Withdrawal beta-blockers

CENTRALLY ACTING ANTI HYPERTENSIVES BETA-BLOCKERS Risk of withdrawal t BP (rebound t BP) with clonidine and possibly moxonidine Withdrawal of clonidine, and possibly moxonidine, is associated with t circulating catecholamines beta-blockers, especially non-cardioselective ones, will allow the catecholamines to exert an unopposed alpha action (vasoconstriction) Do not withdraw clonidine or moxonidine while a patient is taking beta-blockers. Withdraw beta-blockers several days before slowly withdrawing clonidine and moxonidine... 

Worsening of angina pectoris has been attributed to beta-blocker therapy. The reports include 35 cases in a series of 296 elderly patients admitted to hospital with suspected myocardial infarction in these 35 the pain disappeared within 7 hours of withdrawing beta-blocker therapy (60). 

Major surgery Withdrawing -blockers prior to major surgery is controversial. Protracted severe hypotension and difficulty restarting or maintaining heartbeat have been reported with beta blockers. 

Hypnagogic, hypnopompic onset and offset of sleep (often associated with nightmares) - beta-blockers, benzodiazepine withdrawal... 

In patients using orally administered beta-blockers, abrupt withdrawal may precipitate angina or lead to myocardial infarction or ventricular arrhythmias. 

A controlled withdrawal study design has been used to compare two beta-blockers in respect to their ability to maintain action in the face of a missed dose (Johnson and Whelton, 1994). 

In 27 hypertensive patients aged 65 years or more, randomized to continue atenolol treatment for 20 weeks or to discontinue atenolol and start cilazapril, there was a significant improvement in the choice reaction time in the patients randomized to cilazapril (93). This study has confirmed previous reports that chronic beta-blockade can determine adverse effects on cognition in elderly patients. Withdrawal of beta-blockers should be... 

Hearing SD, Wesnes KA, Bowman CE. Beta blockers and cognitive function in elderly hypertensive patients withdrawal and consequences of ACE inhibitor substitution. Int J Geriatr Psychopharmacol 1999 2 13-7. 

BETA-BLOCKERS X-RAY CONTRAST SOLUTIONS Beta-blockers are associated with T risk of anaphylactoid reactions to iodinated X-ray contrast materials Uncertain, but postulated that beta-receptors have a role in suppressing the release of mediators of anaphylaxis Consider using low-osmolality contrast media and pretreating with antihistamines and corticosteroids. Stopping beta-blockers a few days before the X-ray is associated with a risk of withdrawal t BP and tachycardia a risk-benefit assessment must therefore be made... 

The adverse effects of beta-blockers are usually mild, with occurrence rates of 10-20% for the most common in most studies. Most are predictable from the pharmacological and physicochemical properties of these drugs. Examples include fatigue, cold peripheries, bradycardia, heart failure, sleep disturbances, bronchospasm, and altered glucose tolerance. Gastrointestinal upsets are also relatively common. Serious adverse cardiac effects and even sudden death can follow abrupt withdrawal of therapy in patients with ischemic heart disease. Most severe adverse reactions can be avoided by careful selection of patients and consideration of individual beta-blockers. Hjrpersensitivity reactions have been relatively rare since the withdrawal of practolol. Tumor-inducing effects have not been estabhshed in man. 

Bronchospasm, which can be life-threatening, can be precipitated by beta-blocker eye-drops. Even betai-selective antagonists, such as betaxolol, can cause a substantial reduction in forced expiratory volume. Wheezing and dyspnea have been reported among patients using betaxolol the symptoms resolved after withdrawal. A cross-sectional study has shown that ophthalmologists were more aware than chest physicians about the use of beta-blocker eye-drops by patients with obstructive airways disease patient awareness was also poor (38,107). 

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