Central nervous system considerations in the use of beta-blockers, angiotensin-converting enzyme inhibitors, and thiazide diuretics in managing essential hypertension

Metoprolol-induced psychosis in a young patient

Metoprolol is widely used in cardiology for the treatment of hypertension and arrhythmia. The neuropsychiatric adverse reactions associated with the use of beta-blockers are relatively uncommon, but sometimes take place when poisoning or overdosing on elderly patients. We present a case of a young patient with low-dose metoprolol which induced acute delirium and in whom the symptoms disappeared within 3 days after metoprolol was ceased. The results illustrated that the neuropsychiatric adverse reactions of metoprolol could be developed not only in elderly patients but also in young patients, which has great significance to direct physicians in their clinical practice.

Heart and mind: (2) psychotropic and cardiovascular therapeutics

There is a plausible biological basis for the association between psychiatric morbidity and cardiovascular disease. Anxiety, panic disorder, and depression are common in patients with coronary heart disease and hypertension. Despite this evidence there is poor recognition of anxiety disorders and depression in primary care and hospital medical practice. Concern also surrounds the use of psychotropic drugs in patients with cardiovascular disease. In the first of the two articles on this subject, we highlighted the current evidence regarding the association between cardiovascular and psychotropic conditions. In this second article, we discuss the interaction of the drugs used in the management of these two varied but commonly coexistent group of diseases as well as their relative effects on either system. Finally, we summarise the data regarding the safe use of these medications based on the recommendations from the currently available evidence.

Around the beta-blockers, one more time

We review the pharmacology, pharmacokinetics, and relative costs of beta-blockers, as well as indications for and therapeutic controversies surrounding their use. It is hoped that this discussion will assist clinicians in making informed decisions when choosing a drug for a hospital formulary or a particular patient. Beta-blockers are indicated for a variety of noncardiovascular and cardiovascular conditions, including hypertension, ischemic heart disease, arrhythmias, and prophylaxis of myocardial infarction (MI). These agents compete with catecholamines at beta-adrenoreceptors. They have different ancillary properties, including intrinsic sympathomimetic activity (ISA), cardioselectivity, and membrane stabilizing-activity, and vary in their duration of action, route of elimination, and lipophilicity. Beta-blocking agents decrease oxygen demand by exerting a negative inotropic and chronotropic effect. They also reduce blood pressure and possess antiarrhythmic effects. Beta-blockers penetrate the central nervous system (CNS) to different degrees and can cause a wide variety of CNS adverse effects. Nonselective beta-blockers have been noted to slightly reduce renal blood flow. Nadolol is an exception in that either no change, or even a small increase in renal blood flow, is observed upon initiation of therapy. Beta-blockers also act on the pulmonary bed by preventing beta 2-mediated bronchodilation, thereby exacerbating bronchospastic disease in some patients. Beta-adrenergic blocking agents can potentiate both hypoglycemia and hyperglycemia in diabetic patients. Their effects on total peripheral resistance (TPR) are controversial. Initially it appears that beta-blockade increases TPR. After chronic therapy, however, TPR decreases to or below baseline values. These agents appear to be equally efficacious in the treatment of hypertension, arrhythmias, and ischemic heart disease.(ABSTRACT TRUNCATED AT 250 WORDS)