Karvea (Irbesartan 300mg) Tablets

Karvea general information

What is Karvea used for?

Cardiovascular disease covers a range of heart and circulation problems.  Defined risk factors can increase your chances of developing cardiovascular disease.  These risk factors include having high blood cholesterol levels that can result in blocked arteries.  High blood pressure can damage your artery walls and increase stress on your heart.  Lifestyle factors like obesity and smoking can also increase the risk of cardiovascular disease; also conditions like diabetes.  Coronary heart disease is when arteries of the heart become blocked and hardened, which can result in angina (chest pain).  Heart attack is the result of blocked blood flow to the heart muscle, resulting in heart muscle cell damage.  A stroke is the result of a blockage in a blood vessel in the brain or a bleed into the brain, which can cause brain cells to die if not treated quickly.  Karvea tablets 300mg are used to treat high blood pressure, to reduce the risk of heart attack and stroke.  They are also used to treat high blood pressure in patients with type 2 diabetes who also have kidney damage.

High blood pressure

Blood pressure is the force of your heart pumping blood around the body, combined with the resistance of the artery walls to the blood as it is forced into the circulation.  Two blood pressure measurements indicate whether your blood pressure is within the normal range.  Systolic pressure measures the force generated by the heart contracting with each heartbeat as it pumps blood out into the arteries.  Diastolic pressure is the resting phase between each heartbeat when the heart muscle relaxes, and the heart fills with blood.  When your blood pressure is measured, it is expressed as systolic pressure (the highest measure) over diastolic pressure (the lowest measure). 

If the arteries become narrowed or constricted, this increases their resistance, and more force is needed to pump blood around the body.  The increased force causes hypertension, which is high blood pressure when your body is relaxed and at rest.  Essential hypertension is high blood pressure with usually no obvious and identifiable cause.  High blood pressure puts a strain on the heart by increasing its workload and its need for more oxygen.  The extra force of blood in the circulation can damage blood vessels, especially smaller blood vessels, such as those in the kidneys, which can lead to kidney damage.  Hypertension increases the risk of cardiovascular disease, including stroke and heart attack.  There are usually no symptoms of high blood pressure, so you will only know if you have high blood pressure by having a check. 

Diabetic nephropathy

Karvea tablets 300mg are used to treat and prevent the progression of kidney disease if you have high blood pressure and type 2 diabetes, with clinical evidence of kidney damage that prevents their normal function.  This condition is called diabetic nephropathy.  Kidney function is determined by blood and urine tests.  High urine levels of the protein albumin, called proteinuria, indicate that the kidneys allow too much albumin to be filtered out of the blood.  Albumin is an essential blood protein made by the liver that transports several critical blood components around the body, such as hormones, vitamins, and fatty acids.  Albumin also binds to and carries drugs around the body, and it helps regulate your body fluid balance.  By maintaining osmotic pressure in the blood, water stays in the blood instead of leaking into the tissues.  High blood sugar levels seen in diabetes causes damage to the blood vessels, particularly the capillaries, which are the smallest blood vessels.  High blood pressure also puts added strain on these capillaries.  The increased force needed to pump blood around the body damages the small blood vessels and capillaries that supply the kidneys.  These capillaries carry out the filtering process that removes waste from the blood and retains essential electrolytes and proteins.  Damaged capillaries cannot perform this vital function, and this leads to chronic kidney disease. 

How does Karvea work?

Karvea tablets 300mg contain irbesartan an angiotensin II receptor blocker (ARB) that is used to treat hypertension and diabetic nephropathy. 

Angiotensin II is a hormone produced from its precursor angiotensin I, by the action of angiotensin-converting enzyme (ACE) mainly in the lungs but also the blood vessel wall and the kidneys.  Angiotensin II is involved in the renin-angiotensin system that regulates blood pressure.  It has several actions that include causing blood vessels to constrict and narrow (vasoconstriction).  Angiotensin II also regulates fluid balance by promoting salt (sodium and potassium) and water retention by the kidneys, which determines the amount of water removed from the blood by the kidneys.  These actions of Angiotensin II increase blood volume while at the same time reducing blood vessel volume, which increases blood pressure.  Angiotensin II works through a specific receptor on the surface of cells in blood vessels and the kidneys called the Angiotensin II Receptor. 

Irbesartan in Karvea tablets 300mg blocks the binding of Angiotensin II to its receptor in various tissues where Angiotensin II exerts its actions.  This prevents the pressor effects of Angiotensin II (blood pressure increasing) by causing blood vessel dilation or widening and increasing the amount of salt and water removed by the kidneys into the urine.  The combination of these two actions lowers blood pressure and reduces the resistance of blood being pumped around the body, which helps prevent damage to the small blood vessels in the kidney.

What does Karvea contain?

Karvea tablets 300mg contain the active ingredient irbesartan an angiotensin II receptor blocker (ARB) that is used to treat hypertension and diabetic nephropathy. 

What are the side effects of Karvea?

Most medications have some side effects, but they are not experienced by everyone.  Some side effects are commonly experienced when taking Karvea tablets 300mg, but others are not so common, and you should discuss any problems or concerns with your primary care physician. 

Common side effects when taking Karvea include dizziness, hypotension (low blood pressure), orthostatic hypotension (low blood pressure when getting up from sitting or lying down), fatigue, nausea, vomiting, musculoskeletal pain. 

When should Karvea not be used?

Have a talk with your primary healthcare physician before taking Karvea tablets 300mg so that you have a full understanding of what this medicine is for and how to use it.  There are some reasons for not taking a medication; these are called contraindications, and for Karvea you should consider the following before taking Karvea:

• Have you ever had an unusual reaction or an allergy when taking Karvea?
• Are you pregnant or breastfeeding?
• Do you have any problems with your kidneys or your liver?
• Do you have primary hyperaldosteronism, a condition that can increase blood pressure?
• Are you are suffering from a narrowing of the kidney artery, called renal artery stenosis?
• Do you have aortic stenosis (narrowing of the aorta) or mitral heart valve stenosis, (malfunctioning of the mitral valve) or obstructive hypertrophic cardiomyopathy?

What medications interact with Karvea?

Some medicines interact with Karvea tablets 300mg and may affect the way it works, or are affected by Karvea or increase side effects; you should discuss possible interactions with your primary care physician.  These may include other antihypertensives like ACE inhibitors and aliskiren a renin inhibitor used for hypertension, potassium-sparing diuretics like spironolactone, potassium tablets or potassium-containing salt substitutes, lithium for mood swings, non-steroidal anti-inflammatories (NSAID).

If other medications may interact with Karvea, your doctor will discuss these with you. 

How should Karvea be taken and for how long?

You should take your Karvea tablets 300mg swallowed whole with a glass of water, with or without food once daily, at the same time each day.  The dose you take depends on what you are being treated for and your doctor’s recommendation.  It may take up to four weeks for Karvea tablets 300mg to become fully effective in reducing your blood pressure.  It will help control your blood pressure but will not cure it, so you should continue to take your Karvea tablets 300mg for as long as recommended by your doctor, to keep your blood pressure down to normal levels. 

Missed dose of Karvea

If you miss a dose of Karvea tablets 300mg take it as soon as you remember, unless it is time to take the next dose, then skip the missed dose.  Do not take a double dose.

How should Karvea be stored?

You should store your Karvea tablets 300mg below 25°C in a cool dry place.