Istin

What is Istin?

Istin is one of the brand names of a drug called amlodipine. It’s a prescription only medication that’s used to treat two common conditions – angina and high blood pressure.

Angina is a pain that starts in your chest and sometimes spreads elsewhere. It’s caused by reduced blood flow to your heart muscles, and while it isn’t usually life-threatening, it is a warning sign that you could be at risk of experiencing a heart attack or a stroke.^[1]
The pain of angina can vary from a tightness that makes it feel hard to breathe, to a dull, heavy discomfort that spreads to your arms, shoulders, back or jaw. An angina attack is usually brought on by stress or physical activity, and stops within a few minutes of resting.

High blood pressure, also known as hypertension, is when the force of the blood pumping through your arteries is too high. The more that your heart pumps and the narrower your arteries, the higher your blood pressure will be. People who have an unhealthy lifestyle are more likely to develop high blood pressure. This includes those who are overweight, eat too much salt, fat and sugar, smoke, or drink too much alcohol. Stress is also a big factor in high blood pressure. If you have high blood pressure, it can make angina symptoms worse. High blood pressure also increases your risk of serious health problems including heart disease, stroke and a heart attack.^[2]

How does Istin work?

The active ingredient in Istin, amlodipine, is what’s known as a ‘calcium channel blocker’. Calcium channel blockers work by causing the muscle cells in your artery walls to relax. This enables your arteries to widen, letting blood flow through them more easily. This means that the heart doesn’t have to work as hard to push blood around the body, reducing blood pressure to a healthy level. Having a lower blood pressure reduces your risk of a number of health problems, including angina.

What doses of Istin are there?

Istin is available in two doses:

• 5mg
• 10mg

The dose that you’ll be prescribed will be based on your personal circumstances, such as your age, how high your blood pressure is, and if you have any other health conditions (such as any issues with your liver or kidneys). But typically you’ll start on the lower dose of 5mg and be monitored – with the dosage being increased if the starting dose isn’t working well enough. You might have to stay on the lower dose if you have some underlying conditions or you’re struggling with side effects.

How to take Istin

Istin can be taken with or without food, and should be taken orally, once per day. It can be helpful to take it at the same time every day so that it becomes routine, making you less likely to forget a dose.

Istin tablets should always be swallowed whole with water. However if you struggle to swallow tablets, you can dissolve the tablet in a glass of water first, so long as you drink the whole glass immediately afterwards.

You shouldn’t eat or drink lots of grapefruit or grapefruit juice when you’re taking Istin tablets. This is because grapefruit can increase the concentration of Istin in your body, making side effects more likely.

How long does it take Istin to work?

Istin starts to work immediately, but it may take several weeks for your blood pressure to reach its lowest levels. Because high blood pressure rarely causes any noticeable symptoms, you probably won’t realise that your blood pressure has come down unless you get it checked. If you suffer from angina, your symptoms and the frequency of your angina attacks should start to reduce within a few weeks. ^[1]

What should I do if I make a mistake when taking Istin?

Always take Istin exactly as you’ve been told to by our clinician.

If you accidentally take more Istin than you should, you should seek medical help straight away, and don’t drive. Excessive levels of amlodipine can cause drowsiness, which makes driving dangerous. Make sure you take your Istin packaging with you, along with any remaining medication.

If you have missed a dose of Istin, you should take it as soon as you remember. However, if it’s nearly time for your next dose, you should skip the missed dose and continue as normal. Never take more Istin to ‘catch-up’ on the dose that you missed.