 In this lesson, we will discuss medications used to treat high blood pressure, also known as hypertension. Hypertension is the leading risk factor associated with death in the world. It is affected by a wide variety of factors, including increasing age, black African or Caribbean ethnicity, being overweight, and having a lack of physical activity. Hypertension is typically asymptomatic and only detected through opportunistic screening. Symptoms only manifest when blood pressure reaches very high levels and can include headaches, dizziness and nosebleeds. Blood pressure is determined by the cardiac output balanced against systemic vascular resistance. The process of maintaining blood pressure is complex and involves numerous physiological mechanisms, including arterial beroceptors and the renin-angiotensin aldosterone system. Dysfunction in any of these processes can lead to the development of hypertension. This may be through increased cardiac output, increased systemic vascular resistance, or both. Now, let's do a quick review of blood pressure categories. Blood pressure numbers of less than 120 slash 80 are considered within the normal range. Elevated blood pressure is when readings consistently range from 120 to 129 systolic and less than 80 diastolic. People with elevated blood pressure are likely to develop high blood pressure and less steps are taken to control the condition. Hypertension Stage 1 is when blood pressure consistently ranges from 130 to 139 systolic or 80 to 89 diastolic. At this stage of high blood pressure, doctors are likely to prescribe lifestyle changes and may consider adding blood pressure medication based on risks of atherosclerotic cardiovascular diseases, such as heart attack or stroke. Hypertension Stage 2 is when blood pressure consistently ranges at 140 slash 90 or higher. At this stage of high blood pressure, doctors are likely to prescribe a combination of blood pressure medications and lifestyle changes. If blood pressure readings suddenly exceed 180 slash 120, this is a hypertensive crisis and requires immediate medical attention. Management for hypertension is mainly based on the hypertension stage, risk of developing cardiovascular events and organ damage, as well as taking into account any concomitant diseases, such as diabetes or chronic kidney disease. Lifestyle changes are crucial for all patients, especially in the long term, and include things like quitting smoking, drinking alcohol in moderation, maintaining a healthy weight, reducing dietary sodium and staying physically active. There are four main classes of medications that are used to treat hypertension, ACE inhibitors, angiotensin receptor blockers or ARB, thiozide diuretics, and long-acting calcium channel blockers. There is a lot of variability in terms of how individuals respond to different medications, so it's important to follow up to see how the medications are working. Usually, therapy begins by choosing one medication. Broadly speaking, ACE inhibitors are started in patients at high risk for coronary artery disease, including those with a prior STEMI, heart failure, asymptomatic left ventricular dysfunction, diabetes, and chronic kidney disease. A common side effect of ACE inhibitors is chronic cough, so ARB are often started in patients who don't tolerate ACE inhibitors, mostly because of cough. Thiozide diuretics and calcium channel blockers show very similar efficacy to ACE inhibitors and their first-line therapy in patients of African descent. But diuretics have a lot of metabolic effects, so they can't be given to patients with high blood glucose and cholesterol levels. The blood pressure goal while on medications varies based on the initial blood pressure, age, and other health conditions. But in general, it's ideal to have an out-of-office blood pressure below 135-85 and an office blood pressure below 140-90. If the blood pressure isn't improving within a month, then the dose is usually increased or a second medication from a different class is often started. Some combinations are useful while others aren't. ACE inhibitors and ARB should not be combined and instead either can be combined with a thiozide diuretic or a calcium channel blocker. Angiotensin receptor blockers or ARB for short are a group of medications that help decrease blood pressure and are typically used to treat hypertension or high blood pressure and heart failure. ARB usually end in sartan like Candisartan, Valsartan, herbisartan, and Lossartan and are taken orally. ARB work by binding to angiotensin-pantereceptors on vascular smooth muscles and the adrenal glands, which prevents angiotensin from binding. Normally, when angiotensin combines to these receptors on blood vessels, it causes them to constrict, which increases blood pressure. On the other hand, in the adrenal glands, angiotensin too stimulates the release of aldosterone, which increases the absorption of sodium and water in the kidneys. This results in increased blood volume, which also increases blood pressure. Once ARB are administered, angiotensin can't bind to angiotensin receptors, which decreases vasoconstriction as well as aldosterone release by the adrenals. This causes natural uresis or excretion of sodium along with water by the kidneys. In this way, ARB effectively lower blood pressure. However, ARB can also cause some side effects. The most common ones are mild and nonspecific and include headache, dizziness, and drowsiness. ARB have also rarely been associated with the development of angioedema, which is a fluid accumulation and swelling of the eyes, lips, tongue, pharynx, and glottis, and can be life-threatening. Other side effects include hypotension, tachycardia, and hypoglycemia. Finally, ARB decrease potassium excretion in the urine, and this could lead to hyperkalemia, so it's important for clients who are taking ARB to avoid taking potassium supplements and salt substitutes that contain potassium. Deuretics are medications that act on the kidneys to increase the production of urine, therefore elimination of water from the body. There are five main types of deuretics, carbonic anhydrase inhibitors, osmotic deuretics, loop deuretics, potassium-sparing deuretics, and last but not least, thiozide and thiozide-like deuretics, which we'll get intimately acquainted with during this video. The major indication for deuretics is for the management of hypertension and edomatis states. Since these medications cause water loss through the urine, it leads to decreased plasma volume and cardiac output resulting in lower blood pressure. So what is a thiozide, and what is a thiozide-like deuretic? Well, all these medications have the same effect, the different stems from their chemical structure. Thiozide and thiozide-like deuretics are medications that block the sodium chloride importer in the distal convoluted tubule in order to increase urine output. Thiozides are used mainly as first line anti-hypertensive agents since they decrease plasma volume. This also makes them useful as a second line therapy to treat edomatis states caused by conditions like heart failure or cirrhosis. Calcium channel blockers are drugs that reduce the movement of calcium into cells of the heart and vessels. This reduces the strength of heart contractions and relaxes the arteries, allowing them to remain more open, lowering blood pressure. There are two different types of calcium channel blockers, which are called dehydropyridines and non-dehydropyridines. Dehydropyridines block calcium channels located in the muscle cells of the heart and arterial blood vessels, thereby reducing the entry of calcium ions into the cell. By blocking these channels, calcium channel blockers promote blood vessel dilation, as well as changes in heart function, including reductions in heart rate, the strength of contractility, and speed of conduction within the heart. Non-dehydropyridines widen blood vessels in the same way as dehydropyridines. However, they have additional effects on the heart that can help control a rapid heart rate. Calcium channel blockers can cause several side effects, such as fatigue and swelling in the abdomen, feet, and legs. Anyone who experiences worsening side effects should talk to a doctor about changing medications or reducing the dosage.