Generic

Olmesartan Medoxomil + Hydrochlorothiazide

Indications

The combination of olmesartan medoxomil and hydrochlorothiazide is suitable for the treatment of hypertension.

Pharmacology

Angiotensin II is formed by angiotensin I in a reaction catalyzed by angiotensin-converting enzyme (ACE). It is an effective vasoconstrictor and the main vasoactive hormone of the renin-angiotensin system. It is also the pathology of hypertension. An important part of physiology. It also stimulates the adrenal cortex to secrete aldosterone. Olmesartan selectively blocks the binding of angiotensin II to AT 1 receptors found in many tissues (such as vascular smooth muscle, adrenal glands) to block the vasoconstriction and aldosterone secretion of angiotensin II. Exposure studies have shown that Olmesartan is a competitive and reversible AT 1 receptor inhibitor. Olmesartan does not inhibit ACE (kinase I, an enzyme that converts angiotensin I into angiotensin II and breaks down bradykinin).

Hydrochlorothiazide is a thiazide diuretic. Thiazides affect the renal tubular electrolyte reabsorption mechanism and directly increase the excretion of approximately equal amounts of sodium and chloride. Indirectly, the diuretic effect of hydrochlorothiazide reduces plasma volume, which increases plasma renin activity, increases aldosterone secretion and urinary potassium loss, and reduces serum potassium. The renin connection is mediated by angiotensin II. Therefore, the co-administration of angiotensin II receptor antagonists tends to reverse the potassium loss associated with these diuretics.

Dosage & Administration

Hypertension: The usual starting dose is 20/12.5 mg one tablet once daily. Dosing should be individualized. Depending on the blood pressure response, the dose may be titrated at intervals of 2-4 weeks to two tablets 40/25 once daily.

Interaction

Olmesartan: In healthy volunteers, olmesartan medoxomil combined with hydrochlorothiazide, digoxin or warfarin did not report significant drug interactions. Olmesartan medoxomil is not metabolized by the cytochrome P450 system and has no effect on P450 enzymes; therefore, it is not expected to interact with drugs that inhibit, induce, or are metabolized by these enzymes.

Hydrochlorothiazide: When administered at the same time, the following drugs may interact with thiazide diuretics:

• Alcohol, barbiturates or anesthetics: May enhance orthostatic hypotension.
• Hypoglycemic drugs (oral drugs and insulin): The dose of hypoglycemic drugs may need to be adjusted.
• Other antihypertensive drugs: additive effect.
• Corticosteroids, ACTH.
• Lithium.

Contraindications

The combination of olmesartan and hydrochlorothiazide is contraindicated in patients allergic to any component of this product. Because it contains hydrochlorothiazide, patients who have anuria or are allergic to other sulfonamides should not use this product.

Side Effects

Common side effects are nausea, headache, dizziness, hyperuricemia, upper respiratory infection, and urinary tract infection. Other adverse reactions include chest pain, back pain, peripheral edema, abdominal pain, indigestion, gastroenteritis, and diarrhea.

Pregnancy & Lactation

The safety and effectiveness in breastfeeding mothers and pregnancy have not been established. The drug should be discontinued in these cases.

Precautions & Warnings

Serum electrolytes should be measured regularly at appropriate time intervals to detect potential electrolyte imbalances, such as hypokalaemia, hyponatremia, and hypochloric alkalosis. Some patients treated with thiazides may develop hyperuricemia.  Renal function altered.

Therapeutic Class

Combined antihypertensive preparations

Storage Conditions

Store in a cool and dry place, away from light and moisture. Keep out of reach of children.

Pharmaceutical Name

Opsonin Pharma Ltd.