What is Hypertension?

Transcription

1 What is Hypertension? What is hypertension? Hypertension is also known as high blood pressure. Our blood needs to be under pressure to make it move around the body, but when it is too high this causes problems. Blood pressure readings come as two numbers and are measured in The first or top number should be the largest. It is the pressure reached in your arteries when your heart contracts, and is called the systolic blood pressure. The second or bottom number it the lowest number and is the pressure in your arteries when the heart is relaxed between beats. It is the diastolic blood pressure. Hypertension is normally classed as a blood pressure over 140/90 mmhg. Hypertension can be treated with both lifestyle changes and, if needed, medication, however, medication may not be started until the blood pressure is over 160/100 mmhg unless you are at high risk of complications such as a stroke. What is the cause? In 90-95% of people we do not know the cause; this is then called essential hypertension. The remaining people have secondary hypertension which means that it is as a result of another condition such as kidney disease. Although we do not know the causes of essential hypertension, we do know what can increase your risk of getting it. Family history: If a close family member such as a parent has hypertension this increases your chance of getting it as well Obesity: Overweight individuals have higher blood pressure than thinner individuals Salt: Salt contains an element called sodium and people who have a lot of sodium in their diet have higher blood pressure than other people. High alcohol intake: Drinking more than the recommended amounts of alcohol per week is linked to high blood pressure, you should try and keep within the recommended limits. Lack of exercise: As well as helping to keep you fit and lose weight, it is thought that exercise also triggers your body to release chemicals which lower your blood pressure. Stress: Feeling stressed or being in pain both increase your blood pressure Ethnicity, being South Asian or African- Caribbean means you have a higher risk Why does it matter? Hypertension is one of the major risk factors of cardiovascular problems such as heart attacks, strokes and can contribute to kidney failure and heart disease as well as other problems. Hypertension often has no symptoms, which can make it dangerous as people do not know that they have it. Most people are diagnosed after a routine check- up at their doctors. What tests are there? Your doctor can measure your blood pressure easily using an inflatable cuff. Most monitors are now automatic, the cuff inflates around the arm and an attached screen will display your readings. This is usually done at least twice during the appointment and the readings will determine what will happen next. To confirm a diagnosis you doctor should ask you to return for two more appointments and at each of these it you blood pressure should be measured twice. Condition Leaflet 4 (Hypertension) Last updated: 4 th February 2013

2 Your doctor will perform some other tests as well after you have been diagnosed with hypertension. These will help assess you risk of getting other complications. A urine test will check for protein and a blood test will look at your blood sugar levels, cholesterol and kidney function. You may be sent for a heart trace to check your heart is working properly, this involves placing sensors on your body which are connected to a computer and will not take long. What is the treatment? Diet and lifestyle Firstly you should try and make changes to your diet and lifestyle. You should do more exercise and try to lose some weight if you are overweight. Diet changes are the most important: Salt: Keep salt intake to less than 6g a day (about 1 teaspoon), also remember that a lot of ready meals will contain salt in them already but cutting down on adding salt to your food can help. Eat health: Eat a healthy balanced diet, try to eat two or three portions of fish each week with one being oily fish such as anchovies or herring. Also eat at least five portions of fruit and vegetables each day. Alcohol: - 4 units of alcohol per day (about 1 ½ pints of 4% larger) and women 2-3 units (a small 175ml glass of 13% wine). You should also try to have at least 2 alcohol free days each week. Exercise: Exercise regularly, a brisk walk or swimming for 30 minutes a day a few times a week (or more if possible) will help to reduce your blood pressure and provide other health benefits. Medication There are several medications that you can take to reduce your blood pressure, you doctor will decide which medicine is best suited for you. Often you may start on a low dose and this will be increased over time until your blood pressure is under control. If using one medicine is not lowering your blood pressure enough to your target then additional medicines may be added in as well. ACE Inhibitors (e.g. Lisinopril or Ramipril): These prevent a chemical being made which normally acts in the body to increase blood pressure. Angiotensin II receptor blockers (e.g. Losartan): Also called ARBs work in the same way as the ACE inhibitors above and can be used if you suffer side effects from these. Calcium channel blockers (e.g Amlodipine or Diltiazem): These can work in two different ways, by relaxing the blood vesicles or by slowing the heart rate. Diuretics (e.g bendroflumethiazide or indapamide): These are sometimes called water tablets. They reduce blood pressure by reducing the removing excess water and decreasing the volume of blood. This increases the amount of urine that you pass so should be taken in the morning to prevent you waking up in the night to go to the toilet or wetting the bed. Beta blockers (e.g. Atenolol or Bisoprolol): These slow the heart rate down which reduces the total output from the heart. They are not the first dug used unless there is a good reason such as another condition which will benefit from the drugs. As hypertension increases your risk of cardiovascular problems you may be put on other medicines to reduce that risk, for example a cholesterol lowering drug like Simvastatin. What do I need to do? The most important thing you can do is to stick to the treatment plan your doctor gives you. Some people whether they take them or not, however it is important to stick to your treatment. Further information: Blood Pressure UK is a charity dedicated to lowering the nation's blood pressure and has lots of helpful information. This site has information on many conditions, type hypertension in the search box to get started. Condition Leaflet 4 (Hypertension) Last updated: 4 th February 2013

