Bisoprolol

Bisoprolol fumarate is indicated in the management of hypertension. It may be used alone or in combination with other antihypertensive agents.

of its antihypertensive effects has not been completely established. Factors which may be involved include: 1. Decreased cardiac output, 2. Inhibition of renin release by the kidneys, 3. Diminution of tonic sympathetic outflow from the vasomotor centers in the brain. In normal volunteers, bisoprolol fumarate therapy resulted in a reduction of exercise- and isoproterenol-induced tachycardia. The maximal effect occurred within 1-4 hours post-dosing. Effects persisted for 24 hours at doses equal to or greater than 5 mg. Electrophysiology studies in man have demonstrated that bisoprolol fumarate significantly decreases heart rate, increases sinus node recovery time, prolongs AV node refractory periods, and, with rapid atrial stimulation, prolongs AV nodal conduction. Beta 1 -selectivity of bisoprolol fumarate has been demonstrated in both animal and human studies.

The dose of bisoprolol fumarate must be individualized to the needs of the patient. The usual starting dose is 5 mg once daily. In some patients, 2.5 mg may be an appropriate starting dose. If the antihypertensive effect of 5 mg is inadequate, the dose may be increased to 10 mg and then, if necessary, to 20 mg once daily. Patients with Renal or Hepatic Impairment In patients with hepatic impairment (hepatitis or cirrhosis) or renal dysfunction (creatinine clearance less than 40 mL/min), the initial daily dose should be 2.5 mg and caution should be used in dose-titration. Since limited data suggest that bisoprolol fumarate is not dialyzable, drug replacement is not necessary in patients undergoing dialysis. Geriatric Patients It is not necessary to adjust the dose in the elderly, unless there is also significant renal or hepatic dysfunction.

Bisoprolol fumarate is contraindicated in patients with cardiogenic shock, overt cardiac failure, second or third degree AV block, and marked sinus bradycardia.

Cardiac Failure Sympathetic stimulation is a vital component supporting circulatory function in the setting of congestive heart failure, and beta-blockade may result in further depression of myocardial contractility and precipitate more severe failure. In general, beta-blocking agents should be avoided in patients with overt congestive failure. However, in some patients with compensated cardiac failure it may be necessary to utilize them. In such a situation, they must be used cautiously. In Patients Without a History of Cardiac Failure Continued depression of the myocardium with beta-blockers can, in some patients, precipitate cardiac failure. At the first signs or symptoms of heart failure, discontinuation of bisoprolol fumarate should be considered. In some cases, beta-blocker therapy can be continued while heart failure is treated with other drugs.

Safety data are available in more than 30,000 patients or volunteers. Frequency estimates and rates of withdrawal of therapy for adverse events were derived from two U.S. placebo-controlled studies. In Study A, doses of 5, 10, and 20 mg bisoprolol fumarate were administered for 4 weeks. In Study B, doses of 2.5, 10, and 40 mg of bisoprolol fumarate were administered for 12 weeks. A total of 273 patients were treated with 5 to 20 mg of bisoprolol fumarate, 132 received placebo. Withdrawal of therapy for adverse events was 3.3% for patients receiving bisoprolol fumarate and 6.8% for patients on placebo. Withdrawals were less than 1% for either bradycardia or fatigue/lack of energy.

Bisoprolol fumarate 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 bisoprolol fumarate be discontinued for several days before the withdrawal of clonidine. Bisoprolol fumarate should be used with care 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.

Store at 20° to 25°C (68° to 77°F). Protect from moisture.