possibly codeine
Meth
alcohol
Prescription drugs are the most abused by this generation.
The most commonly abused prescription drugs are: narcotics, anxiolytics like Valium/Ativan/Xanax, and amphetamines. Any controlled substance has the potential for abuse as well as psychological and/or physiological addiction.
Alcohol is the most commonly-abused and most dangerous substance in Western society. Other drugs are pretty bad, too. Get over the "alcohol and drugs" thing; alcohol IS a drug.
The most common is oxycodone, followed by tranquilizers such as Xanax and other painkillers like Vicodin and Percocet.
This answer may vary.. but the drugs most used by young people that I know about is weed, Ectasy, GHB, Ketamine other wise known by Special K or Cereal, crystal meth just to name a few off the top of my head
Yes, if the drug test happens to be testing for opioids. (Most all of them will since opioids are one of the most commonly abused drugs.)
Alcohol.
indicators show that hydrocodone is the most commonly abused narcotic analgesic
Sugar
Yes, most drugs of abuse have a lethal dose.