Abrupt cessation of nadolol therapy: a cause of the discontinuation syndrome.

Abrupt cessation of antihypertensive drug therapy is potentially hazardous, especially when beta blocker drugs are suddenly withdrawn from patients with ischemic heart disease, when unstable angina, myocardial infarction and sudden death may result. A milder 'discontinuation syndrome' may follow abrupt cessation of many drugs commonly used to treat hypertension. The syndrome consists of symptoms and signs suggesting sympathetic nervous system overactivity, with or without an accompanying rise in blood pressure. If this rise occurs, pre-treatment levels may be reached or even exceeded. Treatment of this condition is simple once it is recognized. Reintroduction of the drug or drugs in question, perhaps in reduced dosage, is effective management and guidelines are suggested for the safe withdrawal of antihypertensive drug therapy where it is medically indicated. Nadolol (Corgard) has not previously been reported as a cause of the discontinuation syndrome. A case is described where abrupt cessation of nadolol provoked unusually prolonged and severe signs of sympathetic overactivity on two occasions in the same patient.