Prescrire international
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Prescrire international · Jun 2009
Intrauterine devices: an effective alternative to oral hormonal contraception.
(1) Intrauterine devices (IUDs) are placed in the uterine cavity with the objective of providing long-term contraception, mainly by preventing fertilisation. The best-known IUDs contain copper, but there is also an IUD delivering levonorgestrel, a progestin; (2) How effective are these devices, and what are their adverse effects? To answer these questions, we analysed the literature using the standard Prescrire methodology; (3) T-shaped copper IUDs, with a copper surface area of 380 mm2 on 3 arms, and the levonorgestrel-releasing device, have similar contraceptive efficacy as combined oral contraceptives that are used correctly. In contrast, IUDs are more effective than oral contraception used incorrectly; (4) Among IUD users, there are on average about 6 pregnancies per 1000 woman-years. ⋯ Women must be warned that IUDs do not protect them from sexually transmitted diseases; (11) Menstrual bleeding is often heavier in women with cooper IUDs than in women who do not use IUDs, and may be associated with menstrual pain; (12) The levonorgestrel IUD is associated with a marked reduction in menstrual blood loss and irregular bleeding; amenorrhoea occurs in 35% of women after 2 years of use. The levonorgestrel IUD also has hormonal adverse effects such as headache, acne, breast tension and functional ovarian cysts; (13) IUDs can safely be used in breastfeeding women, immediately after a pregnancy, in cases of diabetes or HIV infection, during nonsteroidal antiinflammatory drug therapy, and after an ectopic pregnancy. The only problems occurring in women who have never had children are pain during insertion and more frequent expulsions; (14) A copper IUD is a first-line contraceptive method for women with a history of deep venous thrombosis, pulmonary embolism, or coronary events; (15) It is better to postpone IUD insertion when the woman has a genital tract infection or unexplained vaginal bleeding; (16) IUD insertion is an effective alternative to "morning-after" hormonal contraception.
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Prescrire international · Apr 2009
Drug-eluting coronary stents: many meta-analyses, little benefit.
(1) Angioplasty is one method of unblocking a stenosed coronary artery. A metal stent is sometimes placed in the vessel lumen. Drug-eluting stents coated with an immunosuppressant or cytotoxic drug have been developed with the objective of reducing the risk of recurrent stenosis; (2) We examined the available literature on the efficacy and adverse effects of drug-eluting stents, based on the standard Prescrire methodology; (3) We found a plethora of clinical trials of drug-eluting stents, and numerous meta-analyses, reflecting the broad economic implications of the market for these devices. ⋯ Serious allergic reactions have also been reported; (6) In most cases, especially when the risk of restenosis is low or moderate, it is better to use a bare metal stent. Coronary artery bypass grafting should be considered when there is a high risk of restenosis. Drug-eluting stents are just one alternative to surgery.
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(1) For patients with chronic symptomatic hyperuricaemia who fail to respond to a low purine diet, allopurinol is the standard drug used to prevent complications. This xanthine oxidase inhibitor can, in rare instances, cause severe skin reactions. Probenecid, a uricosuric agent, with which there is also long experience, is a second-line option; (2) Febuxostat, another xanthine oxidase inhibitor, is now authorized for the treatment of hyperuricaemia; (3) Two randomised double-blind trials in 762 and 1072 patients tested various doses of febuxostat compared with a standard dose of allopurinol (33 mg/day). ⋯ In the short term, severe cardiac disorders, based on a composite endpoint, were 4 to 5 times more frequent with febuxostat than with allopurinol. Treatment withdrawals due to hepatic disorders were more frequent with febuxostat than with allopurinol (2.8% versus 0.4%). The relative frequency of severe cutaneous disorders with febuxostat and allopurinol is not known; (6) Clinical evaluation does not include any head-to-head trials of febuxostat versus probenecid; (7) In practice, patients with hyperuricaemia should continue to receive allopurinol as first-line treatment, and probenecid as second-line treatment if allopurinol is ineffective.