Cannabis use disorder is recognized in the fifth version of the "Diagnostic and Statistical Manual of Mental Disorders" (DSM-5), which added cannabis withdrawal as a new condition. In the United States, the average adult who seeks treatment has consumed cannabis for over 10 years almost daily and has actively attempted to quit six or more times.

The DSM-5 guidelines for diagnosis of opioid use disorder require that the individual has significant impairment or distress related to opioid uses. In order to make the diagnosed two or more of eleven criteria must be present in a given year:

1. More opioids are taken than intended

2. The individual is unable to decrease the amount of opioids used

3. Large amounts of time are spent trying to obtain opioids, use opioids, or recover from taking them

4. The individual has cravings for opioids

5. Difficulty fulfilling professional duties at work or school

6. Continued use of opioids leading to social and interpersonal consequences

7. Decreased social or recreational activities

8. Using opioids despite it being physically dangerous settings

9. Continued use despite opioids worsening physical or psychological health (i.e. depression, constipation)

10. Tolerance

11. Withdrawal

For a diagnosis of benzodiazepine dependence to be made, the ICD-10 requires that at least 3 of the below criteria are met and that they have been present for at least a month, or, if less than a month, that they appeared repeatedly during a 12-month period.

- Behavioral, cognitive, and physiological phenomena that are associated with the repeated use and that typically include a strong desire to take the drug.

- Difficulty controlling use

- Continued use despite harmful consequences

- Preference given to drug use rather than to other activities and obligations

- Increased tolerance to effects of the drug and sometimes a physical withdrawal state.

These diagnostic criteria are good for research purposes, but, in everyday clinical practice, they should be interpreted according to clinical judgement. In clinical practice, benzodiazepine dependence should be suspected in those having used benzodiazepines for longer than a month, in particular, if they are from a high-risk group. The main factors associated with an increased incidence of benzodiazepine dependence include:

- Dose

- Duration

- Concomitant use of antidepressants

Benzodiazepine dependence should be suspected also in individuals having substance use disorders including alcohol, and should be suspected in individuals obtaining their own supplies of benzodiazepines. Benzodiazepine dependence is almost certain in individuals who are members of a tranquilizer self-help group.

Research has found that about 40 percent of people with a diagnosis of benzodiazepine dependence are not aware that they are dependent on benzodiazepines, whereas about 11 percent of people judged not to be dependent believe that they are.

When assessing a person for benzodiazepine dependence, asking specific questions rather than questions based on concepts is recommended by experts as the best approach of getting a more accurate diagnosis. For example, asking persons if they "think about the medication at times of the day other than when they take the drug" would provide a more meaningful answer than asking "do you think you are psychologically dependent?". The Benzodiazepine Dependence Self Report Questionnaire is one questionnaire used to assess and diagnose benzodiazepine dependence.

No medications have been found effective for cannabis dependence as of 2014, but psychotherapeutic models hold promise.

The most commonly accessed forms of treatment in Australia are 12-step programmes, physicians, rehabilitation programmes, and detox services, with inpatient and outpatient services equally accessed. In the EU approximately 20% of all primary admissions and 29% of all new drug clients in 2005, had primary cannabis problems. And in all countries that reported data between 1999–2005 the number of people seeking treatment for cannabis use increased.

Treatment options for cannabis dependence are far fewer than for opiate or alcohol dependence. Most treatment falls into the categories of psychological or psychotherapeutic, intervention, pharmacological intervention or treatment through peer support and environmental approaches. Screening and brief intervention sessions can be given in a variety of settings, particularly at doctor's surgeries, which is of importance as most cannabis users seeking help will do so from their general practitioner rather than a drug treatment service agency.

Clinicians differentiate between casual users who have difficulty with drug screens, and daily heavy users, to a chronic user who uses multiple times a day. The sedating and anxiolytic properties of THC in some users might make the use of cannabis an attempt to self-medicate personality or psychiatric disorders.

There are efforts to decrease the number of opioids prescribed in an effort to decrease opioid use disorder and deaths related to opioid use.

Sending a letter to patients warning of the adverse effects of long-term use of benzodiazepines and recommending dosage reduction has been found to be successful and a cost-effective strategy in reducing benzodiazepine consumption in general practice. Within a year of the letter's going out, there was found to be a 17% fall in the number of benzodiazepines being prescribed, with 5% of patients having totally discontinued benzodiazepines. A study in the Netherlands reported a higher success rate by sending a letter to patients who are benzodiazepine-dependent. The results of the Dutch study reported 11.3% of patients discontinuing benzodiazepines completely within a year.

There are several different screening tools that have been validated for use with adolescents such as the CRAFFT Screening Test and in adults the CAGE questionnaire.

