What Is Substance Abuse?

Substance abuse isn't something you should take lightly. It occurs when you use alcohol, prescription medicine, and other legal and illegal substances too much or in the wrong way.

Substance abuse differs from addiction. Many people with substance abuse problems are able to quit or can change their unhealthy behavior. Addiction, on the other hand, is a disease. It means you can’t stop using even when your condition causes you harm.

Signs of Drug Addiction

Addiction—to prescription and street drugs and alcohol —is a serious problem. If you’re worried that you or a loved one may have an addiction, there are signs to help you know.

Signs you may have a drug problem:

• You keep taking a drug after it's no longer needed for a health problem.
• You need more and more of a substance to get the same effects (called "tolerance"), and you can take more before you feel an effect.
• You feel strange when the drug wears off. You may be shaky, depressed, sick to your stomach, sweat, or have headaches. You may also be tired or not hungry. In severe cases, you could even be confused, have seizures, or run a fever.
• You can't stop yourself from using the drug, even if you want to. You are still using it even though it's making bad things happen in your life, like trouble with friends, family, work, or the law.
• You spend a lot of your time thinking about the drug: how to get more, when you'll take it, how good you feel, or how bad you feel afterward.
• You have a hard time giving yourself limits. You might say you'll only use "so much" but then can't stop and end up using twice that amount. Or you use it more often than you meant to.
• You've lost interest in things you once liked to do.
• You've begun having trouble doing normal daily things, like cooking or working.
• You drive or do other dangerous things (like use heavy machines) when you are on the drug.
• You borrow or steal money to pay for drugs.
• You hide the drug use or the effect it is having on you from others.
• You're having trouble getting along with co-workers, teachers, friends, or family members. They complain more about how you act or how you've changed.
• You sleep too much or too little, compared with how you used to. Or you eat a lot more or a lot less than before.
• You look different. You may have bloodshot eyes, bad breath, shakes or tremors, frequent bloody noses, or you may have gained or lost weight.
• You have a new set of friends with whom you do drugs and go to different places to use the drugs.
• You go to more than one doctor to get prescriptions for the same drug or problem.
• You look in other people's medicine cabinets for drugs to take.
• You take prescribed meds with alcohol or other drugs.

What Is Prescription Drug Abuse?

Prescription drug abuse is when you take a medication for a reason other than why the doctor prescribed it. Experts estimate that more than 18 million people ages 12 and older have used prescription drugs for nonmedical reasons in the previous year. That’s more than 6% of the U.S. population.

Abusing drugs -- even prescription drugs -- can change how your brain works. Most people start by choosing to take these medications. But over time, the changes in your brain affect your self-control and your ability to make good decisions. At the same time, you have intense urges to take more drugs.

Which Prescription Drugs Are Commonly Abused?

The National Institute on Drug Abuse says three classes of prescription drugs are often abused:

Opioids. Since the early 1990s, doctors have been prescribing many more opioid painkillers such as codeine, hydrocodone, morphine (Astramorph, Avinza, Kadian, MS Contin, Oramorph SR), and oxycodone (OxyContin, Percocet, Vicodin). This is partly because of the rising age of the U.S. population and because more people are living with long-term pain.