Glyceryl trinitrate (GTN)

Nitrate·Cardiovascular - Antiarrhythmics & Antianginals

Acute angina, angina prophylaxis, acute pulmonary oedema, heart failure

PBSNITRATENitrolingual, Lycinate, Transiderm-Nitro, MinitranSublingual pump spray (400 m…S4+1

Max Dose

Variable

Half-life

1–4 mins

Headache

COMMON

Tolerance

HIGH RISK

Rapid Summary

Overview

Potent, extremely fast-acting venodilator. The absolute gold standard for acute termination of angina and reduction of preload in acute pulmonary oedema (APO).

Maximum Dose

Max varies entirely by formulation and BP response. Sublingual: Max 2 sprays/tablets per 15 mins.

Clinical Focus

Causes profound, sudden hypotension. Patients MUST sit down before using the spray.

Bottom Line

Glyceryl trinitrate (GTN) is the first-line sublingual treatment for acute angina and chest pain, but causes significant headache and hypotension, and must never be combined with PDE5 inhibitors.

Formulation & Access

Brand Names

Nitrolingual, Lycinate, Transiderm-Nitro, Minitran

Routes

Sublingual pump spray (400 mcg/dose). SL tablets (600 mcg). Transdermal patches. IV ampoules.

Prescribing & PBS

Spray/Tabs are Pharmacy Medicine (S3). Patches/IV are S4.

Indications & Use

Primary

PBSTGA

Acute angina, angina prophylaxis, acute pulmonary oedema, heart failure.

Clinical Place

First-line for acute cardiac ischaemic chest pain. Powerful preload reducer in the ED/ICU for APO.

Quick reference

Class & Role

Nitrate — Potent, extremely fast-acting venodilator.

Route / Formulation

Sublingual pump spray (400 mcg/dose). SL tablets (600 mcg). Transdermal patches. IV ampoules. (Nitrolingual, Lycinate, Transiderm-Nitro, Minitran)

Usual Dose & Max

SL 300-600 mcg (1/2 to 1 tablet) OR 1-2 sprays under tongue. Wait 5 mins. If pain persists, call ambulance. Max 3 doses/15 mins.

Key Indication Doses

Acute Angina (Sublingual): SL 300-600 mcg (1/2 to 1 tablet) OR 1-2 sprays under tongue. Wait 5 mins. If pain persists, call ambulance. Max 3 doses/15 mins. Angina Prophylaxis (Patch): Apply 5-10 mg patch Topical daily. Remove patch for 10-12 hours overnight to prevent tolerance. Acute Pulmonary Oedema / HTN Crisis: IV Infusion start at 5-10 mcg/min. Titrate rapidly up to 200 mcg/min based on response.

Best Uses

Glyceryl trinitrate (GTN) is the first-line sublingual treatment for acute angina and chest pain, but causes significant headache and hypotension, and must never be combined with PDE5 inhibitors.

Avoid / Cautions

SBP < 90 mmHg, Right Ventricular (Inferior) MI (preload dependent), severe aortic stenosis, raised intracranial pressure. Pregnancy Category B2.

Key Risks

Cardiovascular: Severe orthostatic hypotension, reflex tachycardia, syncope. Neurological: 'Nitrate Headache' (throbbing, severe, caused by meningeal vasodilation). Other: Nitrate tolerance (loss of efficacy if used continuously without a break).

Key Interactions

PDE-5 Inhibitors (Sildenafil/Viagra). Co-administration within 24 hours causes catastrophic, refractory, and fatal hypotension. Check before giving in ED. Alcohol, other antihypertensives (additive drops in BP).

Monitoring

Ensure patient is sitting. Monitor BP and HR continuously if giving IV or repeatedly for angina.

Clinical Pearl

Never give GTN to a patient with an Inferior STEMI (Right Ventricular involvement). The RV requires high preload to push blood into the lungs. GTN removes preload and drops cardiac output to zero.

Access

Nitrolingual, Lycinate, Transiderm-Nitro, Minitran

Brand: Nitrolingual, Lycinate, Transiderm-Nitro, Minitran

Glyceryl trinitrate (GTN)

Nitrate·Cardiovascular - Antiarrhythmics & Antianginals

Acute angina, angina prophylaxis, acute pulmonary oedema, heart failure

PBSNITRATENitrolingual, Lycinate, Transiderm-Nitro, MinitranSublingual pump spray (400 m…S4+1

Max Dose

Variable

Half-life

1–4 mins

Headache

COMMON

Tolerance

HIGH RISK

Rapid Summary

Overview

Potent, extremely fast-acting venodilator. The absolute gold standard for acute termination of angina and reduction of preload in acute pulmonary oedema (APO).

Maximum Dose

Max varies entirely by formulation and BP response. Sublingual: Max 2 sprays/tablets per 15 mins.

Clinical Focus

Causes profound, sudden hypotension. Patients MUST sit down before using the spray.

Bottom Line

Glyceryl trinitrate (GTN) is the first-line sublingual treatment for acute angina and chest pain, but causes significant headache and hypotension, and must never be combined with PDE5 inhibitors.

Formulation & Access

Brand Names

Nitrolingual, Lycinate, Transiderm-Nitro, Minitran

Routes

Sublingual pump spray (400 mcg/dose). SL tablets (600 mcg). Transdermal patches. IV ampoules.

Prescribing & PBS

Spray/Tabs are Pharmacy Medicine (S3). Patches/IV are S4.

Indications & Use

Primary

PBSTGA

Acute angina, angina prophylaxis, acute pulmonary oedema, heart failure.

Clinical Place

First-line for acute cardiac ischaemic chest pain. Powerful preload reducer in the ED/ICU for APO.

Quick reference

Class & Role

Nitrate — Potent, extremely fast-acting venodilator.

Route / Formulation

Sublingual pump spray (400 mcg/dose). SL tablets (600 mcg). Transdermal patches. IV ampoules. (Nitrolingual, Lycinate, Transiderm-Nitro, Minitran)

Usual Dose & Max

SL 300-600 mcg (1/2 to 1 tablet) OR 1-2 sprays under tongue. Wait 5 mins. If pain persists, call ambulance. Max 3 doses/15 mins.

Key Indication Doses

Best Uses

Glyceryl trinitrate (GTN) is the first-line sublingual treatment for acute angina and chest pain, but causes significant headache and hypotension, and must never be combined with PDE5 inhibitors.

Avoid / Cautions

SBP < 90 mmHg, Right Ventricular (Inferior) MI (preload dependent), severe aortic stenosis, raised intracranial pressure. Pregnancy Category B2.

Key Risks

Key Interactions

Monitoring

Ensure patient is sitting. Monitor BP and HR continuously if giving IV or repeatedly for angina.

Clinical Pearl

Never give GTN to a patient with an Inferior STEMI (Right Ventricular involvement). The RV requires high preload to push blood into the lungs. GTN removes preload and drops cardiac output to zero.

Access

Nitrolingual, Lycinate, Transiderm-Nitro, Minitran

Brand: Nitrolingual, Lycinate, Transiderm-Nitro, Minitran