Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
DEMI-REGROTON 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
DEMI-REGROTON is a fixed-dose combination of chlorothiazide (a thiazide diuretic) and reserpine (a Rauwolfia alkaloid). Chlorothiazide inhibits the Na+-Cl- symporter in the distal convoluted tubule, reducing sodium and water reabsorption. Reserpine depletes catecholamines (norepinephrine, dopamine, serotonin) from central and peripheral nerve endings by inhibiting vesicular monoamine transporter 2 (VMAT2), leading to reduced sympathetic outflow and vasodilation.
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.
Hypertension (adjunctive therapy)
Hypertension
One tablet orally once daily, each tablet containing 25 mg chlorthalidone and 0.125 mg reserpine.
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.
Terminal elimination half-life is 40-60 hours (mean 48 h), allowing once-daily dosing; steady state reached in 5-7 days
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.
Chlorothiazide: Not extensively metabolized; excreted unchanged in urine. Reserpine: Extensively metabolized in the liver via hydrolysis and glucuronidation; active metabolites.
Methyldopa is metabolized primarily via conjugation and decarboxylation; chlorothiazide is not extensively metabolized and is excreted unchanged in urine.
Renal: 70% as unchanged drug; biliary/fecal: 30% as metabolites
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.
90% bound to albumin and alpha-1-acid glycoprotein
Approximately 70-80% bound to plasma proteins, primarily albumin.
3-5 L/kg, indicating extensive extravascular distribution
Vd is approximately 0.3-0.5 L/kg, indicating distribution primarily in extracellular fluid and limited tissue binding.
Oral: 65-75% due to first-pass metabolism
Oral bioavailability is approximately 70-80%; food does not significantly alter absorption.
Contraindicated if GFR <30 m L/min. For GFR 30-60 m L/min, reduce dose to half tablet daily and monitor electrolytes. No adjustment needed if GFR >60 m L/min.
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.
Contraindicated in severe hepatic impairment (Child-Pugh class C). For Child-Pugh class B, use half the initial dose and titrate cautiously. No adjustment for Child-Pugh class A.
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.
Not recommended for pediatric use due to safety and efficacy data lacking. No established pediatric dosing guidelines.
Not recommended for pediatric use due to lack of safety and efficacy data in patients under 18 years of age.
Initiate at half tablet (12.5 mg chlorthalidone/0.0625 mg reserpine) daily. Monitor for orthostatic hypotension, electrolyte imbalance, and CNS depression. Titrate slowly based on response and tolerability.
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.
Reserpine: Risk of mental depression and suicidal tendencies. Treatment should be discontinued at the first sign of depression.
None.
Hypotension, electrolyte imbalance (especially hypokalemia), depression (with reserpine), peptic ulcer disease (reserpine may increase gastric acid secretion), and sensitivity reactions (chlorothiazide, sulfonamide derivative).
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 chlorothiazide, reserpine, or sulfonamides; anuria; history of depression (especially with suicidal tendencies); active peptic ulcer; ulcerative colitis; concurrent electroconvulsive therapy (ECT).
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 excessive potassium intake (bananas, oranges, salt substitutes) due to risk of hyperkalemia from chlorthalidone. Limit sodium to enhance antihypertensive effect. Grapefruit juice may alter drug metabolism; avoid large quantities.
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.
FDA Pregnancy Category C. First trimester: potential risk of neural tube defects and cardiovascular anomalies based on animal studies; human data limited. Second and third trimesters: risk of fetal growth restriction, oligohydramnios, and neonatal hypotension due to renin-angiotensin system interference. Avoid in pregnancy unless no alternative.
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.
Excreted in breast milk in low amounts; M/P ratio not established. Potential for adverse effects in nursing infant such as hypotension. Use caution; consider alternative agent.
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.
No specific dose adjustment recommended; use lowest effective dose if necessary. Monitor closely for maternal hypotension and fetal effects.
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.
DEMI-REGROTON (chlorthalidone 15 mg + reserpine 0.125 mg) is indicated for hypertension. Monitor for hypokalemia and hyperuricemia. Reserpine may cause depression; avoid in patients with history of depressive disorders. Chlorthalidone may exacerbate gout. Use cautiously in renal impairment.
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; do not double doses if missed.,May cause dizziness or drowsiness; avoid driving until effects known.,Report symptoms of depression, slow heart rate, or unusual bleeding.,Avoid alcohol and NSAIDs (ibuprofen, naproxen) unless approved by doctor.,Monitor for signs of low potassium: muscle cramps, weakness, irregular heartbeat.,Rise slowly from sitting or lying to prevent dizziness.
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 DEMI-REGROTON vs ALDOCLOR-150, answered by our medical review team.
DEMI-REGROTON is a Antihypertensive Combination that works by DEMI-REGROTON is a fixed-dose combination of chlorothiazide (a thiazide diuretic) and reserpine (a Rauwolfia alkaloid). Chlorothiazide inhibits the Na+-Cl- symporter in the distal convoluted tubule, reducing sodium and water reabsorption. Reserpine depletes catecholamines (norepinephrine, dopamine, serotonin) from central and peripheral nerve endings by inhibiting vesicular monoamine transporter 2 (VMAT2), leading to reduced sympathetic outflow and vasodilation.. 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 DEMI-REGROTON 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 DEMI-REGROTON is: One tablet orally once daily, each tablet containing 25 mg chlorthalidone and 0.125 mg reserpine.. 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 DEMI-REGROTON 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. DEMI-REGROTON is classified as Category C. FDA Pregnancy Category C. First trimester: potential risk of neural tube defects and cardiovascular anomalies based on animal studies; human data limited. Second and third trimeste. 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.