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Section: Halacha   Category: Food
Beware On Purim - Don't Drink And Daven

The Piskei Teshuvos (based on the Shulchan Aruch and Mishna Brura 95:1 and other poskim) summarizes the halachos of brachos with regard to one in a drunken state.  He breaks the discussion down into three levels of drunkenness and their respective halachic ramifications:

            1.  If one drank less than a reviis of wine not during a meal, or more than a reviis of wine or whiskey (any amount) during a meal, but does not feel like the alcohol affected him at all, he may daven shmoneh esrei and surely may recite all other brachos including bentching.

            2. If one drank more than a reviis of wine, or any amount of whiskey whether or not during a meal, if he feels light headed (even if his speech is not slurred from the drinking) then lechatchila he should not daven shmoneh esrei or recite krias shema until he feels like the alcohol is out of his system.  However, if he will be forced to daven without a minyan later or miss zman tefilah by not davening now, he may daven even while feeling light headed.  However, he should make sure to use a siddur while davening.  Other brachos including bentching are permitted to recite in his current situation. 

            3.  If one drank wine or whiskey and is so drunk that he can not talk properly and can not walk straight then in no situation is it permitted for him to daven even if he will miss zman tefilah.  The Shulchan Aruch writes that if one does daven in such a state it is the equivalent of serving avodah zarah.  With regard to other brachos it is preferred that he wait until he sobers up a little bit before making such brachos but if he makes other brachos in such a state he is yotzei.