Drug Testing

Drug Testing in Humans: Studying Potential for Abuse

Nearly any drug used to treat illness also poses certain risks. One such risk, generally limited to drugs that act on the central nervous system, is that the drug will be abused because of those effects. Such a drug is said to have "abuse potential" or "abuse liability." If it has important medicinal uses, it may still be available by prescription, but legal controls will be placed on how it can be prescribed. New drugs are tested to determine their potential for abuse so that both the public and the medical profession can be warned about the need for appropriate caution when using them.

Conducting tests on humans serves several purposes in the development of safer and more effective drugs. When research done on laboratory animals shows that a drug might have abuse potential, these findings must be confirmed with tests on humans. Humans who participate in testing describe what kinds of things they notice when they take a particular drug. Testing drugs on humans can also help determine appropriate dose levels and dosage forms to ensure safety and efficacy while minimizing unwanted side effects. Finally, testing in humans helps reduce the availability of abusable drugs to those who are likely to abuse them.

In most studies, the human volunteer subjects are experienced to some degree as drug users. Some studies involve people with histories of intensive drug use and abuse over extended periods. These people make good test subjects because they are similar to those most likely to abuse drugs. Other studies use students or volunteers whose misuse and abuse of drugs or alcohol has been mostly recreational. Tests in these people can determine whether certain widely available medications, such as sleeping pills or appetite suppressants, are likely to be abused. Participants are often selected on the basis of some special features (such as anxiety levels or level of alcohol consumption) in order to determine the extent...