What It Is: LSD (lysergic acid diethylamide) is a hallucinogenic drug. Hallucinogens change the way people sense the world around them. Sometimes Called: acid, sugar cubes, white lightning, dose, tripping, blotter How It's Used: LSD is odorless, colorless, and tasteless. It can be painted onto small squares of paper that people lick or swallow. What It Does: LSD causes the senses of space, distance, and time to become altered. People say they "hear" colors or "see" sounds, and have strange feelings and strong emotions. Many users refer to an "acid trip" — when the effects don't let up and can last for up to 12 hours at a time. LSD also can cause "bad trips" — when users experience panic, confusion, sadness, and scary images. Bad reactions can happen with the first use and a user may have flashbacks later, experiencing the feelings of a bad trip even after the drug wears off. Because LSD also affects judgment and behavior, users might find themselves in a dangerous situation. Physical changes include increased heart rate and blood pressure, muscle twitches and shaking, dilated pupils, sweating, sleeplessness, and loss of appetite. Back to Articles Related Articles Drugs: What to Know It's not hard to find drugs, and sometimes it may seem like everyone's doing them or wanting you to do them. But there are downsides (and dangers) to taking drugs. Read More Dealing With Addiction Find out what you can do if you think you or a friend has a drug or alcohol addiction - from recognizing the warning signs to suggestions to help you stay clean. Read More Bath Salts Bath salts are powerful stimulant drugs that increase brain and central nervous system activity. Find out how they can affect you in this article for teens. Read More Rohypnol Rohypnol is a powerful sedative that has a reputation as a "date rape" drug. Find out more about it in this article for teens. Read More Methamphetamine (Meth) Meth is a powerful stimulant drug that's extremely addictive and destructive. Find out how it works and why it's smart to avoid it. Read More School Counselors School counselors can give you all sorts of tips and support on solving problems and making good decisions. But how do you meet with a counselor and what is it like? Find out here. Read More Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor. © 1995-2021 KidsHealth®. All rights reserved. Images provided by The Nemours Foundation, iStock, Getty Images, Veer, Shutterstock, and Clipart.com.