3 ACE Inhibitors Lisinopril, Ramipril and Enalapril What is an ACE inhibitor? An ACE inhibitor is a drug which is commonly used to lower blood pressure. They are usually the first choice drug if you are less than 55 years old and are not black. If you are over 55 or black then usually a different drug called a calcium channel blocker is used first. The most commonly used ACE inhibitors used at Beech Hill medical practice are Lisinopril (Zestril ), Ramipril (Tritace ) and enalapril (Innovace ). ACE inhibitor stands for angiotensin converting enzyme inhibitor, what this means is that the drug stops an enzyme in the body making a chemical being made which normally acts to increase our blood pressure. These drugs are also used in patients who have heart failure or other conditions, so if you read about this somewhere else do not be alarmed. Angiotensin I How do I take it? The doses for different ACE inhibitors is not the same, however they all work the same way. They should be taken ONCE daily It does not matter if you take it in the morning or at night, but some people prefer to take it at night at first it as it can make them feel light headed. Whey can be taken with or without food, it does not matter Your dose will start out low at first, and every 2 or 3 weeks this will be slowly increased Ramipril: Starting dose is mg ONCE daily up to a maximum of 10mg daily. Lisinopril: Starting dose is 10mg ONCE daily up to a maximum of 80mg, usually 20mg daily is enough Enalapril: Starting dose is 5mg ONCE daily up to a maximum of 40mg, usually 20mg daily is enough What are the side effects? Step 1 Step 2 Angiotensin II Converted by enzyme Drug acts here All drugs have side effects, but it is important to remember that you will not experience all of these, and the majority of patients do not experience any side effects at all. These side effects are common and happen in 1-10% of patients A dry persistent cough, this is caused by the drug blocking another chemical called bradykinin from being removed. If this happens a lower dose or a different drug can be used. Dizziness Headache Feeling faint when you stand up, sometimes called postural hypotension Diarrhoea Vomiting These side effects are less common and happen about 0.1-1% of patients Mood alterations Tingling sensation Vertigo (dizziness when at hights) Acts on our cells and cause our Blood Pressure to increase. Hypertension Drug Leaflet 1 Last updated: 4 th February 2013

4 Change in taste Sleep disturbances A change in the colour of your figures and toes called Raynaud's phenomenon A runny nose Abdominal pain A rash Hypoglycaemia when taken with anti- diabetic drugs especially if you have reduced kidney function Does it react with my other medicines? ACE inhibitors can interact with some other prescribed medicines; this means that they can affect how they work. Ciclosporin: This is an immunosuppressant drug that can increase your blood levels of potassium, leading to serious heart problems. Diuretics: These help you lose excess water through urine and are given to treat oedema (a build- up of water) and to lower blood pressure. If given with an ACE inhibitor however there is a very large drop in blood pressure that can be dangerous. This IS sometimes used by doctor if your hypertension is not responding to treatment but care must be taken. Potassium sparing diuretics and aldosterone antagonists: These are a types of diuretics but can lead to increased levels of potassium which can be dangerous and cause heart problems. Lithium: This is a drug used in the treatment of manic depressive disorder and its levels in the blood can be affected when taking an ACE inhibitor. Potassium salts: These include those you can buy from shops marketed a low sodium salt and can lead to dangerously high potassium levels which can affect you heart so should be avoided. Sodium Aurothiomalate (Myocrisin ): This is a type of gold used to treat arthritis but can lead to flushing and very low blood pressure. You should always tell anyone who is treating you that you are taking an ACE inhibitor. This also applies to buying over the counter medicines. Is it safe for me? If any of the following apply to you then you should not normally take an ACE inhibitor, or extra care should be taken to closely monitor you while you take it. A history of angioedema (Swelling of the skin due to a build- up of water) Hepatic impairment (Liver damage) Renal impairment as this can increase the chance of side effects and cause further kidney damage Pregnant What happens if I take too many or miss a dose? next dose. If it is almost time for your next dose, then miss this dose and take the next one as usual. If you take too many by mistake then you may experience severe hypotension. Depending on how many you took you may also have electrolyte disturbances, dizziness, anxiety, cough and renal failure, in some cases this can be dangerous so you should seek medical advice immediately. This leaflet only provides an overview of your medicine and aims to provide answers to people most common questions, it is not comprehensive and if you need more detail you should read the leaflet that comes with your medicine or speak to a healthcare professional such as your doctor or a pharmacist. Hypertension Drug Leaflet 1 Last updated: 4 th February 2013

