Ziac drug interactions

Overdosage topics
General Bisoprolol Fumarate Risk of Anaphylactic Reaction Hydrochlorothiazide
 * Alcohol, barbiturates, or narcotics
 * Antidiabetic drugs (oral agents and insulin)
 * Other antihypertensive drugs
 * Cholestyramine and colestipol resins
 * Corticosteroids, ACTH
 * Lithium

General
ZIAC may potentiate the action of other antihypertensive agents used concomitantly. ZIAC should not be combined with other beta-blocking agents. Patients receiving catecholamine-depleting drugs, such as reserpine or guanethidine, should be closely monitored because the added beta-adrenergic blocking action of bisoprolol fumarate may produce excessive reduction of sympathetic activity. In patients receiving concurrent therapy with clonidine, if therapy is to be discontinued, it is suggested that ZIAC be discontinued for several days before the withdrawal of clonidine. ZIAC should be used with caution when myocardial depressants or inhibitors of AV conduction, such as certain calcium antagonists (particularly of the phenylalkylamine [verapamil] and benzothiazepine [diltiazem] classes), or antiarrhythmic agents, such as disopyramide, are used concurrently.

Bisoprolol Fumarate
Concurrent use of rifampin increases the metabolic clearance of bisoprolol fumarate, shortening its elimination half-life. However, initial dose modification is generally not necessary. Pharmacokinetic studies document no clinically relevant interactions with other agents given concomitantly, including thiazide diuretics, digoxin, and cimetidine. There was no effect of bisoprolol fumarate on prothrombin times in patients on stable doses of warfarin.

Risk of Anaphylactic Reaction
While taking beta-blockers, patients with a history of severe anaphylactic reaction to a variety of allergens may be more reactive to repeated challenge, either accidental, diagnostic, or therapeutic. Such patients may be unresponsive to the usual doses of epinephrine used to treat allergic reactions.

Hydrochlorothiazide
When given concurrently the following drugs may interact with thiazide diuretics.

Alcohol, barbiturates, or narcotics
potentiation of orthostatic hypotension may occur.

Antidiabetic drugs (oral agents and insulin)
dosage adjustment of the antidiabetic drug may be required.

Other antihypertensive drugs
additive effect or potentiation.

Cholestyramine and colestipol resins
Absorption of hydrochlorothiazide is impaired in the presence of anionic exchange resins. Single doses of cholestyramine and colestipol resins bind the hydrochlorothiazide and reduce its absorption in the gastrointestinal tract by up to 85 percent and 43 percent, respectively.

Corticosteroids, ACTH
Intensified electrolyte depletion, particularly hypokalemia. Pressor amines (eg, norepinephrine) - possible decreased response to pressor amines but not sufficient to preclude their use. Skeletal muscle relaxants, nondepolarizing (eg, tubocurarine) - possible increased responsiveness to the muscle relaxant.

Lithium
generally should not be given with diuretics. Diuretic agents reduce the renal clearance of lithium and add a high risk of lithium toxicity. Refer to the package insert for lithium preparations before use of such preparations with ZIAC.