Prescrire international
-
Prescrire international · Feb 2006
Antiviral drugs in influenza: an adjunct to vaccination in some situations.
(1) Influenza is a common acute respiratory disease due to a virus that causes annual seasonal epidemics. Three major pandemics occurred in the 20th century, in 1918-1919, 1957 and 1968, mainly due to genetic variants of type A influenza virus. (2) In temperate regions the incidence of hospitalisation increases during annual influenza epidemics. More than 90% of deaths linked to influenza involve people over 65 years of age. (3) The clinical manifestations of influenza virus infection are non specific. ⋯ Under these conditions, treatment should be started within 48 hours after contact with a person who has flu-like symptoms during a seasonal epidemic; residents in institutions in which influenza cases occur may also qualify for preventive treatment. Other preventive measures should also be used, including immediate vaccination, case isolation, use of face masks, and more frequent hand washing. (16) During seasonal influenza epidemics due to viral strains against which the current vaccine is of limited effectiveness, the utility, target populations and optimal duration of preventive antiviral treatment must be determined by examining the groups most at risk and the severity of complications. (17) Most flu-like syndromes are not due to the influenza virus, and the preventive effect of antiviral drugs on complications in persons at risk has not yet been demonstrated. (18) In practice, antiviral drugs are not an alternative to influenza vaccination, but may be a useful adjunct in some situations. It is best to limit their use to short-term prophylaxis of vulnerable persons in situations where the risk of contracting influenza virus infection is high.
-
(1) Nicorandil, a vasodilator marketed for symptomatic relief of angina pectoris, is known to cause mouth ulcers, which can sometimes be very large. (2) Cases of anal ulceration have also been reported, associated with pain and, sometimes, a bloody discharge. These anal ulcerations heal very slowly (several weeks) after nicorandil withdrawal.