Substance use disorder is diagnosed by matching a person’s pattern of substance use against a set of 11 behavioral and physical criteria. A clinician, typically a psychiatrist, psychologist, or addiction specialist, conducts an in-depth interview, reviews medical history, and may use screening questionnaires and lab tests to build a complete picture. There is no single blood test or brain scan that confirms the diagnosis on its own.
The 11 Diagnostic Criteria
The standard framework used in the United States comes from the DSM-5-TR, the current edition of the diagnostic manual used by mental health professionals. It lists 11 criteria grouped into four categories. A person needs to meet at least two of these within a 12-month period to receive a diagnosis.
Impaired Control (Criteria 1 Through 4)
- Using more than intended. Taking a substance in larger amounts or over a longer stretch of time than you originally planned.
- Wanting to cut back but failing. A persistent desire to reduce or stop use, often with unsuccessful past attempts.
- Time consumed by use. Spending a significant portion of the day obtaining, using, or recovering from the substance.
- Cravings. A strong, pressing urge to use the substance that can strike even during periods of relative stability.
Social Impairment (Criteria 5 Through 7)
- Failing obligations. Substance use interferes with responsibilities at work, school, or home.
- Relationship damage. Continuing to use despite ongoing social or interpersonal problems directly caused or worsened by the substance.
- Giving up activities. Dropping or pulling back from hobbies, social events, or professional opportunities because of use.
Risky Use (Criteria 8 and 9)
- Physically hazardous situations. Using the substance in settings where it creates real danger, like driving or operating machinery.
- Use despite known harm. Continuing use even when you’re aware it’s causing or worsening a physical or psychological problem.
Pharmacologic Signs (Criteria 10 and 11)
- Tolerance. Needing increasingly higher doses to get the same effect, or finding that the usual amount does noticeably less.
- Withdrawal. Experiencing a predictable set of physical and psychological symptoms when blood levels of the substance drop. These symptoms vary widely by substance.
One important detail: tolerance and withdrawal alone do not automatically mean someone has a substance use disorder. People taking prescribed medications under medical supervision can develop both without meeting the broader behavioral criteria.
How Severity Is Classified
The number of criteria a person meets determines whether the diagnosis is classified as mild, moderate, or severe. Meeting 2 to 3 criteria is considered mild. Four to 5 criteria is moderate. Six or more is severe. This matters because severity guides treatment recommendations. Someone with a mild alcohol use disorder might benefit from outpatient counseling, while someone meeting eight or nine criteria may need more intensive support.
What the Clinical Interview Looks Like
The core of the diagnostic process is a structured or semi-structured clinical interview. The most widely used version is the Structured Clinical Interview for DSM-5 (SCID-5), which walks through each diagnostic category systematically. It typically takes between 45 and 90 minutes and requires a clinician with training in psychopathology and diagnostic criteria, since professional judgment is needed to interpret the answers rather than simply tallying scores.
The process usually involves several steps: an initial interview with the patient, a review of their history including any past treatments or psychiatric diagnoses, conversations with family members when possible, and a final assessment by a supervising clinician. The goal is to understand not just current use but the lifetime course of the problem, how it has evolved, and how it intersects with other parts of the person’s life.
Clinicians often ask detailed questions about quantities, frequency, situations where use occurs, past quit attempts, and the consequences that have followed. They’re listening for the specific patterns described in the 11 criteria, but also for context that helps distinguish substance use disorder from other conditions that can look similar.
Screening Tools That Start the Process
Before a full diagnostic interview, many healthcare settings use brief screening questionnaires to identify people who may need further evaluation. These are not diagnostic on their own but serve as a first filter. The Drug Abuse Screening Test (DAST-10) is a widely used 10-item questionnaire that flags problematic drug use. The TAPS tool (Tobacco, Alcohol, Prescription medication, and other Substance use) covers a broader range of substances and can be filled out by the patient or administered by a clinician.
For adolescents, tools like the CRAFFT questionnaire are tailored to younger populations. The NIAAA also publishes a practitioner’s guide specifically for screening alcohol use in youth. Most of these tools take only a few minutes and can be self-administered in a waiting room or completed during a routine checkup. A positive screen doesn’t mean you have a substance use disorder. It means a more thorough evaluation is warranted.
The Role of Physical Exams and Lab Tests
Lab tests play a supporting role rather than a central one. Urine drug screens, the most common type, provide only qualitative results: positive or negative for a given substance. They cannot tell a clinician how much someone used, how often, or whether use has become disordered. Some substances or their byproducts remain detectable in urine long after intoxication has resolved, producing true positives that have no bearing on current clinical status. Serum (blood) testing is more precise and provides actual concentration levels, but it’s typically reserved for acute situations like suspected overdose rather than routine diagnosis.
A physical exam, on the other hand, can reveal telling signs. Clinicians look for pinpoint pupils (common with opioid use), dilated pupils, bloodshot eyes (associated with cannabis), slurred speech, unsteady gait, or unusual sweating. Track marks, scarring along veins, point to injection drug use. Burns on the hands, fingers, or lips can indicate pipe use, particularly with methamphetamine. Severe tooth decay or worn-down teeth suggest stimulant use, since drugs like amphetamines cause intense teeth grinding and jaw clenching.
Other findings are more subtle. Damage to the nasal lining may signal long-term cocaine use. A rash around the nose and mouth, sometimes called a “glue-sniffer’s rash,” is associated with inhalant use. Changes in grooming, significant weight loss or gain, and unexplained injuries like scrapes or bruising can all raise concern. Clinicians also listen to the heart and lungs, since injection drug use raises the risk of heart valve infections, and chronic alcohol use can lead to aspiration pneumonia. A brief cognitive evaluation can reveal memory problems tied to long-term alcohol, sedative, or inhalant use.
None of these findings alone confirm a diagnosis. They add supporting evidence to what the interview reveals.
Ruling Out Other Conditions
A careful diagnosis requires ruling out other explanations for the symptoms a person presents with. Virtually any psychiatric presentation, from depression to psychosis, can be caused by substance use, but the reverse is also true: psychiatric conditions can drive behaviors that look like substance use disorder.
Clinicians work through a structured process. First, they consider whether the person might be exaggerating or fabricating symptoms for an external reason, like avoiding legal consequences or obtaining specific medications. Next, they evaluate whether the psychiatric symptoms are actually a direct effect of the substance on the brain rather than a separate disorder. Depression during alcohol withdrawal, for example, may resolve on its own once the person stops drinking, which would change the diagnostic picture considerably.
Medical conditions also need consideration. Thyroid dysfunction can produce symptoms that mimic depression, and certain neurological conditions can affect behavior and cognition in ways that overlap with substance-related problems. The clinical question is always whether the substance use and the psychiatric or medical symptoms are independent, whether one is causing the other, or whether they’re truly co-occurring and need parallel treatment.
How International Criteria Differ
Outside the United States, many countries use the ICD-11, published by the World Health Organization. The ICD-11 takes a slightly different approach: it condenses its criteria into three paired categories, and a person needs to meet at least two of the three pairs to be diagnosed with substance dependence. In the largest multinational comparison study spanning 10 countries, alcohol dependence was diagnosed roughly 10% more often under ICD-11 rules than under the previous ICD-10 system. This means the threshold is somewhat more inclusive, and a person who doesn’t quite meet DSM-5 criteria could still qualify under international standards.
For most people seeking help in the U.S., the DSM-5-TR criteria are what their clinician will use. But the existence of two overlapping systems is worth knowing if you’re comparing diagnoses across countries or reading international research.