Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
TECZEM vs ALDORIL D30
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Enalapril inhibits angiotensin-converting enzyme (ACE), reducing angiotensin II formation, leading to vasodilation and decreased aldosterone secretion. Diltiazem inhibits calcium ion influx across cardiac and smooth muscle cells, causing coronary vasodilation and decreased myocardial contractility.
Aldoril D30 is a combination of methyldopa, a centrally acting alpha-2 adrenergic agonist that reduces sympathetic outflow, and hydrochlorothiazide, a thiazide diuretic that inhibits the sodium-chloride symporter in the distal convoluted tubule, decreasing plasma volume and peripheral resistance.
Hypertension,Stable angina,Chronic stable angina
Hypertension
1 to 2 tablets (enalapril 5 mg/diltiazem 180 mg) orally once daily. Maximum: 2 tablets daily.
Oral: 1 tablet (hydrochlorothiazide 30 mg / methyldopa 500 mg) twice daily; maximum dose: 2 tablets twice daily.
Terminal elimination half-life: 3-4 hours for diltiazem; clinical context: requires twice-daily dosing due to short half-life.
Terminal elimination half-life of hydrochlorothiazide is 6-15 hours; methyldopa half-life is 1.8 hours (normal renal function). In renal impairment, half-life of both components is prolonged.
Enalapril is hydrolyzed to active enalaprilat, mainly hepatically. Diltiazem is extensively metabolized in the liver via CYP3A4.
Methyldopa is metabolized by conjugation (catechol-O-methyltransferase) and hepatic sulfation; hydrochlorothiazide is not extensively metabolized and is excreted unchanged by the kidney.
Renal: 40-50% unchanged; hepatic/biliary/fecal: 50-60% as metabolites.
Renal: approximately 50% as parent drug and metabolites; biliary/fecal: minimal, less than 5%.
70-80% bound to albumin and alpha-1-acid glycoprotein.
Methyldopa: <10% bound to plasma proteins; hydrochlorothiazide: 40-68% bound to albumin.
5-7 L/kg; indicates extensive tissue distribution.
Methyldopa: Vd 0.2-0.3 L/kg (distributes into tissues, crosses placenta); hydrochlorothiazide: Vd 0.75-1.5 L/kg (extensively distributed, does not cross blood-brain barrier significantly).
Oral: 35-60% due to first-pass metabolism; IV: 100%.
Oral bioavailability of methyldopa is approximately 25% (variable, influenced by gut metabolism); hydrochlorothiazide bioavailability is 65-75%.
GFR >30 m L/min: No adjustment. GFR 10-30 m L/min: Use with caution, monitor potassium and creatinine. GFR <10 m L/min: Avoid use.
GFR 30-60 m L/min: reduce dose by 50%; GFR <30 m L/min: not recommended.
Child-Pugh A: No adjustment. Child-Pugh B: Use with caution, consider starting at lowest dose. Child-Pugh C: Contraindicated.
Child-Pugh Class B or C: contraindicated; use not recommended.
Safety and efficacy not established for patients <18 years.
Not recommended for use in pediatric patients due to lack of safety and efficacy data.
Start at lowest dose, monitor renal function and electrolytes due to age-related decreased renal function and increased sensitivity.
Start with lowest dose; monitor for hypotension, electrolyte imbalance, and CNS effects; consider reduced initial dose.
Use in pregnancy: ACE inhibitors can cause injury and death to the developing fetus. Discontinue as soon as possible when pregnancy is detected.
None
Hypotension,Angioedema,Hepatic injury,Heart block,Bradycardia,Renal impairment,Hyperkalemia
May cause hemolytic anemia, liver disorders, positive Coombs test, sedation, depression, and hypersensitivity reactions. Hydrochlorothiazide may cause electrolyte imbalance, hyperuricemia, photosensitivity, and exacerbation of systemic lupus erythematosus. Use with caution in renal impairment, hepatic disease, and in patients with a history of drug-induced hemolytic anemia.
Hypersensitivity to enalapril, diltiazem, or any component,History of angioedema related to ACE inhibitors,Second- or third-degree AV block (except with pacemaker),Sick sinus syndrome,Severe hypotension,Cardiogenic shock,Concurrent use with riociguat
Active hepatic disease, history of previous methyldopa therapy-associated liver disorders; anuria; hypersensitivity to methyldopa, hydrochlorothiazide, or sulfonamide-derived drugs.
Avoid high-potassium foods (e.g., bananas, oranges, spinach) due to potential for hyperkalemia from enalapril. Grapefruit juice may increase diltiazem levels and should be limited or avoided. Alcohol can exacerbate hypotension.
Food may decrease absorption of methyldopa. Avoid excessive intake of high-potassium foods (e.g., bananas, oranges) unless directed. Hydrochlorothiazide may cause potassium depletion; maintain adequate dietary potassium. Avoid natural licorice as it can worsen hypokalemia.
