Signs & Symptoms of Addiction (Physical & Mental)

4 min read · 12 sections

What is Addiction?

Addiction, as defined by the American Society of Addiction Medicine, is a chronic disease that changes the reward centers in the brain. While this can involve behaviors like gambling, shopping, or sex, addiction is most understood in terms of substance abuse that fundamentally changes how dopamine and other neurotransmitters associated with the reward system are managed in the brain. Behavioral characteristics of addiction involve an inability to control behaviors, cravings and withdrawal symptoms, and physical side effects, including damage to major organ systems.

Signs of Drug or Alcohol Addiction

Signs of drug addiction include frequent intoxication, hangover or illness, and paraphernalia related to substance abuse. Behavioral changes may also indicate drug or alcohol addiction, and these include:

  • Problems at work or school, including poor performance, lateness or absenteeism, and social dysfunction
  • Loss of energy or motivation
  • Neglecting one’s appearance
  • Spending excessive amounts of money on the substance
  • Obsessing about the next dose, ensuring a consistent supply of the substance, and worrying about the next source of the substance
  • Performing risky behaviors while intoxicated
  • Experiencing withdrawal symptoms when unable to take the drug
  • Developing tolerance, so it’s necessary to take more to feel the original euphoria
  • Stealing to get the drug
  • Lying about consumption habits, or getting defensive or aggressive when questioned about consumption
  • Compulsively taking the drug or being unable to stop taking it

Different drugs have different signs of intoxication, different side effects, and different withdrawal symptoms. The signs and symptoms of abuse for specific substances are outlined below.


Alcohol is a legal intoxicating substance in the United States if the person is at least 21 years old. Despite its legal status, about 17 million adults, ages 18 and older, struggle with alcohol use disorder, or alcoholism.

Signs that a person is struggling with alcohol use disorder include:

close up of alcohol bottle spilling with glass

  • Being drunk on a regular basis, evident by slurred speech, loss of coordination, impaired attention and memory, and poor decision-making
  • Drinking beyond moderation on a regular basis (Moderation is defined as seven drinks per week.)
  • Feeling sick after drinking and using alcohol to ease the symptoms
  • Drinking alone, in the mornings, or giving up other activities specifically to drink
  • Taking risks or participating in risky behaviors, like driving drunk
  • Drinking in secret
  • Changes in appearance as health declines
  • Choosing to drink rather than eat meals
  • Behavioral differences when the person is drunk versus when they are sober
  • Blacking out frequently due to drinking too much on a regular basis
  • Long-term health issues, including memory problems, stomach upset, heart and blood pressure problems, and damage to the liver and kidneys
  • Mental health problems, including anxiety, depression, or insomnia, depending on how much alcohol the person has consumed
  • Being unable to stop drinking


Symptoms of marijuana intoxication and potential addiction include:
Marijuana flower and joint

  • Frequent intoxication on the drug, indicated by sleepiness, relaxation, mild euphoria, hunger (“the munchies”), pain relief, loss of coordination, depression, or anxiety or paranoia
  • Side effects like decreased short-term memory, dry mouth, red eyes, impaired perception, and cravings for the drug
  • In some cases, an anxiety disorder or psychosis triggered by use
  • Lung infections, if smoked; digestive issues, if eaten
  • Constant need for more marijuana to feel normal or good
  • Withdrawal symptoms, including nightmares, insomnia, nausea, disinterest in food, or depression
  • Spending too much money on acquiring the drug and neglecting other financial obligations
  • Forgoing or quitting social obligations, work, or school to consume marijuana


This category mostly includes prescription painkillers that are derived from morphine, a synthetic form of the chemical found in the opium poppy. Common opioids include hydrocodone (Vicodin, Lortab, Norco, Zohydro), oxycodone (OxyContin, Percocet, Oxycocet, Tylox), fentanyl, methadone, codeine, and tramadol. Opioid addiction is an epidemic in the United States, with many people who can no longer obtain prescription opiates turning to heroin, fentanyl, or other, more potent substances. Recently, this has led to thousands of deaths across the country.
Signs of opioid addiction and abuse include:

Open Bottle of Pills

  • Consistent intoxication on the drug, including signs like drowsiness, euphoria, depression, constipation, pinpoint pupils, confusion, delirium, changes in appetite, and depressed breathing
  • Experiencing withdrawal symptoms, many of which manifest as severe flu symptoms, when unable to take the drug
  • Escalating use, or changing how the drug is taken (e.g., taking the drug orally initially but then crushing and snorting the pills to get a more rapid effect)
  • Running out of prescriptions early, doctor shopping to get multiple prescriptions, stealing money to buy more drug, or purchasing it on the black market
  • Experiencing pain and feeling the need to take more of the drug to alleviate the pain
  • Prioritizing the drug over work, school, friends, and family
  • Suffering an overdose


Heroin is an opioid drug, so addiction to this substance has many manifestations that are similar to those of prescription opioid abuse. Heroin is a Schedule I drug, according to the Drug Enforcement Administration, because it offers no medical benefit.