Some recommendations for screening tools for substance misuse in pregnancy include that they take less than 10 minutes, should be used routinely, include an educational component. Tools suitable for pregnant women include i.a. 4Ps, T-ACE, TWEAK, TQDH (Ten-Question Drinking History), and AUDIT.

In the United States, cocaine use results in about 5,000–6,000 deaths annually.

Some medical systems, including those of at least 15 states of the United States, refer to an Addiction Severity Index to assess the severity of problems related to substance use. According to DARA Thailand, the index assesses potential problems in seven categories: medical, employment/support, alcohol, other drug use, legal, family/social, and psychiatric.

Addiction is a complex but treatable condition. It is characterized by compulsive drug craving, seeking, and use that persists even if the user is aware of severe adverse consequences. For some people, addiction becomes chronic, with periodic relapses even after long periods of abstinence. As a chronic, relapsing disease, addiction may require continued treatments to increase the intervals between relapses and diminish their intensity. While some with substance issues recover and lead fulfilling lives, others require ongoing additional support. The ultimate goal of addiction treatment is to enable an individual to manage their substance misuse; for some this may mean abstinence. Immediate goals are often to reduce substance abuse, improve the patient's ability to function, and minimize the medical and social complications of substance abuse and their addiction; this is called "harm reduction".

Treatments for addiction vary widely according to the types of drugs involved, amount of drugs used, duration of the drug addiction, medical complications and the social needs of the individual. Determining the best type of recovery program for an addicted person depends on a number of factors, including: personality, drugs of choice, concept of spirituality or religion, mental or physical illness, and local availability and affordability of programs.

Many different ideas circulate regarding what is considered a successful outcome in the recovery from addiction. Programs that emphasize controlled drinking exist for alcohol addiction. Opiate replacement therapy has been a medical standard of treatment for opioid addiction for many years.

Treatments and attitudes toward addiction vary widely among different countries. In the US and developing countries, the goal of commissioners of treatment for drug dependence is generally total abstinence from all drugs. Other countries, particularly in Europe, argue the aims of treatment for drug dependence are more complex, with treatment aims including reduction in use to the point that drug use no longer interferes with normal activities such as work and family commitments; shifting the addict away from more dangerous routes of drug administration such as injecting to safer routes such as oral administration; reduction in crime committed by drug addicts; and treatment of other comorbid conditions such as AIDS, hepatitis and mental health disorders. These kinds of outcomes can be achieved without eliminating drug use completely. Drug treatment programs in Europe often report more favorable outcomes than those in the US because the criteria for measuring success are functional rather than abstinence-based. The supporters of programs with total abstinence from drugs as a goal believe that enabling further drug use means prolonged drug use and risks an increase in addiction and complications from addiction.

"Substance dependence", as defined in the DSM, can be diagnosed with physiological dependence, evidence of tolerance or withdrawal, or without physiological dependence.

DSM-5 substance dependencies include:

- 303.90 Alcohol dependence

- 304.00 Opioid dependence

- 304.10 Sedative, hypnotic, or anxiolytic dependence (including benzodiazepine dependence and barbiturate dependence)

- 304.20 Cocaine dependence

- 304.30 Cannabis dependence

- 304.40 Amphetamine dependence (or amphetamine-like)

- 304.50 Hallucinogen dependence

- 304.60 Inhalant dependence

- 304.80 Polysubstance dependence

- 304.90 Phencyclidine (or phencyclidine-like) dependence

- 304.90 Other (or unknown) substance dependence

- 305.10 Nicotine dependence

Kim Janda has been working for years on a vaccination that would treat cocaine use disorders by limiting its rewarding effects.

Transcranial magnetic stimulation (TMS) is being studied as a treatment for cocaine addiction. So far studies have been undertaken by Medical University of South Carolina (MUSC), National Institute on Drug Abuse (NIDA), and Mexican National Institute of Psychiatry.

Therapists often classify patients with chemical dependencies as either interested or not interested in changing.

Treatments usually involve planning for specific ways to avoid the addictive stimulus, and therapeutic interventions intended to help a client learn healthier ways to find satisfaction. Clinical leaders in recent years have attempted to tailor intervention approaches to specific influences that affect addictive behavior, using therapeutic interviews in an effort to discover factors that led a person to embrace unhealthy, addictive sources of pleasure or relief from pain.

From the applied behavior analysis literature and the behavioral psychology literature, several evidenced-based intervention programs have emerged (1) behavioral marital therapy (2) community reinforcement approach (3) cue exposure therapy and (4) contingency management strategies. In addition, the same author suggests that social skills training adjunctive to inpatient treatment of alcohol dependence is probably efficacious.