5 Calcium Channel Blockers Amlodipine and Diltiazem What is a calcium channel blocker? A calcium channel blocker is a drug which is commonly used to lower blood pressure. It is usually the first choice drug if you are over 55 or are black. There are two different types of calcium channel blockers, these are in called: dihydropiridines (e.g. amlodipine) and negative inotropes (e.g. diltiazem). Both these types of drugs relax the muscle around your blood vesicles, but negative inotropes also have an effect on your heart. Calcium channel blockers work by stopping calcium from entering the smooth muscle around your blood vesicles causing your muscles to relax, which lowers your blood pressure The most commonly used calcium channel blockers used at Beech Hill medical practice are amlodipine (Istin ) and diltiazem (Tildiem ). They can also be used to treat a heart condition called angina so if you read about this somewhere else do not be alarmed. How do I take it? Amlodipine is a white to off white colour and comes in two strengths 5mg or 10mg. The initial does for high blood pressure is 5mg once daily This may be increased to 10mg once daily if needed It does not matter what time of day you take it but try to take it at the same time each day. You can take it with or without food. Diltiazem can come as tablets or capsules. It is also available as a modified release which means that it will release its dose more slowly. The amount you take will depend of the type you are given. The long acting type come in several brand such as Adizem- SR, Adizem- XL, Tildiem LA, Tildiem Retard and others. What are the side effects? All drugs have side effects, but it is important to remember that you will not experience all of these, and the majority of patients do not experience any side effects at all. These side effects are the common and occur in 1-10% of patients: Drowsiness Fatigue Dizziness Oedema (a build- up of fluid) Headache A condition called AV block (changes to Palpitations the electrical signals in the heart) Flushing Constipation Abdominal pain Nausea Nausea feeling generally unwell These side effects are the less common and occur in 0.1-1% of patients: Insomnia Dry mouth Mood changes Hair loss Tremor Rash Taste and visual disturbances Increase in liver enzymes Vomiting Hypertension Drug Leaflet 2 Last updated: 4 th February 2013

6 These side effects are the rare and occur in less than 0.01% of patients High blood sugar Heart attack Jaundice (yellowing of the skin and eyes) If you think you are experiencing any side effects or if you are worried then see your GP or pharmacist. Does it react with my other medicines? Calcium channel blockers such as amlodipine can interact with some other prescribed medicines; this means that they can affect how they work. Calcium channel blockers should not normally be taken with the following medicines unless you doctor has a good reason. Simvastatin: This is a medication used to lower cholesterol. Care should be taken when simvastatin is taken with amlodipine as it can increase the chance of myopathy (muscle wasting). Alpha- blockers: These are another drug used to treat hypertension so if taking together may cause a large drop in blood pressure (hypotension). Clarithromycin, Erythromycin & Telithromycin: These are antibiotics and can prevent the breakdown of calcium channel blockers. This may cause you to experience more side effects. Phenobarbital: This is an anti- epileptic drug and can reduce the effects of calcium channel blockers. Atazanavir and Ritonavir: These are anti- viral drug and can increase the amount of calcium channel blockers in your blood, which will mean the calcium channel blocker may have a greater effect. Theophylline: This is used in the treatment of asthma and COPD and can increase the amount of calcium channel blockers in your blood, which will mean the calcium channel blocker may have a greater effect. Beta- blockers: These are drugs used to treat heart failure and also to lower blood pressure. When they are taken with negative inotrope calcium channel blockers (diltiazem) they can cause heart block, which can result in an abnormally slow heartbeat. Amiodarone: Is used to treat arrhythmias but there is an increased risk of AV block with diltiazem Carbamazepine and Phenytoin: Drugs used in epilepsy and their effects are increased by diltiazem. Ciclosporin: Is an immunosuppressant drug who s concentration can be increased by diltiazem Colchicine: Is used to treat gout and when given with diltiazem can increase its toxicity Dronedarone: Is used to treat arrhythmias but can cause a slow heart rate when given with diltiazem. You should always tell anyone who is treating you that you are taking calcium channel blockers. This also applies when buying over the counter medicines. What happens if I take too many or miss a dose? not double up on your tablets to make up to the missed dose. Overdose of calcium channel blockers can be very serious and if you have taken too many you should ring for an ambulance and tell that what you have taken. Overdose can cause nausea, vomiting, dizziness, agitation, confusion, or even coma in severe cases. It can also cause your blood pressure to drop very low. Negative inotropes (diltiazem) can cause complete heart block in overdose among other things. Overdose can be treated with thing like activated charcoal, but this should be done in hospital. This leaflet only provides an overview of your medicine and aims to provide answers to people most common questions, it is not comprehensive and if you need more detail you should read the leaflet that comes with your medicine or speak to a healthcare professional such as your doctor or a pharmacist. Hypertension Drug Leaflet 2 Last updated: 4 th February 2013