📌 Medicine Name:
Glyceryl Trinitrate Sublingual Tablet 0.5 mg
(Also known as Nitroglycerin sublingual tablet in some regions)
📋 Description / Prescription:
Glyceryl trinitrate (GTN) sublingual tablet is a prescription-only medicine used for the rapid relief and prevention of angina pectoris (chest pain) due to coronary artery disease.
- Each tablet contains 0.5 mg of glyceryl trinitrate
- Administered under the tongue (sublingual) for rapid absorption
🔬 Nature / Mechanism of Action:
- GTN is a nitrate vasodilator
- It is converted to nitric oxide (NO) in the body, which activates guanylate cyclase
- This leads to relaxation of vascular smooth muscle, venodilation, and reduced myocardial oxygen demand
✅ Advantages / Therapeutic Benefits:
- ⚡ Rapid relief of angina symptoms within 1–3 minutes
- 🫀 Reduces preload and afterload on the heart
- ⏱️ Can be used before exertion to prevent angina
- 💊 Compact, fast-acting emergency medicine
- 🚑 Often used in acute coronary syndrome protocols
📦 Packaging:
- Usually packed in airtight amber glass bottles or foil strips to protect from light and moisture
- Each bottle often contains 25 or 100 tablets
- Tablets are small, round, and white, designed to dissolve quickly under the tongue
🌡️ Storage:
- Store at 15–25°C (59–77°F)
- Protect from light, heat, air, and moisture
- Keep in original airtight container—GTN is very unstable and easily degrades
- Discard unused tablets after 8–12 weeks of opening (follow manufacturer’s label)
⚠️ Precautions:
Use with caution in patients with:
- Severe hypotension, shock, or hypovolemia
- Increased intracranial pressure
- Severe anemia
- Closed-angle glaucoma (rare concern)
🚫 Do not use with:
- Phosphodiesterase-5 inhibitors (e.g., sildenafil, tadalafil, vardenafil)—risk of profound hypotension
- Alcohol—may enhance blood pressure-lowering effect
👩⚕️ Patient Advice / Counseling Points:
- 💊 Place one tablet under the tongue and allow it to dissolve—do not chew or swallow
- 🪑 Sit or lie down before taking to avoid dizziness or fainting
- ⏱️ If chest pain persists after 5 minutes, take a second tablet
- Up to 3 tablets can be used at 5-minute intervals
- 🚑 Seek emergency help if pain continues after 3 tablets in 15 minutes
- 🧃 Avoid alcohol
- 🕒 Use before physical or emotional stress if advised
- 🔁 Do not use continuously for long periods—may lead to tolerance
- 💡 Keep tablets in original container, tightly closed
- ❌ Replace bottle after opening, as potency reduces quickly