Heroin is typically injected into a vein – although it can be snorted – and it has a very rapid onset, usually taking effect within 5-15 minutes. The pleasurable effects do not last long, and side effects begin within an hour after the drug is injected.
heroin dependency

Signs of heroin abuse include:

  • Paraphernalia like needles, tubing, used spoons, and lighters
  • Inability to stop taking it, even if one wants to stop
  • Euphoria, followed by reduced consciousness or “nodding,” a condition where a person slips in and out of consciousness
  • Infections from sharing needles, including hepatitis, HIV, bacterial blood infections, myocardial infarctions; other infections, including pneumonia, tuberculosis, or skin diseases from poor living conditions; and liver and kidney disease
  • Other symptoms as listed above


Addiction to benzodiazepines is sometimes referred to as a shadow epidemic because misuse or nonmedical use of these drugs is rising rapidly, as are overdoses involving benzodiazepines, but it is rarely discussed as an epidemic, like opioid addiction. In 2013, 30 percent of overdose deaths involved benzodiazepines like Klonopin, Xanax, or Valium, either alone or in combination with other drugs.

Signs of benzodiazepine addiction and abuse include:

Pills and medicine container lying on white background

  • Acting drunk and exhibiting signs like loss of coordination, slurred speech, reduced inhibitions, memory loss, and blurred or double vision
  • Confusion and cognitive impairment
  • Physical weakness
  • Withdrawal symptoms mimicking psychological syndromes that benzodiazepines are prescribed to treat, such as anxiety, paranoia, panic attacks, and insomnia
  • Increased risk of developing seizures when the drug is not consumed
  • Changes in appetite and weight
  • Headaches
  • Trouble breathing
  • Coma


Methamphetamines are a potent, illegal stimulant in the US. These are synthetic drugs that can cause very severe side effects, and they are highly addictive.

Signs of meth addiction include:

methamphetamine in a plastic bag on table

  • A rush of dopamine and serotonin that induces a sense of wellbeing, happiness, excitability, and even invincibility
  • Delusions, commonly paranoia or feelings of grandeur
  • Changes in reflexes
  • Depression when the initial euphoria wears off
  • Compulsive movements, such as scratching or picking at the skin
  • Excessive excitement or talkativeness
  • Aggression, irritability, or mood swings
  • Reduced need for sleep and food
  • Hallucinations
  • Tremors
  • Dry mouth, bad breath, and damage to the teeth and gums
  • Headache
  • Jaw clenching
  • Dehydration
  • Elevated body temperature, which may become dangerous

One sign of meth addiction is “tweaking,” a process that begins when a person ingests a large amount of meth and does not sleep for 3-15 days. The person will be irritable, paranoid, and aggressive or fearful. Tweaking can cause brain damage from loss of sleep and excessive amounts of neurotransmitters in the brain.


This drug is one of the most potent stimulants, and it is commonly found as a white powder or as whitish or yellowish rocks called crack cocaine. Cocaine releases excessive amounts of dopamine into the brain, leading to an excitable euphoria similar to that produced by meth.

Symptoms of intoxication, and potential addiction to, cocaine or crack cocaine include:

Cocaine lines on table with dollar bill

  • Dilated pupils
  • Talkativeness and excitability
  • Increased body temperature
  • Raised heart rate and blood pressure, which could lead to a stroke or heart attack
  • Decreased appetite or desire for sleep
  • Insomnia and restlessness
  • Aggression
  • Paranoia and anxiety
  • Depression or anxiety when coming off the drug or experiencing withdrawal
  • Intense cravings
  • Lying or stealing to get the drug
  • Performing risky behaviors
  • Developing tolerance, so more cocaine is required to experience the original euphoria


Anabolic steroids are the most common type of steroid that is abused. Unlike other drugs of addiction, steroids do not involve intense euphoria, although some anecdotal evidence suggests that people feel “high” because they still take the drug compulsively. Steroids increase muscle mass, physical energy, and extroversion; however, these effects come with serious long-term health consequences.
Doping in sport and steroid abuse concept with a dumbbell
People who struggle with anabolic steroid abuse often have an underlying body image problem, which may involve depression, body dysmorphia, or an eating disorder.
Anabolic steroid abuse can be identified by:

  • Rapid increase in muscle mass
  • Changes in body hair, weight, and breast size
  • Increased aggression
  • Manic behavior
  • Hallucinations or delusions
  • Acne
  • Baldness
  • Long-term health consequences, including heart attack, stroke, blood clots, liver cancer, infections in the veins or skin around injection site, endocarditis, hepatitis, or HIV

Find Addiction Treatment Near You

Get Help to End Drug Addiction

This list contains several of the most common substances of abuse, but people struggle with abuse of countless other drugs.

Regardless of the type of drug abused, continued drug abuse and addiction cause serious problems in virtually every aspect of life. Thankfully, with professional help, people can stop abusing drugs for good and embrace healthier, happier lives.

Professional rehabilitation programs offer various specialties to address individual needs, so anyone who struggles with addiction can overcome the problem and maintain long-term sobriety.

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