Because of the potential for serious adverse effects, LONITEN Tablets are indicated only in the treatment of hypertension that is symptomatic or associated with target organ damage and is not manageable with maximum therapeutic doses of a diuretic plus two other antihypertensive drugs.At the present time use in milder degrees of hypertension is not recommended because the benefit-risk relationship in such patients has not been defined.LONITEN reduced supine diastolic blood pressure by 20 mm Hg or to 90 mm Hg or less in approximately 75% of patients, most of who had hypertension that could not be controlled by other drugs.
LONITEN Tablets are contraindicated in pheochromocytoma, because it may stimulate secretion of catecholamines from the tumor through its antihypertensive action.LONITEN is contraindicated in those patients with a history of hypersensitivity to any of the components of the preparation.
Congestive Heart Failure—concomitant use of an adequate diuretic is required—LONITEN Tablets must usually be administered concomitantly with a diuretic adequate to prevent fluid retention and possible congestive heart failure; a high ceiling (loop) diuretic is almost always required.
Body weight should be monitored closely.
If LONITEN is used without a diuretic, retention of several hundred milli-equivalents of salt and corresponding volumes of water can occur within a few days, leading to increased plasma and interstitial fluid volume and local or generalized edema.
Diuretic treatment alone, or in combination with restricted salt intake, will usually minimize fluid retention, although reversible edema did develop in approximately 10% of nondialysis patients so treated.
Ascites has also been reported.
Diuretic effectiveness was limited mostly by diseas-erelated impaired renal function.
The condition of patients with pre-existing congestive heart failure occasionally deteriorated in association with fluid retention although because of the fall in blood pressure (reduction of afterload), more than twice as many improved than worsened.
Rarely, refractory fluid retention may require discontinuation of LONITEN.Provided that the patient is under close medical supervision, it may be possible to resolve refractory salt retention by discontinuing LONITEN for 1 or 2 days and then resuming treatment in conjunction with vigorous diuretic therapy.