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Antihypertensive Combination/Discontinued

SERPASIL-APRESOLINE

SERPASIL-APRESOLINE

Clinical safety rating

caution

Comprehensive clinical and safety monograph for SERPASIL-APRESOLINE (SERPASIL-APRESOLINE).


Mechanism of Action

Combination of reserpine (depletes catecholamines from sympathetic nerve endings) and hydralazine (direct vasodilator, increases cGMP via NO).

What the body does with it

MetabolismReserpine: hydrolyzed in gut, metabolites excreted in urine. Hydralazine: N-acetylation via NAT2.
ExcretionReserpine: <1% unchanged in urine; extensive hepatic metabolism followed by renal and fecal excretion. Hydralazine: 80-90% renal; 10% fecal; 1-2% unchanged in urine; polymorphic acetylation (rapid/slow acetylators) affects clearance.
Half-lifeReserpine: ~50-100 hours (biphasic; terminal phase 4.5-11 days due to enterohepatic circulation and tissue binding). Hydralazine: 2-8 hours (rapid acetylators 30-50 min, slow acetylators 2-8 hours); longer in renal impairment.
Protein bindingReserpine: ~96% (bound to albumin and α1-acid glycoprotein). Hydralazine: 85-90% (primarily albumin; also binds to α1-acid glycoprotein and lipoproteins).
Volume of DistributionReserpine: ~8-10 L/kg (extensive tissue binding, especially adipose and brain). Hydralazine: 1.5-8 L/kg (increases with hypertension; reflects high tissue distribution).
BioavailabilityReserpine: 5-30% oral (extensive first-pass metabolism; variable). Hydralazine: 30-50% oral (slow acetylators have higher bioavailability due to reduced first-pass acetylation; rapid acetylators 10-30%).
Onset of ActionReserpine: 3-6 hours oral, up to 1 week for full effect. Hydralazine: 20-30 minutes oral; 5-20 minutes intramuscular; immediate intravenous (5-15 min for peak effect).
Duration of ActionReserpine: 6-24 hours single dose; cumulative effect with repeated dosing; persistent autonomic effects due to irreversible vesicular monoamine transporter binding. Hydralazine: 2-6 hours oral; 2-4 hours parenteral; hypotensive effect may last up to 12 hours in slow acetylators.
Molecular WeightReserpine: 608.68 Da; Hydralazine: 160.18 Da (as base); 196.23 Da (as hydrochloride salt)

Classification & Brands

Dosing & administration

1 tablet (containing reserpine 0.1 mg and hydralazine 25 mg) orally once daily; may increase to twice daily if needed. Maximum dose: 2 tablets per day.

Dosage formTABLET
Renal impairmentGFR <30 mL/min: Use with caution; reduce hydralazine component by 50%. GFR 30-50 mL/min: No adjustment needed for hydralazine; reserpine use contraindicated if severe renal impairment.
Liver impairmentChild-Pugh A: No adjustment. Child-Pugh B: Reduce hydralazine dose by 50%. Child-Pugh C: Contraindicated due to risk of encephalopathy from reserpine and hepatotoxicity.
Pediatric useWeight-based: 0.01 mg/kg reserpine and 2.5 mg/kg hydralazine per day orally, divided into 1-2 doses. Maximum: reserpine 0.25 mg/day, hydralazine 50 mg/day.
Geriatric useStart at half the adult dose (1 tablet every other day) due to increased sensitivity to hypotension and CNS depression. Monitor for orthostatic hypotension and electrolyte imbalances.

Use during pregnancy

1st trimesterAvoid. Serpasil (reserpine) is associated with increased risk of congenital malformations, including neural tube defects and cardiovascular anomalies. Apresoline (hydralazine) has been associated with fetal harm, including malformations and neonatal complications.
2nd trimesterAvoid. Both components carry risks: reserpine may cause neonatal respiratory depression, bradycardia, and hypothermia; hydralazine may cause fetal distress and neonatal lupus-like syndrome.
3rd trimesterAvoid. Reserpine can cause severe neonatal effects such as respiratory depression, bradycardia, and hypothermia. Hydralazine may induce maternal hypotension, leading to reduced placental perfusion and fetal distress.

Clinical note

Comprehensive clinical and safety monograph for SERPASIL-APRESOLINE (SERPASIL-APRESOLINE).

