Substance abuse is when you take drugs that are not legal. It’s also when you use alcohol, prescription medicine, and other legal substances too much or in the wrong way.

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

Commonly Abused Drugs

Both legal and illegal drugs have chemicals that can change how your body and mind work. They can give you a pleasurable “high”, ease your stress, or help you avoid problems in your life.

Alcohol

Alcohol affects everyone differently, but if you drink too much and too often, your change of an injury or accident goes up. Heavy drinking also can cause liver and other health problems or lead to a more serious alcohol disorder. If you’re a man and you drink more than four drinks on any day more than 14 in a week, you’re drinking too much. For women, heavy drinking means more than three drinks in one day or more than 7 drinks a week.

One drink is:

• 12 ounces of regular beer
• 8-9 ounces of malt liquor, which has more alcohol than beer
• 5 ounces of wine
• 1 ½ ounces of distilled spirits like vodka & whiskey

Prescription and Over-the-Counter (OTC) Medicine

• These can be just as dangerous and addictive as illegal drugs. You can abuse medicine if you:
• Take medicine prescribed for someone else
• Take extra doses or use a drug other than the way it’s supposed to be taken
• Take the drugs for non-medical reasons

Types of prescription drugs that are most often abused include:

• Opioid pain relievers
• Medicine used to treat attention deficit hyperactivity disorder
• Anxiety medicine

The most commonly abused OCT drugs are cough and cold medicine that have dextromethorphan, which in high doses can make you feel drunk or intoxicated.

Heroin

This illegal drug is the natural version of man-made prescription opioid narcotics. Heroin gives you a rush of good feelings at first, but when it wears off, everything slows down. You’ll move and think more slowly, and you may have chills, nausea, and nervousness. You may feel a strong need to take more heroin to feel better.

Cocaine

This drug speeds up your whole body. When you use cocaine, you may talk, move, or think very fast. You may feel happy and full of energy, but your mood may then shift to anger. You may feel like someone is out to get you. It can cause you to do things that don’t make sense.

Using cocaine for a long time will lead to strong cravings for the drug.

Marijuana

Marijuana can you make feel silly and laugh for no reason. Or you may feel sleepy and for things that just happened. Driving while high on pot is just as dangerous as drunk driving. Heavy marijuana use can leave some people “burned out” and not think or care about much.

Cigarettes and Other Tobacco Products

You may not thing of these as drugs but tobacco has the chemical called nicotine that gives you’re a little rush of pleasure and energy. The effect can wear off fast and leave you wanting more. You can abuse and get addicted to the nicotine in cigarettes, just like other drugs.

**Source-https://www.webmd.com/mental-health/addiction/substance-abuse#1