Substance use disorder: Clinical sciences

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Introduction0:00–0:35

Substance use disorder is a medical condition characterized by the inability to control the consumption of a substance despite adverse health and social consequences.
The cause of substance use disorder is multifactorial and includes psychological, biological, social, and environmental factors.
Based on criteria defined in the Diagnostic and Statistical Manual of Mental Disorders, 5th edition, or DSM-5, you can categorize a substance use disorder as mild, moderate, or severe.

Unstable Patient0:35–1:38

Okay, if a patient presents with a chief concern suggesting a substance use disorder, first perform an ABCDE assessment to determine if the patient is unstable or stable.
If your patient is unstable, stabilize the airway, breathing, and circulation, which might require endotracheal intubation with mechanical ventilation.
Next, obtain IV access and put your patient on continuous vital sign monitoring, including blood pressure, heart rate, pulse oximetry, and cardiac telemetry.
Here’s a clinical pearl to keep in mind! Patients with substance use disorder might present with a few potentially unstable conditions.
For example, cocaine toxicity can cause cardiac ischemia and seizures, whereas heroin or other opioid toxicity can result in severe drowsiness, respiratory depression, and coma.
Benzodiazepine toxicity can also cause CNS depression, whereas benzodiazepine or alcohol withdrawal can cause potentially fatal seizures!

Stable Patient1:38–4:17

Now that we’ve addressed unstable patients, let’s return to the ABCDE assessment and take a look at stable patients. If the patient is stable, first obtain a focused history and physical exam.
Next, assess for substance use with a screening test, such as the Drug Abuse Screening Test, or DAST-10. DAST-10 contains ten “yes” and “no” questions about substance use over the past 12 months and includes illicit drugs, prescription medication and over-the-counter medication.
However, keep in mind that this screening test excludes alcohol use. Now, here’s a high-yield fact!
If you suspect your patient is using more than one substance, you might want to use the ASSIST questionnaire, which stands for Alcohol, Smoking, and Substance Involvement Screening Test.
This is an 8-question test that identifies misused substances, such as tobacco, alcohol, cannabis, cocaine, stimulants, inhalants, sedatives, hallucinogens, and opioids.
Next, your patient or their close contact may report concerns about their substance use, but keep in mind that some patients may conceal or minimize concerns related to substance use despite associated relationship struggles, such as strained friendships or difficulties with co-workers.
Sometimes, there might be a history of a mood or personality disorder, such as depression or borderline personality disorder, or a childhood trauma, such as parental abandonment.
Family history may reveal alcohol or other substance use disorders. Physical examination may reveal abnormal blood pressure, needle puncture marks on the skin, and damaged nasal septum.
Additionally, you may observe abnormal pupils, which could be either dilated or constricted depending on which substance is involved.
But, in some cases, your patient’s examination might be completely normal. Finally, if the DAST-10 score is 3 or higher, you should suspect a substance use disorder!
Here’s a clinical pearl! Different substances cause different signs and symptoms.
For example, acute toxicity from stimulants like amphetamine and cocaine cause hypertension, tachycardia, and dilated pupils.
On the other hand, CNS depressants, such as barbiturates and benzodiazepines, cause somnolence, slowed respiratory rate, hypotension, and pinpoint pupils.
Next, with cannabis use, look for conjunctival injection; while those using phencyclidine might present with nystagmus. Okay, once you suspect a substance use disorder, assess the DSM-5 criteria for substance use disorder.

DSM-5 Criteria4:17–6:14

The DSM-5 lists eleven criteria that fall into four general categories including impaired control, physical dependence, social problems, and risky use.
First, let’s discuss factors suggesting impaired control, like if your patient is consuming more substances than intended or for a longer duration than intended.
Next, they might be spending more time obtaining, consuming, or recovering from substances; or they continue to use substances despite insight into the problem, like after legal consequences.
Next up is physical dependence, like if they report cravings for substances; have unsuccessful attempts to decrease or stop using them; or even develop withdrawal symptoms, such as tremor or restlessness.
Additionally, over time, your patient could develop tolerance to a specific substance, which means they have to take more of it to reach the desired effect.
Here’s a clinical pearl! The development of tolerance to a substance alone does not necessarily indicate the presence of a substance use disorder.
Keep in mind that tolerance can develop in patients who are prescribed appropriate doses of medications as directed, such as benzodiazepines for anxiety disorder or opioids for chronic pain!
Now, social problems are apparent if your patient has reduced or given up important daily activities, like their favorite hobby or even personal hygiene.
Other important social problems include failing to fulfill major obligations, such as work-related or parenting responsibilities; or continuing to consume substances despite these social and interpersonal problems.
Finally, your patient might participate in risky use, consuming substances in physically hazardous situations, like while operating a motor vehicle, using substances while another person is under their care, or drinking on the job.
Now, if your patient meets two or more of these 11 criteria in the last 12 months, diagnose a substance use disorder! Usually, the diagnosis of substance use disorder is qualified by the specific substance used, such as cocaine use disorder or marijuana use disorder.

Assess severity6:14–7:00

But keep in mind that individuals meeting criteria for one substance could be using other substances as well. One big issue with substance use disorders, especially when the substance is illegal, is that individuals might end up using more substances than they intended.
As an example, cocaine is often contaminated with fentanyl. So, someone with cocaine use disorder, not looking for opioids, could end up facing an opioid overdose.
Okay, once you diagnose a specific substance use disorder, assess the severity based on the number of criteria that are met.

Mild SUD7:00–8:02

If your patient meets two or three of the DSM-5 criteria, diagnose mild substance use disorder. The first step in management is counseling in the form of a brief intervention, usually during a routine outpatient encounter.
You should use motivational interviewing techniques, like asking open-ended questions, which helps patients develop insight into the effects of their substance use.
Patients with mild substance use disorder may also benefit from individual or group counseling. Commonly used techniques include cognitive-behavioral therapy, or CBT, with additional support from peer recovery groups, such as Alcoholics Anonymous or AA, Narcotics Anonymous or NA, and Cocaine Anonymous or CA.
Individuals in this category may also benefit from pharmacotherapy, if it’s available for their substance. Finally, don’t forget to treat associated medical conditions, such as hypertension or mood disorders.

Moderate SUD8:02–8:45

Next, if your patient meets four or five of the DSM-5 criteria, diagnose moderate substance use disorder. Again, these patients will benefit from counseling, either in an individual or group setting, and they might benefit from treatment programs, in an inpatient or outpatient setting.
Individuals may also benefit from pharmacotherapy, if it’s available for their substance. Again, don’t forget to treat associated medical conditions!
Here’s a high-yield fact! Although pharmacologic treatments are used to help patients achieve success and prevent relapse with alcohol and opioid use disorders, they’re not routinely used with other common substance disorders.
Finally, if your patient meets six or more of the DSM-5 criteria, diagnose a severe substance use disorder. Similar to patients with mild and moderate substance use disorder, these patients will benefit from counseling, a treatment program, pharmacotherapy if it’s available for their substance, and the treatment of any associated conditions!

Severe SUD8:45–9:04

Review9:04–9:44

Alright, as a quick recap… Substance use disorders are characterized by an impaired ability to control the consumption of a substance despite adverse health and social consequences.
The first step is to perform a thorough history including a validated substance screening test, such as DAST-10. If the screening test is positive and the patient meets two or more criteria of the DSM-5 criteria, diagnose a substance use disorder.
All individuals with a substance use disorder will benefit from counseling and the treatment of associated conditions. Patients may also benefit from inpatient or outpatient substance use treatment programs if their substance use disorder is