<p>Valsartan:</p>

<ul>
	<li><strong>Diuretics</strong>: Patient on diuretics may occasionally experience excessive reduction in blood pressure after initiation of therapy with Valsartan. No drug interaction of clinical significance has been identified with thiazide diuretics.&nbsp;</li>
	<li><strong>Agents increasing Serum Potassium</strong>: Since Valsartan decreases the production of aldosterone, potassium supplements or salt containing potassium substitutes may lead to hyperkalemia.&nbsp;</li>
	<li><strong>Lithium Salts</strong>: As with other drugs which eliminate sodium, lithium clearance may be reduced. Therefore, serum lithium levels should be monitored carefully if lithium salts are to be administered.</li>
	<li>Other drugs showing interaction are Warfarin, Digoxin.</li>
</ul>

<p>Hydrochlorothiazide:</p>

<ul>
	<li>When administered concurrently, the following drugs may interact with thiazide diuretics: alcohol, barbiturates, or narcotics may potentiate antihypertensive effect or orthostatic hypotension may occur.</li>
	<li>Antidiabetic drugs (oral agents and insulin): dosage adjustment of the antidiabetic drug may be required.</li>
	<li>Other antihypertensive drugs give additive effect.</li>
	<li>Cholestyramine and colestipol resins: absorption of Hydrochlorothiazide is impaired in the presence of anionic exchange resins.</li>
</ul>