Isordil (Isosorbide Dinitrate) Uses in Pakistan

Isordil (Isosorbide Dinitrate — ISDN) is prescribed in Pakistan for angina pectoris. This guide covers all its uses, mechanism of action, and important warnings.

Compiled by the PakVita Editorial Team · AI-assisted drafting with editorial review · Sourced from DRAP, WHO, BNF · Last updated: 2026-06-17

Uses

Quick Answer

Isordil (Isosorbide Dinitrate) is used in Pakistan for angina pectoris prophylaxis, sublingual relief of acute anginal attacks, and as adjunct therapy in left ventricular failure. It is a nitrate — it relaxes blood vessels and reduces the load on the heart. Rx medicine — do not take without a doctor.

Primary Uses at a Glance

Angina Pectoris Prophylaxis

Isosorbide Dinitrate on regular oral dosing reduces myocardial oxygen demand through venodilation (preload reduction) and mild arterial dilation (afterload reduction) — reducing the frequency and severity of anginal episodes. Multiple daily doses with a nitrate-free interval are required.

On doctor's prescription — asymmetric dosing.

Acute Angina Relief — Sublingual

Placing a 5mg sublingual tablet under the tongue releases nitric oxide within 2-5 minutes and rapid vasodilation provides relief from anginal pain. GTN/nitroglycerin spray is more commonly used for acute angina but ISDN sublingual is also effective.

When an angina attack occurs — immediately place the sublingual tablet under the tongue; if no relief in 5 minutes take a 2nd dose; if still no relief after 3 doses (15 min) — IMMEDIATE EMERGENCY.

Left Ventricular Failure (Adjunct)

In heart failure venodilation reduces preload and provides relief from breathlessness. Used as adjunct therapy — only on cardiologist's advice.

On specialist / cardiologist prescription only.

Oesophageal Spasm (Off-Label)

The smooth muscle relaxation mechanism can also provide pain relief in oesophageal spasm. Off-label use — only on gastroenterologist's advice.

Off-label — specialist guidance required.

Other Uses

Left ventricular failure (adjunct)

Isordil (Isosorbide Dinitrate) Uses (Fayde / Kis kaam aata hai)

Isordil contains Isosorbide Dinitrate (ISDN) — it belongs to the Nitrate group of medicines. Below are all its approved and common uses in Pakistan.

Primary Uses (Mukhya Istemal)

Angina Pectoris Prophylaxis — prevention of heart pain through regular oral dosing
Acute Angina Relief — sublingual 5mg tablet — under the tongue — effect within 2-5 minutes
Left Ventricular Failure (Adjunct) — venodilation reduces preload, relief from breathlessness
Oesophageal Spasm (Off-Label) — smooth muscle relaxation mechanism — specialist guidance required

How Isosorbide Dinitrate Works (Kaise Kaam Karta Hai)

ISDN metabolizes in the body and releases nitric oxide (NO) → activates guanylate cyclase → cGMP increases → smooth muscle relaxes → venodilation (preload reduction) + mild arterial dilation (afterload reduction) → myocardial oxygen demand decreases → angina is prevented or relieved.

Nitrate Tolerance — Critical Warning

If isordil is taken multiple times daily at the same time, nitrate tolerance develops — effectiveness decreases. The solution: overnight nitrate-free interval (10-12 hours) — asymmetric dosing. Strictly follow your doctor's dosing schedule.

Who Should Take It

Adults with diagnosed stable angina pectoris under cardiologist care
Patients requiring acute anginal relief (sublingual)
Heart failure patients under specialist supervision
NOT for patients on PDE5 inhibitors (sildenafil/tadalafil/vardenafil)

When NOT to Use

Patients taking PDE5 inhibitors (sildenafil/Viagra, tadalafil/Cialis, vardenafil) — ABSOLUTELY CONTRAINDICATED — fatal hypotension
Riociguat — CONTRAINDICATED
Severe hypotension / hypovolemia
Known nitrate allergy

Summary

Isordil (ISDN) is an effective nitrate for angina. NEVER take with PDE5 inhibitors (Viagra-type medicines). Maintaining the nitrate-free interval prevents tolerance. Only on doctor's prescription.

The information in this guide is for educational purposes only.

Frequently Asked Questions

Isordil / ISDN kis cheez ke liye use hoti hai?

Isordil (Isosorbide Dinitrate) is used for the prevention and acute relief of angina pectoris. It is an Rx medicine of the nitrate class — do not take without a doctor.

Isordil sublingual kab use karte hain?

The sublingual 5mg tablet is placed under the tongue when an angina attack occurs. It should take effect within 2-5 minutes. If there is no effect after 3 doses, seek IMMEDIATE EMERGENCY care.

Kya isordil sirf angina ke liye hai?

Primary use is angina prophylaxis and acute relief. It is also used as an adjunct in left ventricular failure. Off-label use in oesophageal spasm also exists. Only on doctor's advice.

Isordil aur GTN mein kya farq hai (uses mein)?

Both are nitrates and effective for angina. GTN (glyceryl trinitrate) sublingual spray/tablet is most commonly used for acute angina — faster-acting. ISDN sublingual also provides acute relief. ISMN (mononitrate) is often preferred for prophylaxis.

Kya isordil heart attack treatment karta hai?

No — isordil is for angina PREVENTION and relief. In a heart attack (myocardial infarction) seek emergency help immediately — isordil alone does not treat a heart attack.

Brand alternatives, same-class options, and other medicines used for the same conditions as Isordil Tablet.

Used for the same conditions

Other medicines commonly used for stomach pain (abdominal pain) and overlapping conditions.

Stomach Pain (Abdominal Pain) hub →

Sources

DRAP Registered Products Database — Drug Regulatory Authority of Pakistan
WHO Model List of Essential Medicines, 23rd ed. (2023) — World Health Organization
British National Formulary (BNF) — BMJ Group & Pharmaceutical Press

Medical disclaimer

This page is for educational use only and does not replace professional medical advice. Always confirm diagnosis, dose, and interactions with a qualified doctor or pharmacist before starting or changing any medicine.