 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. AZOR is classified as Category C. Pregnancy Category D. First trimester: Potential for fetal toxicity (oligohydramnios, fetal/neonatal renal dysfunction, skull hypoplasia) due to olmesartan action on renin-angioten. ALDOCLOR-150 is classified as Category C. First trimester: Increased risk of neural tube defects (spina bifida) and other major congenital malformations (e.g., cardiovascular, orofacial clefts) due to folate antagonism. Se. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.