There have been many people who have died from this sort of a combination. According to the article in this link
thousands of Americans die every year from such combinations. They cite the number of deaths in 2004 as 3,792.
The article speculates that people are dying much more from these combinations now because more pills are available without prescriptions and because people are sent home more quickly from hospitals. Less supervision means that there are more chances to mix drugs and alcohol in fatal ways.
The association of alcohol with drugs, including painkillers and sedatives, can damage the liver and can lead to fatal consequences.Many of the medicines that could be taken without medical prescription are included in this category. The combination of antihistamines, cough suppressants and other medications that relieve symptoms of colds and flu can cause alcohol poisoning.
Alcohol consumption along with administration of antidepressants can cause high blood pressure while taking sleeping pills and drinking same time, may reduce heart rate frequency.