Myonit Insta 500mcg Sublingual Tablet

Myonit Insta 500mcg Sublingual Tablet contains Nitroglycerin (glyceryl trinitrate) 500mcg and is presented as a tablet. It is supplied in a pack size of 30s.

It is classified as a non-prescription medicine, so no prescription is needed to order it. Under Malaysian rules for medicine information, this page carries product, safety and handling information only.

You can consult a doctor or pharmacist online on DoctorOnCall about this product before or after you order. Every order is checked by a registered pharmacist before it is delivered. Always read the label and the leaflet supplied with the pack.

Use only as directed by your doctor. At the first sign of angina, sit down (to reduce the risk of dizziness or fainting) and place one tablet under the tongue, allowing it to dissolve completely without chewing or swallowing it; avoid eating, drinking, or smoking while the tablet is dissolving. If chest pain persists after 5 minutes, and your doctor’s plan allows it, a second tablet may be used, followed by a third after another 5 minutes if needed; if pain is not relieved after 3 doses or persists beyond 15 minutes in total, seek emergency medical help immediately, as this may indicate a heart attack rather than ordinary angina.

The usual dose is one 500mcg tablet placed under the tongue at the onset of angina symptoms or a few minutes before an activity known to trigger an attack, repeated after 5 minutes if pain continues, up to a maximum as specifically instructed by your doctor (commonly not more than 3 tablets within 15 minutes). This medicine is for acute relief or short-term prevention of individual angina episodes and is not intended to be taken on a fixed daily schedule; always follow your doctor’s specific instructions for your situation.

Nitroglycerin tablets are sensitive to air, light, and moisture and can lose potency over time, even before the printed expiry date, especially once the container has been opened repeatedly. Follow your pharmacist’s guidance on replacing your supply periodically (commonly every few months once opened) so that it remains effective in an emergency.

Store in the original glass container with the cap tightly closed, away from light, heat, and moisture, at room temperature (do not store in the bathroom or a humid area). Do not transfer tablets to a different container such as a plastic pillbox, as this can reduce potency. Keep out of reach and sight of children, and carry it with you if your doctor has advised you to keep it available for emergency use.

• Known hypersensitivity to nitroglycerin or other nitrates
• Use of medicines for erectile dysfunction such as sildenafil, tadalafil, or vardenafil within the timeframe specified by your doctor, as the combination can cause a dangerous, severe drop in blood pressure
• Severe anaemia, as nitrates can worsen oxygen delivery in this condition
• Increased pressure within the skull (such as after a head injury) or certain types of cardiomyopathy, where your doctor will assess suitability carefully
• Severe low blood pressure or uncorrected low blood volume, until stabilised

• Phosphodiesterase type 5 (PDE5) inhibitor medicines used for erectile dysfunction or pulmonary hypertension must not be combined with nitroglycerin due to the risk of severe, dangerous low blood pressure; always disclose use of these medicines to your doctor
• Alcohol can increase the blood-pressure-lowering and dizziness-inducing effects of nitroglycerin, so caution is advised
• Other blood pressure medicines, including other vasodilators, may add to the blood-pressure-lowering effect and require careful monitoring by your doctor
• Inform your doctor of all prescription, over-the-counter, and herbal products you take, as several classes of medicine can interact with nitrates

• Always sit down before and while using this tablet to reduce the risk of dizziness or fainting
• Carry your tablets with you at all times if your doctor has prescribed this for emergency angina relief, and know your personal maximum-dose instructions
• Never combine this medicine with erectile dysfunction medicines without your doctor’s explicit clearance, due to the risk of dangerous blood pressure drops
• Seek emergency medical care immediately if chest pain is not relieved after your doctor’s specified number of doses, or if pain is severe, spreads to the arm/jaw, or is accompanied by breathlessness, sweating, or nausea — this may be a heart attack, not ordinary angina
• Replace your supply as advised by your pharmacist, since these tablets lose potency over time once opened
• Keep a record of when and how often you use this medicine and share it with your doctor at follow-up visits

Myonit Insta is intended for the rapid relief of angina attacks or short-term prevention before a known trigger, and is typically prescribed as part of a broader heart-health management plan that may include other regular heart medicines, lifestyle changes, and monitoring by a cardiologist or your treating doctor. Because chest pain can have serious causes beyond stable angina, including heart attack, it is essential to follow your doctor’s specific instructions on when to use this medicine, how many doses to take, and — critically — when to stop relying on it and seek emergency care instead. Never delay calling for emergency help because you are waiting to see if another dose of this medicine will work; chest pain that does not resolve as expected needs urgent assessment.