Anril® SR (Nitroglycerin 2.6 mg Sustained-Release) - Product Monograph

For angina prophylaxis

Indications

• Prophylaxis of chronic angina pectoris

  Not indicated for acute anginal attacks (onset too slow).
  (Use under registered physician's guidance)

Pharmacology

Mechanism of Action

• Potent vasodilator acting on venous and arterial smooth muscle:

  • Venodilation → ↓ Venous return → ↓ Preload

  • Arteriodilation → ↓ Systemic vascular resistance → ↓ Afterload

• Net effect: Reduced myocardial oxygen demand.

Dosage & Administration

Adults

• Standard: 2.6 mg SR tablet twice daily (morning & evening).

• Critical Administration Guidelines:

  • Take 1 hour before or 2 hours after meals (fasting state optimizes absorption).

  • Do not crush/chew (sustained-release formulation).

• Titration: Adjust based on angina frequency/tolerance (↓ dose if persistent headache).
  (Follow registered physician's advice)

Interactions

Contraindications

• Hypersensitivity to nitrates

• Concomitant PDE5 inhibitors

• Acute MI • Severe anemia • Closed-angle glaucoma

• Head trauma/hemorrhage • Cardiogenic shock

Side Effects

Common (>10%):

• Headache (transient; dose-dependent)

• Orthostatic hypotension • Reflex tachycardia

Serious:

• Methemoglobinemia (cyanosis) • Syncope

Pregnancy & Lactation

• Pregnancy: Use only if benefit justifies risk (limited safety data).

• Lactation: Avoid (excretion unknown).

Precautions & Warnings

1. Glaucoma Risk: Screen for narrow-angle glaucoma.

2. Withdrawal Protocol: Taper gradually to avoid rebound angina.

3. Acute MI: Avoid in early infarction (↑ hypotension/tachycardia risk).

4. Hemodynamic Monitoring: Essential in cardiac compromise.

5. Orthostatic Caution: Rise slowly from sitting/lying position.

Overdose Management

Symptoms:

• Severe hypotension • Tachycardia • Weakness

Treatment:

1. Immediate: Trendelenburg position + IV fluids.

2. Refractory Cases:

   • Norepinephrine infusion (avoid epinephrine!)

   • Oxygen + methylene blue for methemoglobinemia.

3. Monitor ECG + BP for 24h.

Therapeutic Class

Organic Nitrate Vasodilator

Storage

• Conditions: 15–30°C • Protect from light/moisture

• Stability: Degrades rapidly if exposed to heat/air

• Keep out of children's reach