Prescrire international
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Prescrire international · Jun 2005
Tramadol oral solution: new drug. Poorly evaluated and potentially dangerous in children.
(1) Codeine, either used alone or in combination with paracetamol, is the standard step-2 opiate analgesic for children from the age of one year. (2) An oral solution of tramadol, another step-2 opiate analgesic, was recently approved in France for the treatment of children at least three years of age. (3) The only clinical trials of tramadol in this age group focused on short-term treatment of postoperative pain. Tramadol has not been compared with codeine, ibuprofen, or correctly dosed paracetamol (step-1 analgesic). Tramadol has been compared with diclofenac, a nonsteroidal antiinflammatory drug, in a trial that included patients over 11 years of age (including adults), but the results of this trial are uninformative because patients were not blinded and no separate paediatric subgroup analysis was carried out. (4) The adverse effects of tramadol in children appear to be mild but frequent (especially vomiting). (5) As with codeine, deaths have been reported following accidental overdose with oral tramadol in children. (6) There is no justification for prescribing such a potentially harmful drug with poorly documented efficacy.
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Prescrire international · Apr 2005
Stiripentol: new preparation. Severe myoclonic epilepsy of infancy: promising.
(1) Severe myoclonic epilepsy of infancy (Dravet's syndrome) is associated with multiple seizures and progressive onset of mental retardation. Available antiepileptics (valproic acid and clonazepam/clobazam) are only partially effective, even when used in combination. (2) Stiripentol is intended to be added to the valproate + clobazam combination when the latter is ineffective. (3) In a two-month double-blind trial, 9 of 21 infants remained seizure-free when stiripentol was added to the valproate-clobazam combination, whereas all 20 infants receiving a placebo instead of stiripentol continued to have seizures. (4) Two follow-up studies lasting two and three years and involving 37 and 46 children showed that about 20% of patients had a major benefit (fewer seizures) when stiripentol was added to inadequately effective valproate-clobazam combination therapy. ⋯ Stiripentol was only moderately effective in adolescents. (5) Stiripentol has common and sometimes serious adverse effects such as loss of appetite (with ensuing weight loss), drowsiness and insomnia. Stiripentol inhibits several cytochrome P450 isoenzymes, including CYP 3A4, creating a high risk of interactions, especially with co-administered antiepileptics. (6) The stiripentol dose strengths currently available in France are unsuitable for infants weighing less than 10 kg. (7) In practice, given the severity of this type of myoclonic epilepsy of infancy, the addition of stiripentol to ongoing but ineffective valproate-clobazam combination therapy is justified, even though the treatment is somewhat difficult to manage and has not yet been fully evaluated.
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Prescrire international · Apr 2005
Comparative StudyAnastrozole: new indication. Adjuvant treatment of non metastatic breast cancer: useful for some patients.
(1) For postmenopausal women with hormone-receptor-positive breast cancer, the reference adjuvant treatment after surgical excision is tamoxifen (an anti-estrogen), taken orally at a dose of 20 mg/day for 5 years. (2) Anastrozole is the first aromatase inhibitor to be licensed for this use in France. (3) Marketing authorisation was based on the short-term results of a double-blind trial comparing anastrozole (1 mg/day) with tamoxifen (20 mg/day) in 9366 women. The trial is planned to last five years. The results obtained after median follow-up of 4 years showed no difference between the groups in overall survival (109 deaths in each group). ⋯ The following adverse events were statistically less common with anastrozole than with tamoxifen: hot flushes (35.0% versus 40.3%), metrorrhagia, venous thromboembolism (1.1% versus 1.8%), ischaemic stroke (1.1% versus 2.3%), and endometrial cancer (3 versus 15 cases at 4 years). (5) In practice, anastrozole may be beneficial for women who cannot use tamoxifen, such as those at high risk of thrombosis. Anastrozole costs ten times more per day than tamoxifen. Tamoxifen remains the reference adjuvant treatment for all other women.
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Prescrire international · Dec 2004
Comparative StudyAntibiotics for acute group A streptococcal pharyngitis.
(1) Since the 1940s, a large number of comparative randomised placebo-controlled trials have evaluated antibiotic therapy for pharyngitis, initially parenteral benzathine benzylpenicillin, then oral phenoxymethylpenicillin (penicillin V). Our literature search identified a Cochrane meta-analysis of all these trials, with the exception of one published in 2003. (2) When group A betahemolytic streptococci (group A streptococci) are present in the throat, antibiotic therapy accelerates symptom relief (particularly fever and pain) by a day or two. This has been shown with 7-day treatments but not with 3-day treatments. ⋯ Moreover, antibiotics affect the bacterial ecology, encouraging resistance among some bacterial species other than group A streptococci. (7) A strategy based on the use of a clinical diagnostic score, followed by a rapid test if the score is intermediate, seems to be the best way of restricting antibiotics to patients with pharyngitis due to group A streptococci. (8) In patients with group A streptococcal pharyngitis, a strategy of starting antibiotics only after 48 hours of symptoms delays symptom control but seems to reduce the risk of relapse. According to a clinical trial in patients with pharyngitis from all causes, advising patients to postpone antibiotic therapy reduces antibiotic use by about 85%, without increasing the risk of serious clinical complications. (9) In practice, immediate antibiotic therapy is justified for patients with severe symptoms or signs of progression to locoregional suppuration, and when the local incidence of acute rheumatic fever is high. In other situations, whether or not group A streptococci are involved, antibiotic therapy should be started only if symptoms do not begin to improve after 48 hours of symptomatic treatments.
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Prescrire international · Oct 2004
Comparative StudySt John's wort and depression: slight efficacy at best, many drug interactions.
(1) St John's wort has been widely used for centuries as a herbal remedy. Dozens of trials, of variable quality, have examined the therapeutic value of St John's wort. Published meta-analyses show that St John's wort extracts are more effective than placebo in patients with mild and moderate depression. (2) Trials show that St John's wort is about as effective as tricyclic and serotonin reuptake inhibitor antidepressants. (3) There is insufficient evidence to determine the efficacy of St John's wort in patients with more severe depression. (4) Few, mostly minor adverse effects have been reported, but there may be a small risk of serotonin syndrome and cutaneous photosensitisation. (5) Some components of St John's wort interfere with CYP3A4, one of the main cytochrome P450 isoenzymes. ⋯ St John's wort reduces the efficacy of several drug groups including: immunosuppressants (risk of graft rejection), oral contraceptives (risk of pregnancy), oral anticoagulants (risk of thrombosis), and HIV protease inhibitors. It can also reduce the bioavailability of digoxin. (6) In practice, St John's wort is an inappropriate treatment for severe depression. It is, however, an acceptable option for short-term management of transient depressed mood when there is no risk of drug interactions and when the patient is properly informed of this risk. (7) In short, the risk-benefit balance of St John's wort is no better than that of standard antidepressants, mainly because of the risk of drug interactions.