Get help today 888-341-7785 or sign up for 24/7 text support.
American Addiction Centers National Rehabs Directory

Common Signs of Drug Use and Addiction

Substance use disorders (SUDs) are a complex condition in which a person cannot control their use of a substance despite having negative consequences.1 Individuals with an SUD are often focused on using a specific substance (e.g., alcohol or illicit drugs) to the point where their use affects their day-to-day life.1 The most severe form of SUD is addiction.1

SUDs can lead to problems at home, school, or work and can have devastating effects on one’s emotional and physical wellbeing. If you are worried about your own or a loved one’s drug use, knowing the common signs of drug use and treatment options is important. Read on to learn about the behavioral, emotional, and physical changes that may occur from specific drugs.

What Is Substance Use Disorder?

SUDs can lead to a person’s inability to control their use of substances, such as alcohol, drugs, or medications.2 Some people experience moderate to severe symptoms as a result of SUDs, with addiction being the most severe form.2

A person with SUDs may experience symptoms including:3

  • Taking the substance in larger amounts or for longer than intended.
  • Trying to cut down or control the use of the substance unsuccessfully.
  • Spending a significant amount of time obtaining, using, or recovering from the substance.
  • Experiencing strong cravings for the substance.
  • Trouble fulfilling major obligations at home, school, or work.
  • Engaging in risky behavior as a result of using the substance.
  • Interference with the person’s personal and social life as a result of using the substance.
  • Giving up important activities to use the substance.


After alcohol and tobacco, marijuana is the most used addictive drug in the U.S.4 Also referred to as bud, chronic, Mary Jane, or pot, more than 14 million people had a past-year marijuana use disorder in 2020.5 Marijuana can produce behavioral, emotional, and physical changes including:6

  • Behavioral: Shortly after smoking marijuana, users may appear very relaxed or sleepy. Marijuana can impair coordination, causing the user to move in ways that may seem awkward. A heightened craving for food is typical with marijuana use.
  • Emotional: Problem-solving and thinking may be affected under the influence of marijuana and users may find their memory is impaired. When taken in high doses or when high-potency marijuana is consumed, users may experience delusions, hallucinations, and psychosis.
  • Physical: Users may have dry, bloodshot eyes, prompting them to use eye-wetting drops frequently. Since marijuana smoke can irritate the lungs, users may experience coughing and an increase in phlegm. Their clothes may emanate the scent of marijuana, which has a pungent and slightly sweet odor.


Cocaine, also known as blow, coke, or snow, is an addictive stimulant drug from the leaves of the coca plant.7 The behavioral, emotional, and physical changes cocaine may cause include:7

  • Behavioral: A person on cocaine may act as though they have little self-restraint, meaning they may engage in activities that they would normally find embarrassing, frightening, or stressful. Cocaine disrupts sleep, and frequent users can act violently. Whether injected, smoked, or snorted, cocaine imbues the user with energy, allowing them to stay active longer than normal. Instead of acting sleepy, someone on cocaine may act jittery and the increased energy may speed up their speech.
  • Emotional: The promise of extreme happiness attracts many to cocaine. However, this feeling is very brief and often, quickly replaced with depression or a very intense emotional low. Difficulty recalling memories and shifts in mood are common with cocaine use. This drug can create feelings of ambivalence toward people and activities that the user used to find engaging.
  • Physical: Because cocaine is a stimulant, it increases metabolism and can lead to rapid weight loss. People who use cocaine regularly may have a gaunt appearance. In users who snort the drug, the nose may bleed frequently. 