It is common for individuals with drugs use disorder to have other psychological problems. The terms “dual diagnosis” or “co-occurring disorders,” refer to having a mental health and substance use disorder at the same time. According to the British Association for Psychopharmacology (BAP), “symptoms of psychiatric disorders such as depression, anxiety and psychosis are the rule rather than the exception in patients misusing drugs and/or alcohol.”

Individuals who have a comorbid psychological disorder often have a poor prognosis if either disorder is untreated. Historically most individuals with dual diagnosis either received treatment only for one of their disorders or they didn’t receive any treatment all. However, since the 1980s, there has been a push towards integrating mental health and addiction treatment. In this method, neither condition is considered primary and both are treated simultaneously by the same provider.

There are effective treatments for nicotine dependence, although the majority of the evidence focuses on treatments for cigarette smokers rather than people who use other forms of tobacco (e.g., chew, snus, pipes, hookah, electronic cigarettes). These treatments have been shown to double or even triple a smoker’s chances of quitting successfully.

There are approximately 976 million smokers in the world. Estimates are that half of smokers (and one-third of former smokers) are dependent based on DSM criteria, regardless of age, gender or country of origin, but this could be higher if different definitions of dependence were used. Recent data suggest that, in the United States, the rates of daily smoking and the number of cigarettes smoked per day are declining, suggesting a reduction in population-wide dependence among current smokers. However, there are different groups of people who are more likely to smoke than the average population, such as those with low education or low socio-economic status and those with mental illness. There is also evidence that among smokers, some subgroups may be more dependent than other groups. Men smoke at higher rates than do women and score higher on dependence indices; however, women may be less likely to be successful in quitting, suggesting that women may be more dependent by that criterion. Higher nicotine dependence has also been linked with mental illness, including anxiety and depression.

The symptoms of stimulant use disorder include failure to control usage and frequency of use, an intense craving for the drug, increased use over time to obtain the same effects, known as a developed tolerance, and a continued use despite negative repercussions and interference in one’s everyday life and functioning. Furthermore, a disorder is noted when withdrawal symptoms occur because of a decrease in the drug amount and frequency, as well as stopping the use of the drug entirely. These withdrawal symptoms can last for days, weeks, months, and on rare occasions, years, depending on the frequency and dosages used by the individual. These symptoms include, but are not limited to, increased appetite, decreased energy, depression, loss of motivation and interest in once pleasurable activities, anxiety, insomnia, agitation and an intense craving for the drug. Unless intensive medical and psychological treatment is sought after, there is a very high likelihood of relapse among the user.

Barbiturate dependence develops with regular use of barbiturates. This in turn may lead to a need for increasing doses of the drug to get the original desired pharmacological or therapeutic effect. Barbiturate use can lead to both addiction and physical dependence, and as such they have a high potential for abuse. Management of barbiturate dependence involves considering the affected person's age, comorbidity and the pharmacological pathways of barbiturates. Psychological addiction to barbiturates can develop quickly. The GABA receptor, one of barbiturates' main sites of action, is thought to play a pivotal role in the development of tolerance to and dependence on barbiturates, as well as the euphoric "high" that results from their abuse. The mechanism by which barbiturate tolerance develops is believed to be different from that of ethanol or benzodiazepines, even though these drugs have been shown to exhibit cross-tolerance with each other. The management of a physical dependence on barbiturates is stabilisation on the long-acting barbiturate phenobarbital followed by a gradual titration down of dose. The slowly eliminated phenobarbital lessens the severity of the withdrawal syndrome and reduces the chances of serious barbiturate withdrawal effects such as seizures. Antipsychotics are not recommended for barbiturate withdrawal (or other CNS depressant withdrawal states) especially clozapine, olanzapine or low potency phenothiazines e.g. chlorpromazine as they lower the seizure threshold and can worsen withdrawal effects; if used extreme caution is required.

The long-term abuse of stimulants ultimately causes very serious medical issues, including but not limited to, addiction. Addiction, which is a disease that causes high rates of relapse, can be defined as a chronic disease that is characterized as a compulsive drug seeking behavior in which the user will stop at nothing to obtain the drug. Long time users of stimulants have noted changes in the body such as brain function, chemistry and molecular or cellular adaptations.

Different assessment tools can be used to determine if an individual is addicted to exercise. Most tools used to determine risk for exercise addiction are modified tools that have been used for assessing other behavioral addictions. Tools for determining eating disorders can also show a high risk for exercise addiction.

