This is a very interesting topic that you hear about from time to time, but the reasons why are rarely discussed so that people understand just how risky and dangerous this can be. Some people think that this only applies to someone who might be classified as an alcoholic and is on prescription medication, and sadly this is no the case. Even one or two drinks can interfere with the medication you are taking. Another thing to keep in mind, is that this not only applies to prescriptions, but over the counter medications as well.
Mixing even a small amount of alcohol with even an over the counter medication can cause thing like high blood pressure and when your blood pressure elevates, you become a candidate for things such as a stroke or a heart attack. Some medications mixed with alcohol, may cause drowsiness which if you are behind the wheel could lead to a fatal situation for you as well as those around you.
Another factor to think about is timing. For those who have forgot about the allergy medication you took earlier in the day and now you are going out to dinner with friends or family and someone has ordered you an alcoholic beverage without asking you if you wanted one. Just push it aside and tell who ever ordered you the drink that you are not drinking tonight because you are taking medication that can not be mixed with alcohol. You should not drink alcohol at all, if you might possibly need medication later in the day or evening for even things like a headache. Some headache medications say do not take with alcohol in your system and if you had a drink even four or five hours earlier, it could still be in your system without you even knowing it depending on how much you have had.