Drinking is prohibited in Islam. In some Muslim societies, if a person is caught drinking alcohol for the 4th time, he is sentenced to death.
Detailed discussions on the Islamic laws regarding drinking and their historical background are found in these two articles:
In Islamic law there is the somewhat strange principle that if a large amount of anything causes intoxication, a small amount of it is prohibited (Sunan Abu Dawud, book 26, number 3673). It is the prerogative of a religion to make rules for its followers, but this one is clearly not justifiable in scientific terms. Nearly all medicine is poisonous in large amounts, but beneficial in the dosage prescribed by medical doctors.
Further key words and references: