What Is GTN (Glyceryl Trinitrate)?
GTN (glyceryl trinitrate) is a medication that belongs to the nitrate class of drugs. It is widely used in Australia for the treatment of:
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Angina pectoris (chest pain)
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Pulmonary edema
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Congestive heart failure
GTN works by dilating blood vessels, reducing cardiac workload, and improving blood flow.
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GTN Strengths Available in Australia
GTN is available in Australia in different formulations and strengths, including:
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Sublingual tablets – 300 mcg or 600 mcg
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Sublingual spray – 400 mcg per dose
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Transdermal patches – 5 mg to 15 mg per 24 hr
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Ointment – 0.2% to 0.4%
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Ampoules – 50 mg/10 mL (IV use in hospitals)
These forms allow flexibility in treating both acute and chronic conditions.
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The sublingual tablets and spray are used for immediate relief of symptoms, while the patch and ointment are used for long-term prevention. The ampoule is used for intravenous infusion in hospital settings.
The dose and frequency of GTN or nitrates depend on some factors. Such as the condition being treated, the patient’s response, and the doctor’s advice. It is important to follow the instructions on how to use GTN correctly. It can cause side effects such as hypotension, headache, flushing, and bradycardia, So, follow the instructions of use.
Side Effects of GTN (Nitrates)
Like all medications, it may cause side effects. The most common include:
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Headache (very common, due to vasodilation)
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Flushing and facial redness
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Dizziness or fainting (especially when standing up quickly)
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Low blood pressure (hypotension)
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Burning or tingling under the tongue (with sublingual forms)
Precautions
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Do not use with phosphodiesterase-5 inhibitors (e.g., sildenafil) due to severe risk of hypotension.
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Caution in patients with severe anemia, hypotension, or increased intracranial pressure.
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Always use under medical supervision.
Conclusion
GTN (glyceryl trinitrate) is an essential nitrate drug in Australia for managing angina, heart failure, and pulmonary edema. With multiple dosage forms available, it offers flexible treatment options but must be used with caution due to its vasodilatory effects and common side effects like headaches and dizziness.
