Vicodin® is prescribed for moderate to severe pain and has become popular as a drug of abuse because of its narcotic content. The active ingredient in Vicodin, hydrocodone, is a synthetic opiate, in the same category as morphine or heroin.
Vicodin is only available in the United States as a combination product with acetaminophen.
There is an historical reason why hydrocodone only come as a mix with acetaminophen (Tylenol) -- it actually has more to do with marketing than any practical medical use.
Vicodin is a Schedule III drug
When a drug is first marketed, the DEA and FDA look at its potential for abuse and classify it according to a numbered schedule. Morphine, as an example, is in schedule II, giving it the highest addictive potential. Vicodin (and generics) would be in the same schedule if they were single ingredient agents, but by mixing the hydrocodone with acetaminophen, it receives the lower classification of schedule III. The regulations differ enough between the two classifications that doctors will more readily prescribe the lower classification. In other words, by making a combination, more sales are generated.
Acetaminophen adds risk
Whether having the acetaminophen in the tablet helps with pain relief is disputed, but having it there raises a new risk for addicts. The effects of the powerful narcotic (hydrocodone) dull with time and abusers are likely to raise the dose considerably as they become tolerant. However, tolerance does not develop to the effects of the acetaminophen in the pill which can cause liver and kidney damage in high doses. This means that addicts who take more and more Vicodin are at risk, not from overdose by the narcotic, but by the Tylenol they take simultaneously.
Savvy addicts come to learn the hazards of Vicodin and may either attempt to remove the acetaminophen or change drugs. They hope to get a similar effect without the danger of Tylenol overdose. Unfortunately, this leads to other problems with Vicodin addiction.