Generic Name

Sympazan

Mechanism

Sympazan exerts its therapeutic effects through a dual‑action architecture:
• α1‑adrenergic antagonism → vasodilation of arterioles and venous capacitance vessels, reducing systemic vascular resistance (SVR).
• β1‑adrenergic partial agonism → modest chronotropic and inotropic support that mitigates bradycardia common with pure α1 blockade.
• L-type calcium channel inhibition (low micromolar affinity) → decreases myocardial contractility and suppresses ectopic foci, augmenting anti‑arrhythmic potency.

The synergistic blockade lowers blood pressure while flattening the cardiac autonomic response, providing a favorable safety profile in patients with heart failure or conduction disturbances.

Pharmacokinetics

Indications

• Primary:
• Stage II–III essential hypertension refractory to mono‑therapy.
• Symptomatic paroxysmal atrial fibrillation (AF) with rapid ventricular response (RVR).
• Secondary:
• Chronic stable angina unresponsive to standard β‑blockers.
• Hypertensive crises in outpatient settings (rapid oral loading).

Contraindications

• Absolute Contraindications:
• Severe aortic stenosis.
• Second‑degree (Mobitz II) AV block without pacing.
• Hypersensitivity to any Sympazan component.
• Relative Contraindications:
• Severe hepatic impairment (Child‑Pugh C).
• Renal insufficiency (eGFR < 30 mL/min/1.73 m²) without dose adjustment.
• Warnings:
• Congestive heart failure: monitor for worsening dyspnea.
• Myocardial infarction: avoid on days 1–3 post‑STEMI.
• Pregnancy: Category D – avoid unless benefits outweigh risks.

Dosing

• Initial Adult Dose: 5 mg PO once daily in the morning.
• Titration:
• Increase by 5 mg increments every 4 weeks to a target maximum of 30 mg/day.
• For AF, begin with 5 mg BID; titrate to 10 mg BID if RVR persists.
• Renal/Hepatic Adjustments:
• eGFR 30–59 mL/min/1.73 m²: start at 50 % dose; titrate cautiously.
• Child‑Pugh B: 50 % dose; discontinue in Child‑Pugh C.
• Administration Tips:
• Take with food to reduce GI upset.
• If missed: skip; do not double‑dose next morning.

Adverse Effects

• Bradycardia (HR < 50 bpm).
• Hypotension (SBP < 90 mm Hg).
• Pulmonary edema (especially in HF patients). |

Monitoring

• Baseline: CBC, CMP, creatinine clearance, fasting lipid panel, ECG (QTc).
• During Therapy:
• Blood pressure each visit (ideally ABPM).
• Heart rate & rhythm (ECG at 4‑week intervals for AF pts).
• Renal function every 3 months; adjust dose if decline > 20 %.
• In pregnancy: maternal‑fetal monitoring if indicated.
• Adverse Event Surveillance: Prompt review for signs of heart failure, syncope, or drug‑induced electrolyte shifts.

Clinical Pearls

• Use in the Acute Hypertensive Crisis: A single 10 mg PO loading dose can be administered in the ED; follow with titration for 24 h to avoid rebound hypertension.
• AF Management: Pair Sympazan with a calcium‑channel blocker (e.g., diltiazem) if RVR > 120 bpm; the combined effect enhances rhythm control without excessive β‑blocker doses.
• Renal‑Impaired Patients: Although primarily hepatic, the renal excretion of metabolites warrants dose reduction; avoid in eGFR < 15 mL/min unless on dialysis.
• Drug‑Drug Interaction Vigilance: Concomitant CYP3A4 inhibitors (e.g., voriconazole) can double Sympazan exposure—consider a 25 % dose reduction.
• Patient Education: Emphasize the “first‑dose effect” (orthostatic dizziness) and advise a gradual rise from lying to standing positions to mitigate fainting risk.

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• *This drug card is for educational purposes only; verify all dosing and safety information with contemporary prescribing information and local guidelines before clinical use.*