TECZEM (enalapril maleate and felodipine) is contraindicated in pregnancy. ACE inhibitors can cause fetal and neonatal morbidity and death when administered to pregnant women. First trimester exposure may be associated with a small increased risk of congenital anomalies; second and third trimester exposure is associated with oligohydramnios, fetal renal dysfunction, skull ossification defects, and neonatal hypotension, anuria, and renal failure. Felodipine: No teratogenic effects in animal studies at clinically relevant doses; however, limited human data. Combined use should be avoided in pregnancy.
First trimester: Limited data; no clear evidence of major malformations but methyldopa crosses placenta. Second and third trimesters: Associated with reduced placental perfusion; possible fetal bradycardia and neonatal hypotension. Hydrochlorothiazide may cause fetal/neonatal jaundice, thrombocytopenia, and electrolyte disturbances.
Enalapril is excreted in human milk in trace amounts; the M/P ratio is approximately 0.01. Felodipine is excreted in human milk; the M/P ratio is unknown. Due to potential for adverse effects in the nursing infant, especially renal effects from enalapril, breastfeeding is not recommended during TECZEM therapy.
Methyldopa is excreted in breast milk in low concentrations; M/P ratio approximately 0.2. Hydrochlorothiazide is excreted in minimal amounts; may suppress lactation. Consider risks versus benefits.
TECZEM is contraindicated in pregnancy. If a woman becomes pregnant while on TECZEM, discontinue the drug immediately. No dose adjustments are recommended as the drug should not be used. Alternative antihypertensive therapy should be considered if needed.
Methyldopa: Pregnancy-induced plasma volume expansion may require dose titration; monitor blood pressure and adjust accordingly. Hydrochlorothiazide: Often avoided in pregnancy due to volume depletion risks; if used, monitor electrolytes and renal function, no pharmacokinetic data necessitate routine dose adjustment.
TECZEM (enalapril/diltiazem ER) combines an ACE inhibitor and a non-dihydropyridine calcium channel blocker. Monitor renal function and serum potassium; avoid in patients with pre-existing high-grade AV block or severe left ventricular dysfunction. Use with caution in patients with hepatic impairment due to diltiazem metabolism. May cause reflex tachycardia less frequently than dihydropyridines.
ALDORIL D30 combines methyldopa (central alpha-2 agonist) and hydrochlorothiazide (thiazide diuretic). Monitor for orthostatic hypotension, especially at initiation. Taper not needed for methyldopa but discontinue if fever or liver dysfunction occurs. Interferes with urinary catecholamine measurements (false elevation). Hydrochlorothiazide may cause hyponatremia, hypokalemia, and hyperglycemia; check electrolytes and glucose periodically.
Take this medication exactly as prescribed; do not crush or chew the extended-release tablet.,Monitor blood pressure regularly and report symptoms such as dizziness, fainting, or irregular heartbeat.,Avoid salt substitutes containing potassium unless directed by your doctor.,Report any signs of angioedema (swelling of face, lips, tongue, or difficulty breathing) immediately.
Take exactly as prescribed, preferably with food to reduce stomach upset.,Rise slowly from sitting or lying down to prevent dizziness.,This drug may make you drowsy; avoid driving or operating machinery until you know how it affects you.,Report fever, unexplained fatigue, jaundice, or dark urine immediately.,Weigh yourself daily and report rapid weight gain or swelling.,Limit alcohol intake as it can increase side effects.,Do not use salt substitutes containing potassium without consulting your doctor.
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 TECZEM vs ALDORIL D30, answered by our medical review team.
TECZEM is a Antihypertensive combination that works by Enalapril inhibits angiotensin-converting enzyme (ACE), reducing angiotensin II formation, leading to vasodilation and decreased aldosterone secretion. Diltiazem inhibits calcium ion influx across cardiac and smooth muscle cells, causing coronary vasodilation and decreased myocardial contractility.. ALDORIL D30 is a Antihypertensive Combination that works by Aldoril D30 is a combination of methyldopa, a centrally acting alpha-2 adrenergic agonist that reduces sympathetic outflow, and hydrochlorothiazide, a thiazide diuretic that inhibits the sodium-chloride symporter in the distal convoluted tubule, decreasing plasma volume and peripheral resistance.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between TECZEM and ALDORIL D30 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 TECZEM is: 1 to 2 tablets (enalapril 5 mg/diltiazem 180 mg) orally once daily. Maximum: 2 tablets daily.. The standard adult dose of ALDORIL D30 is: Oral: 1 tablet (hydrochlorothiazide 30 mg / methyldopa 500 mg) twice daily; maximum dose: 2 tablets twice 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 TECZEM and ALDORIL D30 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. TECZEM is classified as Category C. TECZEM (enalapril maleate and felodipine) is contraindicated in pregnancy. ACE inhibitors can cause fetal and neonatal morbidity and death when administered to pregnant women. Firs. ALDORIL D30 is classified as Category C. First trimester: Limited data; no clear evidence of major malformations but methyldopa crosses placenta. Second and third trimesters: Associated with reduced placental perfusion; p. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.