The Obligatory Exercise Questionnaire was created by Thompson and Pasman in 1991, consisting of 20 questions on exercise habits and attitudes toward exercise and body image. Patients respond to statements on a scale of 1 (never) to 4 (always). This questionnaire aided in the development of another assessment tool, the Exercise Addiction Inventory.

The Exercise Addiction Inventory was developed by Terry "et al" in 2004. This inventory was developed as a self-report to examine an individual's beliefs toward exercise. The inventory is made up of six statements in relation to the perception of exercise, concerning: the importance of exercise to the individual, relationship conflicts due to exercise, how mood changes with exercise, the amount of time spent exercising, the outcome of missing a workout, and the effects of decreasing physical activity. Individuals are asked to rate each statement from 1 (strongly disagree) to 5 (strongly agree). If an individual scores above 24 they are said to be at-risk for exercise addiction.

A short 11-question Internet game screen called the BIGS was developed by reSTART to assist in the screening of problematic video game and Internet use.

Screening for problematic use in individuals due the ever-changing digital landscape. Researchers Northrup, Lapierre, Kirk and Rae developers of the Internet Process Addiction Test (IPAT) propose that tools measure different processes utilized over the Internet, such as video game play, social networking, sexual activity and web surfing, may be more helpful than a measure of Internet addiction itself, as the Internet is simply a medium which facilities a variety of interactions, some of which are highly addictive, and others less so.

Confirming the presence of withdrawal in the neonate can be assessed from obtained a detailed medical history from the mother. In some cases neonatal drug withdrawal can be mistaken for central nervous system disorders. Typically the tests that are ordered are CBC, hair analysis, drug screen (of mother and infant), thyroid levels, electrolytes, and blood glucose. Chest x-rays can confirm or infirm the presence of heart defects. The diagnosis for babies with signs of withdrawal may be confirmed with drug tests of the baby's urine or stool. The mother's urine will also be tested.

There are at least two different scoring systems for neonatal withdrawal syndrome. One difficulty with both is that were developed to assess opiate withdrawal. The Finnegan scoring system is more widely used.

The most common instrument used to screen for "probable pathological gambling" behavior is the South Oaks Gambling Screen (SOGS) developed by Lesieur and Blume (1987) at the South Oaks Hospital in New York City. In recent years the use of SOGS has declined due to a number of criticisms, including that it overestimates false positives (Battersby, Tolchard, Thomas & Esterman, 2002).

The "DSM-IV" diagnostic criteria presented as a checklist is an alternative to SOGS, it focuses on the psychological motivations underpinning problem gambling and was developed by the American Psychiatric Association. It consists of ten diagnostic criteria. One frequently used screening measure based upon the DSM-IV criteria is the National Opinion Research Center DSM Screen for Gambling Problems (NODS). The Canadian Problem Gambling Inventory (CPGI) and the Victorian Gambling Screen (VGS) are newer assessment measures. The Problem Gambling Severity Index, which focuses on the harms associated with problem gambling, is composed of nine items from the longer CPGI. The VGS is also harm based and includes 15 items. The VGS has proven validity and reliability in population studies as well as Adolescents and clinic gamblers.

In November 2016, the American Association of Sexuality Educators, Counselors and Therapists (AASECT), the official body for sex and relationship therapy in the United States, issued a position statement on Sex Addiction which states that AASECT "does not find sufficient empirical evidence to support the classification of sex addiction or porn addiction as a mental health disorder, and does not find the sexual addiction training and treatment methods and educational pedagogies to be adequately informed by accurate human sexuality knowledge. Therefore, it is the position of AASECT that linking problems related to sexual urges, thoughts or behaviors to a porn/sexual addiction process cannot be advanced by AASECT as a standard of practice for sexuality education delivery, counseling or therapy."

In 2017, three new USA sexual health organizations found no support for the idea that sex or adult films were addictive in their position statement.

In November 16, 2017 the Association for the Treatment of Sexual Abusers (ATSA) published a position against sending sex offenders to sex addiction treatment facilities. Those centers argued that "illegal" behaviors were symptoms of sex addiction, which ATSA challenged they had no scientific evidence to support.

In general, the simultaneous use of multiple drugs should be carefully monitored by a qualified individual such as board certified and licensed medical doctor, either an MD or DO Close association between prescribing physicians and pharmacies, along with the computerization of prescriptions and patients' medical histories, aim to avoid the occurrence of dangerous drug interactions. Lists of contraindications for a drug are usually provided with it, either in monographs, package inserts (accompanying prescribed medications), or in warning labels (for OTC drugs). CDI/MDI might also be avoided by physicians requiring their patients to return any unused prescriptions. Patients should ask their doctors and pharmacists if there are any interactions between the drugs they are taking.