LSD (Acid)

LSD (D-lysergic acid diethylamide) is a powerful mind-altering chemical. LSD is a clear or white odorless material made from lysergic acid, and can cause several behavioral, emotional, and physical changes including:8

  • Behavioral: LSD often creates a sense of distorted surroundings. These episodes can last up to 12 hours with one dose. With larger quantities, users are more likely to experience hallucinations. These visualizations may prompt strange behaviors as the person attempts to interact with or respond to what they think they are seeing. Their speech may be slurred, bordering on incoherent.
  • Emotional: Variance in emotions is a hallmark of LSD use. Erratic and unpredictable emotions can cause extreme and frequent mood changes. Users may experience a disproportionate sense of panic.
  • Physical: When combined with the other signs, sweaty hands and an increase in underarm perspiration are other signs that a person is using LSD. Their pupils may also appear larger than normal.


Psilocybin comes from certain types of mushrooms found in tropical and subtropical regions of Mexico, South America, and the U.S. Psilocybin can produce behavioral, emotional, and physical changes including:8

  • Behavioral: Intense laughter typically begins 20-25 minutes after ingesting a mushroom. Someone who takes mushrooms may experience vomiting, vomiting, uncoordinated movements, and weakness.
  • Emotional: Someone who takes mushrooms may feel confused and uncertain about their surroundings, which may cause them to feel “spaced out.” In some cases, users hallucinate and may be so mentally impaired that they cannot identify the hallucinations for what they are.
  • Physical: Their eyes may be dilated and may not focus on what is in front of them. They may also be nauseated by mushroom intake.


Heroin, also known as black, horse, or smack, is an opioid made from the natural substance morphine, which is derived from the seed pod of various opium plants.9 Heroin can produce behavioral, emotional, and physical changes including:9

  • Behavioral: Heroin tends to slow breathing and cause drowsiness. Frequent nodding off can be a problem for someone who uses heroin.
  • Emotional: Heroin envelops users in a sense of relaxation. Mental activity declines and may be replaced by depression and lethargy.
  • Physical: Marks from repeated injections appear on the arms of many people who use heroin. They may also neglect good hygiene habits.


Methamphetamine, also known as meth or Tina, is a highly addictive substance that affects the central nervous system (CNS).10 When a person uses meth, the amount of dopamine in the brain increases, which can strongly reinforce drug-taking behavior.10

  • Behavioral: Individuals addicted to meth report being able to stay awake for days at a time. They may accomplish many tasks in a short period because they do not stop to sleep. Meth use can look similar to mania from bipolar disorder, with erratic behavior, increased energy, irritability, and rapid speech.
  • Emotional: Agitation, paranoia, and a sense of being on high alert can stem from meth use. Some people who use meth feel increased aggression and may hallucinate while taking the drug.
  • Physical: Meth use can create a dramatic shift in the appearance of the skin, from healthy to acne-prone and sagging. “Meth mouth” can also occur which is marked by infected gums and rotting teeth.

Drug Addiction Treatment Options

When some people struggle with addiction, they may deny that they have a problem. Others may be reluctant to enter treatment due to cost, fear, or lack of support. However, once they overcome any reservations and are ready to enter treatment, there are several types of addiction treatment options to choose from.

  • Inpatient treatment: This type of treatment offers 24-hour supervised care in a comfortable, safe setting. Inpatient rehab typically uses a variety of therapeutic approaches including individual and group therapy sessions.
  • Outpatient treatment: With outpatient rehab, patients live at home and go to treatment during the day. Common levels of care in outpatient rehab include standard outpatient, intensive outpatient (IOP), and partial hospitalization (PHP).

In inpatient or outpatient rehab, patients can also be assessed and treated for dual diagnosis, which means they have two or more conditions presenting at the same time or one after the other.

Looking for the Signs of Alcohol or Drug Addiction

Addiction looks different in everyone. People suffering from addiction may resort to desperate measures like stealing to fund their disease. They may abandon family and long-time friends to associate with people who also use alcohol or drugs. Often, these may be the first tip-offs that an individual is grappling with addiction. Remember that one sign alone does not indicate your loved one has a problem. Instead, watch for a combination of the signs that accompany each drug.

If you are searching for rehabs near me for you or a loved one, most insurance plans cover at least part of, if not all, addiction treatment. You can call the number on the back of your insurance card or check your insurance coverage online by filling out the form below.