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Query: UMLS:C0012833 (dizziness)
 9,689 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A case is reported in which tocainide, a relatively new cardiac antiarrhythmic for oral use, is believed to have caused a delirium. The patient had been admitted to a coronary intensive care unit for the treatment of ventricular arrhythmia and had developed confusion, impairment in concentration and severe anxiety. Her EEG was compatible with metabolic encephalopathy. The clinical picture varied with the use of tocainide so closely that it appeared to be the most likely cause of the delirium. Other factors were taken into consideration but did not seem to adequately disprove this impression. Tocainide has been known to cause minor, transient and treatable side effects in the form of gastrointestinal and central nervous symptoms--mainly nausea, tremor and dizziness. There have also been three case reports of paranoid psychoses. It is suggested that psychiatrists be aware of the above complications as they may have occasion to see patients taking tocainide, especially in consultation-liaison work. A table with the more common side effects and their frequencies is included.
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PMID:Mental changes associated with tocainide, a new antiarrhythmic. 310 61

Tocainide is an antiarrhythmic drug structurally related to lignocaine with similar electrophysiological, haemodynamic and antiarrhythmic effects. In contrast to lignocaine (lidocaine) it is well absorbed after oral administration and has a plasma half-life of about 15 hours. In several open and controlled therapeutic trials in patients with ventricular arrhythmias, often following a myocardial infarction, tocainide has been relatively effective and usually well tolerated. In treating ventricular ectopic beats and/or ventricular tachycardia tocainide has demonstrated effective suppression in 60 to 70% of patients in both open and controlled studies. It has an acute effect when infused in patients with ventricular arrhythmias complicating myocardial infarction, as well as a prophylactic effect when given orally. The majority of these studies have demonstrated tocainide to be more effective than placebo, but trials against other antiarrhythmic agents are few in number and vary in design. One study combining an infusion of tocainide with oral therapy compared to a bolus injection of lignocaine followed by a constant infusion in patients after myocardial infarction, found the two agents to be of similar efficacy. The most common adverse effects are neurological and gastrointestinal in nature, nausea and dizziness occurring most frequently. Adverse effects resulting in termination of therapy have been reported in about 16% of patients. Aggravation of pre-existing heart failure, increased ventricular arrhythmia, deterioration of conduction disturbances, convulsions, and cases of lupus erythematosus syndrome have occasionally been reported. Thus, tocainide appears to offer a worthwhile addition to the other antiarrhythmic agents available for ventricular arrhythmias. However, its relative place in therapy compared with other antiarrhythmic drugs is not yet clearly established.
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PMID:Tocainide. A review of its pharmacological properties and therapeutic efficacy. 641 45

This is a report of the safety evaluation of tocainide in the first 369 patients entered into the American Tocainide Emergency Use Program. This humanitarian protocol has made tocainide available for emergency use in the treatment of life-threatening, intractable ventricular arrhythmias in patients who were unresponsive to or unable to take the approved antiarrhythmic drugs. TAhe most frequent adverse experiences reported were neurologic and gastrointestinal in nature and included dizziness, lightheadedness, tremors, nausea, vomiting, and anorexia. Adverse experiences resulted in the discontinuation of tocainide in 16% of these patients and were transient and reversible with no conclusive evidence of permanent organ injury. Adverse experiences having special relevance to the safety assessment of new antiarrhythmic agents are discussed, including congestive heart failure, arrhythmias and conduction disturbances, convulsions, lupus erythematosus-like illness, and deaths while on therapy. No significant abnormal trends were observed in routine hematologic and biochemical laboratory screening tests or in ophthalmologic or chest x-ray examinations. An evaluation of the effects of chronic tocainide administration of ECG intervals showed no significant change in P-R or QRS intervals but demonstrated a statistically significant decrease in Q-T duration. It is concluded that in patients with life-threatening ventricular arrhythmias, tocainide is a safe agent with a favorable risk-benefit ratio.
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PMID:Safety evaluation of tocainide in the American Emergency Use Program. 677 92