Placental transferBoth reserpine and hydralazine cross the placenta. Reserpine shows significant transfer, with fetal plasma levels similar to maternal levels. Hydralazine crosses the placenta and can achieve therapeutic concentrations in the fetus.
BreastfeedingReserpine is excreted into breast milk and may cause adverse effects in nursing infants, including respiratory depression, bradycardia, and gastrointestinal disturbances. Hydralazine is present in low levels in breast milk, but limited data suggest potential for hypotension and other cardiovascular effects. Due to the risks, breastfeeding is not recommended during therapy with Serpasil-Apresoline.
Lactation RatingL5 - Avoid
Teratogenic RiskFirst trimester: Limited data; beta-blockers (reserpine component) associated with fetal bradycardia and growth restriction. Second/third trimester: Hydralazine and reserpine may cause neonatal hypotension, bradycardia, and hypothermia. Reserpine may increase risk of neonatal respiratory depression and nasal congestion.
Fetal MonitoringMaternal: Blood pressure, heart rate, electrolyte levels, liver function, renal function, and signs of hypotension or fluid retention. Fetal: Serial ultrasound for growth, amniotic fluid volume, and heart rate assessment; nonstress test or biophysical profile in third trimester.
Fertility EffectsReserpine may impair female fertility by altering pituitary-gonadal axis and prolactin levels; hydralazine has no known significant effect on fertility.

Warnings & precautions

■ FDA Black Box Warning

None

Side Effect Profile

Serious Effects

Absolute Contraindications

History of hypersensitivity to reserpine, hydralazine, or any component of the formulationActive peptic ulcer disease (due to reserpine)Ulcerative colitis (due to reserpine)Electroconvulsive therapy (within 2 weeks prior or concurrent; reserpine increases seizure risk)Severe renal impairment (creatinine clearance < 30 mL/min; hydralazine accumulation)Severe hepatic disease (hydralazine metabolism impaired)Systemic lupus erythematosus (hydralazine can induce lupus-like syndrome)Concomitant use with MAOIs (hypertensive crisis risk with reserpine)Pheochromocytoma (reserpine can provoke hypertensive crisis)

Clinical Precautions

PrecautionsReserpine may cause depression, peptic ulcer, or arrhythmias., Hydralazine may cause drug-induced lupus, peripheral neuritis, or orthostatic hypotension., Monitor for hypotension and renal impairment.
Food/DietaryAvoid tyramine-rich foods (aged cheeses, cured meats, fermented products, soy sauce, beer, wine) due to MAO inhibition from reserpine component; however, risk is lower than classical MAOIs. Avoid alcohol. Limit foods high in sodium to prevent fluid retention.

Clinical Tips & Counseling

Clinical PearlsSerpasil-Apresoline is a fixed-dose combination of reserpine and hydralazine, both antihypertensives with complementary mechanisms. Reserpine depletes catecholamines and serotonin, while hydralazine is a direct vasodilator. This combination is rarely used today due to poor tolerability (significant CNS depression, depression risk) and availability of better-tolerated agents. Monitor for orthostatic hypotension, bradycardia, and signs of depression. Avoid in patients with history of depression, peptic ulcer disease, or MAOI use. Abrupt withdrawal can cause hypertensive crisis.
Patient AdviceTake exactly as prescribed; do not skip doses or stop suddenly. · May cause dizziness or lightheadedness; rise slowly from sitting or lying positions. · Avoid alcohol and other central nervous system depressants. · Report any persistent fatigue, mood changes, or signs of depression. · May cause nasal congestion; do not use decongestants without consulting doctor. · Avoid prolonged sun exposure; may increase skin photosensitivity. · Contact doctor if you experience swelling of ankles/feet, weight gain, or shortness of breath. · Store at room temperature away from moisture and light.

SERPASIL-APRESOLINE Interactions

Loading safety data…

This overview is compiled from peer-reviewed clinical sources and FDA labeling. It's here to support — not replace — clinical judgment. Always verify dosing against your institution's current protocols before prescribing.

On this page

Mechanism of ActionDosing & administrationUse during pregnancyWarnings & precautionsDrug interactions

Compare with

ALDOCLOR-150ALDOCLOR-250ALDORIL 15ALDORIL 25ALDORIL D30

External sources

DailyMed (NIH) PubMed OpenFDA