Prescrire international
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Prescrire international · Apr 2007
Comparative StudySertindole: new drug. Another "atypical" neuroleptic; QT prolongation.
(1) The first-line drug for the treatment of schizophrenic disorders is a neuroleptic such as haloperidol. Amisulpride may be preferable when haloperidol causes unacceptable neurological reactions. Overall, the risk-benefit balance of more recent, so-called atypical neuroleptics is no better. (2) Sertindole, a neuroleptic, was first marketed in 1996 in several European countries before being withdrawn two years later because of numerous cardiac adverse effects. ⋯ However, it causes weight gain. Sertindole also has alpha blocking properties, which can cause postural hypotension and reduce ejaculate volume; it also has atropinic effects (constipation, dry mouth, etc.). (5) Sertindole provokes a dose-dependent increase in the QT interval more frequently than haloperidol in comparative trials, and apparently more frequently than other 'atypical' neuroleptics such as risperidone and olanzapine. Sertindole has been suspected of increasing cardiovascular mortality but this has not been established. (6) Sertindole is metabolised by cytochrome P450 isoenzymes CYP 2D6 and CYP 3A4, hence a high risk of pharmacokinetic interactions. (7) In practice, when haloperidol has to be withdrawn because of adverse effects, especially neurological reactions, it is better to continue to resort to amisulpride, for example, with close monitoring of adverse effects, rather than expose patients to the potential dangers of sertindole.
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Prescrire international · Apr 2007
Comparative StudyIvabradine: new drug. Best avoided in stable angina.
(1) The first-line symptomatic treatment for stable angina is a betablocker such as atenolol. Some calcium channel blockers such as verapamil, and the potassium channel agonist amlodipine, are second-line alternatives. Long-acting nitrate derivatives have poorly documented efficacy but can be used as adjuvants or as third-line treatments. (2) Ivabradine is derived from verapamil but appears to have a different mechanism of action, mainly lowering the heart rate. ⋯ Three double-blind randomised controlled trials lasting 3 to 4 months, based on surrogate exercise endpoints, failed to show that ivabradine was any more effective than atenolol or amlodipine, or even more effective than placebo in patients already treated with amlodipine. (4) In two one-year double-blind randomised controlled trials comparing ivabradine with atenolol or amlodipine in a total of 704 patients, ivabradine was no more effective than the comparators in preventing angina attacks. (5) In head-to-head comparisons, serious coronary events were significantly more frequent with ivabradine than with atenolol (3.8% versus 1.5%). Severe arrhythmias were also more frequent with ivabradine than with atenolol (1.3% versus 0.7%) or amlodipine (0.6% versus 0.2%). (6) Ivabradine provokes phosphenes (flashing lights, etc.) in about 17% of patients in the short term. Information is inadequate to assess possible risks of retinal toxicity in the long term. (7) Ivabradine is metabolised by cytochrome P450 isoenzyme CYP 3A4; there is therefore a potentially high risk of pharmacokinetic interactions. (8) In practice, for long-term preventive treatment of angina it is better to avoid ivabradine and to use better-documented treatments: preferably a betablocker, or, if a betablocker cannot be used, verapamil or amlodipine.
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Non metastatic prostate cancer: avoid over-interpretation of flawed clinical trial evidence.
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Prescrire international · Feb 2007
Alcohol withdrawal syndrome: how to predict, prevent, diagnose and treat it.
(1) When people who are physically dependent on alcohol stop drinking, they experience an alcohol withdrawal syndrome. The symptoms generally resolve spontaneously within a week, but more severe forms may be associated with generalised seizures, hallucinations and delirium tremens, which can be fatal. (2) We carried out a literature review in order to obtain answers to the following questions: how to predict or rapidly diagnose a severe alcohol withdrawal syndrome; how to prevent and treat this syndrome; how to manage severe forms; and how to deal with the risk of vitamin B1 deficiency. (3) The main risk factors for severe withdrawal syndrome are: chronic heavy drinking; a history of generalised seizures; and a history of delirium tremens. (4) Anxiety, agitation, tremor, excessive sweating, altered consciousness and hallucinations are signs of a severe withdrawal syndrome. (5) Individual support and effective communication seem to reduce the risk of severe withdrawal syndrome. (6) Oral benzodiazepines are the best-assessed drugs for preventing a severe alcohol withdrawal syndrome, particularly the risk of seizures. When given for a maximum of 7 days, the adverse effects are usually mild. (7) Clinical trials of other antiepileptics suggest they are less effective than benzodiazepines, and their addition to benzodiazepine therapy offers no tangible advantage. (8) Betablockers increase the risk of hallucinations, and clonidine increases the risk of nightmares, and the efficacy of these two drugs is not well documented. ⋯ Outpatient withdrawal may be more appropriate for patients who are at low risk of developing severe withdrawal syndrome. (13) A large proportion of alcohol-dependent patients were excluded from trials of withdrawal strategies. These include elderly patients, patients with serious psychiatric or somatic disorders, and patients who are also dependent on other substances. (14) An oral benzodiazepine is the best-assessed treatment for a single episode of generalised seizures or hallucinations during alcohol withdrawal. (15) In randomised comparative trials benzodiazepines were more effective than neuroleptics in preventing delirium-related mortality. Currently, with appropriate fluid-electrolyte support, continuous monitoring of vital signs, and respiratory support if necessary, the mortality rate for delirium tremens is under 3%. (16) In practice, patients who are attempting to stop drinking alcohol need close personal support and communication, and a reassuring environment, as well as regular monitoring for early signs of a withdrawal syndrome; the latter may require benzodiazepine therapy.