Karvezide

The dose of Karvezide to be used depends on the dose of irbesartan or hydrochlorothiazide that the patient was taking before. Doses higher than 300 mg irbesartan and 25 mg hydrochlorothiazide once a day are not recommended. Karvezide may be added to some other treatments for hypertension.

Karvezide contains two active substances, irbesartan and hydrochlorothiazide.

Irbesartan is an ‘angiotensin-II-receptor antagonist’, which means that it blocks the action of a hormone in the body called angiotensin II. Angiotensin II is a powerful vasoconstrictor (a substance that narrows blood vessels). By blocking the receptors to which angiotensin II normally attaches, irbesartan stops the hormone having an effect, allowing the blood vessels to widen.

Hydrochlorothiazide is a diuretic, which is another type of treatment for hypertension. It works by increasing urine output, reducing the amount of fluid in the blood and lowering the blood pressure.

The combination of the two active substances has an additive effect, reducing the blood pressure more than either medicine alone. By lowering the blood pressure, the risks associated with high blood pressure, such as having a stroke, are reduced.

The European Commission granted a marketing authorisation valid throughout the EU for Karvezide on 16 October 1998.

The CHMP decided that Karvezide’s benefits are greater than its risks and recommended that it be given marketing authorisation.

The most common side effects with Karvezide (seen in between 1 and 10 patients in 100) are dizziness, nausea (feeling sick) or vomiting, abnormal urination, fatigue (tiredness), and increases in blood urea nitrogen (BUN, a breakdown product of protein), creatinine (a breakdown product of muscle) and creatine kinase (an enzyme found in muscles). For the full list of all side effects reported with Karvezide, see the package leaflet.

Karvezide must not be used in people who are hypersensitive (allergic) to irbesartan, hydrochlorothiazide, sulfonamides, or any of the other ingredients. It must not be used in women who are more than three months pregnant. Its use during the first three months of pregnancy is not recommended. Karvezide must also not be used in patients who have severe liver, kidney or bile problems, blood potassium levels that are too low or blood calcium levels that are too high. Karvezide in combination with aliskiren-containing medicines (used to treat essential hypertension) must not be used in patients with diabetes, or moderate or severe kidney impairment.

Care must be taken when using Karvezide with other medicines that have an effect on blood potassium levels. The full list of these medicines is given in the package leaflet.

Karvezide is a medicine that contains two active substances, irbesartan and hydrochlorothiazide. It is available as tablets (150 mg or 300 mg irbesartan and 12.5 mg hydrochlorothiazide; 300 mg irbesartan and 25 mg hydrochlorothiazide).

Karvezide is used in adults who have essential hypertension (high blood pressure) that is not adequately controlled by irbesartan or hydrochlorothiazide alone. ‘Essential’ means that the hypertension has no obvious cause.

The medicine can only be obtained with a prescription.

Irbesartan on its own has been approved in the European Union (EU) since 1997 under the names Karvea and Aprovel. It can be used with hydrochlorothiazide to treat hypertension. The studies of Karvea / Aprovel used with hydrochlorothiazide as separate tablets were used to support the use of Karvezide. Further studies were also carried out with doses of 300 mg irbesartan in combination with 25 mg hydrochlorothiazide. The main measure of effectiveness was the reduction in diastolic blood pressure (the blood pressure measured between two heartbeats).

Karvezide was more effective than placebo (a dummy treatment) and than hydrochlorothiazide alone in reducing diastolic blood pressure. Increasing the dose to 300 mg irbesartan and 25 mg hydrochlorothiazide may give a further decrease in blood pressure.