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Physical Signs Of Drug Use And Abuse

Isaac Alexis, M.D., AAMA, AMP-BC

Medically reviewed by

Isaac Alexis, M.D., AAMA, AMP-BC

February 26, 2019

Single-time use and chronic abuse of a drug manifest itself in several different ways within a person’s body. It is important to be able to recognize the physical signs of drug abuse in order to help keep a loved one safe.

According to the National Institute on Drug Abuse, drug addiction is a brain disease which affects someone’s emotional and physical health. Drug use starts in the brain and it may be difficult to determine if someone has a problem with drugs just by looking at them because they may already have an addiction or abuse tendency without showing any severe signs on the outside.

The collapse of someone’s health due to drug use occurs after regular, consistent use of drugs, but there are some distinctive physical traits and behavioral changes that occur at the beginning stages of drug use that you can use to determine an emerging problem in yourself or a loved one.

Drug Use Vs. Drug Abuse: Is There A Difference?

According to the findings led by the University of Arizona Family and Community Medicine Center, epidemiologists have distinguished different definitions for drug use and drug abuse. Drug use refers to the experimentation or low frequency and occasional use of substances. Drug abuse refers to the regular and compulsive use of drugs.

When determining the physical signs of drug use for yourself or a loved one, you may be looking at someone who takes drugs irregularly and/or as a way to try new experiences with friends. Or, you may be looking at the signs of regular and compulsive drug use, which is more serious and is further down the path towards addiction.

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The Difference Between Physical Dependence And Addiction

One of the key factors when determining if you or a loved one has a drug use problem is taking into account the differences between addiction and physical dependence. According to the National Institute on Drug Abuse, addiction is when someone is not able to stop using a drug or cannot reduce their usage despite the desire to. Physical dependence occurs when the body adapts to the presence of a drug and does not necessarily constitute addiction.

Physical dependence affects a person by developing into tolerance and withdrawal. Tolerance is when a person needs to increase their dosage of a drug to achieve a particular effect. Withdrawal occurs when someone stops taking a drug which may cause exhaustion, headaches, nausea, vomiting, insomnia, sweating, and more. Physical dependence can develop with the long-term use of a drug, and it includes the use of prescription medication, even when taken as instructed by a doctor.

The Common Signs Of Drug Use

There are physical and behavioral signs of drug use to keep in mind. Each type of drug has its own characteristics, including that of illicit drugs as well as prescription drugs. There are a few general signs of drug use that can be seen in almost all types, including:

  • Sudden changes in behavior
  • Mood swings
  • Isolation from family
  • Lowered standards of personal hygiene and grooming
  • Changes in sleeping pattern
  • Red or glossy eyes
  • Runny nose

The common physical signs of drug abuse include:

  • Bloodshot eyes
  • Larger or smaller pupils than normal
  • Sudden weight loss or weight gain
  • Deterioration of physical appearance
  • Unusual smells on the body, clothing, and breath
  • Slurred speech, tremors, or slow, drugged-like movement
  • Jerky, spastic movement

Signs Of One-Time Occurrences Vs. Regular Drug Use

One-time drug use will show minor to noticeable physical signs that don’t necessarily change a person’s normal appearance and tend to be slighter symptoms like bloodshot eyes, unusual smell on clothes or breath, and slightly slurred speech. Regular drug use will generally cause a more drastic, lasting change in the person’s overall appearance, such as sudden changes in weight, chronic bloodshot eyes, and the deterioration of physical appearance and daily grooming.

Physical Signs Of Commonly Abused Drugs

As mentioned earlier, different drugs affect people in different ways. But almost all types of drugs exhibit certain physical signs of which we should all be aware.

  • Marijuana (cannabis) causes red, glassy eyes, loud volume when speaking in a normal setting, inappropriate laughter followed by sleepiness and long-term weight gain or loss.
  • Depressants (Xanax, Valium) cause contracted pupils, drunk-like movement, clumsiness, sleepiness, and slurred speech.
  • Stimulants (amphetamines, methamphetamine, cocaine) cause dilated pupils, hyperactivity, excessive talking, excessive sleeping at odd times, weight loss, and dry mouth and nose.
  • Inhalants (glues and aerosols) can cause watery eyes, runny nose, rashes around the nose and mouth, the appearance of intoxication, drowsiness, and changes in appetite which lead to weight gain or loss.
  • Hallucinogens (LSD, PCP) cause dilated pupils, bizarre behavior, slurred speech, and confused appearance.
  • Heroin (and other opiates) causes contracted pupils, injection marks on the body, no response of pupils to light, odd sleeping schedule, excessive sweating, vomiting, coughing, twitching, and loss of appetite which may lead to weight loss.

Is There A Difference Between Prescription Drug Abuse And Illegal Drug Abuse?

According to the U.S. Food and Drug Administration, someone taking prescription medication can misuse or abuse their medication. Misuse occurs when someone takes a legal prescription drug for a purpose other than the reason it was prescribed. Drug abuse of that prescription occurs when a person taking the medication wants to experience the “high” from the medication.

While prescriptions are legal, the abuse of a prescription can still be called “drug abuse.” Illegal drug abuse differs in that it refers to the use and/or abuse of any illicit drug, such as heroin, cocaine, or LSD.

What many people don’t realize is that drug abuse and addiction often have the same physical and behavioral signs regardless of whether the drug is legal or illegal. Many prescription medications act the same way in the brain as illicit drugs and even include the same active ingredients, affecting a person’s appearance, emotions, and actions in the same way, according to NIH Senior Health.

However, it is important to be gentle with yourself or a loved one who displays signs of drug abuse because people can abuse legal drugs without meaning to. Especially for older citizens, it is possible for people to take medications incorrectly due to impaired vision or memory.

Physical Signs Of Drug Use Signal The Need for Help

If you notice any of these physical signs of drug use in yourself or a loved one, it doesn’t automatically point to illicit drug use or addiction. It signals the need for help and support from loved ones and trained professionals. If you’re interested in learning how you or a loved one can reclaim life and health after the onset of addiction, contact us at We are here to answer your questions and guide you on your journey to a healthy, sober future.

Narconon International- - Signs and Symptoms of Drug Use -

Narconon International- Signs and Symptoms of Prescription Drug Use -

Mayo Clinic - Prescription drug abuse

U.S. Food and Drug Administration - Combating Misuse and Abuse of Prescription Drugs: Q&A with Michael Klein, Ph.D.

NIDA - Is there a difference between physical dependence and addiction?

NIDA - Understanding Drug Use and Addiction

University of Arizona Family and Community Medicine Center - Drug Use vs. Drug Abuse

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