Active ingredient: warfarin
In case of chronic alcohol consumption, decreases anticoagulant effect due to increase metabolism of oral anticoagulants.
In case of acute alcohol ingestion, the effect is the opposite: increased anticoagulant effect by metabolic inhibition.
Taking alcohol repeated times in small or moderate amounts , can increase anticoagulant effect.
Some studies suggest that alcohol can displace the binding of warfarin to plasma proteins. This phenomena may alter the pharmacokinetics of th? anticoagulant.
It is advisable that patients avoid taking alcohol in any amount while they are under treatment with anticoagulants both oral or parenteral, as it can result in hemorrhagic phenomena, especially when are concurrently using other medicines.
In a study on a small group of patients with alcohol dependence, a week after cessation of alcohol consumption, was detected an increase of plasmatic free fraction of warfarin by 19% (p <0.05).
The study's authors call the attention to the possibility that they may present clinically important changes in the anticoagulant effect resulting from changes in the proportion of free drug in the intervals between doses, due to fluctuations this fraction, although the mean free drug concentration remains unchanged.
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