Substance Use Disorders

sec_arr Appendix C


C-1: Introduction

Individuals who have used illegal drugs in the past, but are not current users, may be covered by the Americans with Disabilities Act (ADA)14; however, current illicit drug users and those who misuse alcohol in violation of company policy may not be protected under ADA. Current medical guidelines exist for physician evaluation of fitness for duty following a diagnosis of substance use disorders, including commercial driving,15,16 railway work,17 and commercial aviation.18 It is common occupational medical practice in evaluation of fitness for duty in safety-sensitive work that the individual be referred for a comprehensive evaluation if diagnostic criteria are met or suspected for substance abuse or dependence.19

In law enforcement work, perceived work stress is significantly associated with increased risk of alcohol abuse with an odds ratio of 3.20 LEOs may consume alcohol in far greater quantities, have high rates of binge drinking (especially those age 18 to 25) compared to non-LEOs, and 25% of officers reported having consumed alcohol while on duty.21

In a sample of police officers, 18% of male officers and 16% of female officers described adverse consequences from alcohol use, with approximately 11% of males and 16% of females engaged in at-risk levels of alcohol use during the previous week. In addition, more than one-third of male and female officers reported binge drinking during the previous month and 7.8% of officers likely had met criteria for alcohol abuse or dependence at some time in their lives.22

Alcohol and drug use patterns include:

  • Use without problems;
  • Use with resultant problems or health risk;
  • Use with recurrent or serious consequences meeting DSM-IV-TR criteria for abuse;
  • Use meeting DSM-IV-TR criteria for dependence.23

C-2: Substances

A substance is defined as any drug with psychoactive qualities. Ten categories as reflected in the DSM-5 include: alcohol, caffeine, cannabinoids (marijuana), hallucinogens (with separate categories for phencyclidine or similarly acting arylcyclohexylamines and other hallucinogens), inhalants, opioids, sedatives, hypnotics and anxiolytics, stimulants, tobacco (nicotine), and other (or unknown) substances. Nicotine and caffeine are listed as substances in the DSM-5. Nicotine use can meet DSM-IV-TR criteria for substance dependence, but this condition is not addressed in this fitness-to-work guide as nicotine, despite the long-term adverse consequences of smoking, is not known to generally impair the ability of the LEO to perform essential job tasks. In addition, any symptoms of craving or withdrawal can be reasonably managed with nicotine replacement therapies.

The following describes some commonly used substances and their effects on the user:

A standard drink as defined by the National Institute on Alcohol Abuse and Alcoholism (NIAAA), is any drink that contains about 14 grams of pure alcohol (about 0.6 fluid ounces or 1.2 tablespoons) and this is approximately equivalent to 12 oz. of beer, 5 oz. of wine, and 1.5 oz. of spirits.24 The NIAAA maximum daily drinking limit for women is a maximum of 3 drinks on any day, and up to and including 7 drinks per week. For men, it is 4 drinks any day, and up to and including 14 drinks per week.25(p381) Above these limits, alcohol use is associated with multiple co-morbid conditions including heart disease, hypertension, stroke, cancers, and liver cirrhosis, among other disorders. Alcohol use disorders are associated with concurrent psychiatric conditions including depressive episodes, severe anxiety, insomnia, suicide, and abuse of other substances.

In the U.S. Armed Forces, service members who are heavy drinkers (defined as 5 or more drinks on one occasion at least once per week) are more at risk for work-related lateness, leaving early, decreased performance, and injuries than non- or light drinkers.19 A blood alcohol level of 50 mg/100 mL or above indicates unfitness for duty in the Armed Forces.3(p528) Tracking, visual vigilance, divided attention, postural stability, and cancellation tasks as well as memory, judgment, and other cognitive tasks are affected by alcohol.4 Alertness, judgment, decision making, divided attention, and motor performance can be impaired even at low blood alcohol levels of 0.02% blood alcohol concentration (equivalent to 1 drink for a person weighing 150 pounds.4(p846) Degradation in task performance can still be measured 4 to 8 hours after reaching peak blood alcohol levels and “hangover” effects can affect work performance.4(p839)

Cannabis (marijuana) use is associated with impaired cognition during acute intoxication as well as in the unintoxicated state in long-term users, especially in the domains of verbal learning, memory, and attention.26 A single “joint” of cannabis can generally cause measurable impairment in skills for more than 10 hours.3(p529) In flight simulator trials, significant errors occur up to 24 hours post marijuana inhalation with the cognitive impairments lasting well after the awareness of euphoria has disappeared.27 Moderate continued cannabis use is associated with selective short-term memory deficits that persist following a period of several weeks of abstinence.3(p529) Irrespective of the source (e.g. medicinal, medical, or otherwise) or context (licit or illicit) marijuana is impairing.

Stimulants (Cocaine and Amphetamines):
These cause a large outflow of stimulating neurotransmitters, e.g., dopamine and epinephrine, in the nervous system and the brain. Epinephrine (a.k.a., adrenaline) is the neurotransmitter associated with the sympathetic nervous system and the “fight or flight” response. Being under the influence of stimulants like cocaine or amphetamines mimics being in an ongoing fight-or-flight response. The body and the mind are substantially “amped” up. Agitation, irritability, impulsivity, and impaired judgment are common. Stimulants are some of the most highly addictive classes of substances known.

  • Cocaine:
    Recreational cocaine users can display numerous performance deficits involving executive functioning deficits. Protracted heavy cocaine use can result in depressive symptoms, persistent cognitive impairment in areas such as executive function, visual perception, psychomotor speed, dexterity, attention, and planning persisting for at least 4 weeks after abstaining.28 Disturbances in sleep associated with chronic cocaine use are thought to contribute to abstinence-related cognitive dysfunction.29
  • Amphetamines:
    Complications include ischemic strokes and rhabdomyolysis, among others.30 As with cocaine, chronic amphetamine abuse is associated with cognitive impairment, which may persist for several months after beginning abstinence.25(p161)

An acute withdrawal syndrome is recognized; however, the existence of a prolonged withdrawal syndrome is debated.25(p127) Individuals with alcohol dependence are at risk for benzodiazepine abuse.25(p125)

Some individuals with opioid dependence may have a degree of cognitive impairment persisting during early abstinence.31 Opioid analgesics can be improperly used, and widespread use has resulted in a national epidemic of opioid overdose deaths and addictions.32

Anabolic Androgenic Steroids:
Approximately 80% of athletes reporting anabolic androgenic steroids use self-administered intra-muscular injections.33 Adverse effects include multiple endocrine, cardiovascular and neurological side effects and increased risk of physical training injuries, although most effects resolve within 3 months of discontinuation (although as AAS users age, potentially long-lasting organ damage may have occurred that may accelerate the deterioration that occurs during the normal aging process).25(p282) Prolonged use may result in hypomania and even psychotic symptoms, and withdrawal may precipitate craving for more steroids and symptoms of fatigue, depression, restlessness, insomnia or anorexia, among others.25(p284-5) Some individuals may meet the criteria for dependence,34 and therefore are at risk for relapse after discontinuation. Law enforcement officers have been reported to take these drugs.34 Many anabolic-androgenic steroid users also abuse other accessory drugs including amphetamines, ephedrine, thyroxine, and growth hormone. The potential adverse effects of some accessory drugs may be more serious than those of anabolic androgenic steroids.25(p284-5)

C-3: User Denial of Substance Use Problem

Denial, a psychological defense mechanism, is not specific to substance use disorders. Patients with other chronic medical disorders will under-report unhealthy behaviors to caregivers.25(p295) Research suggests that concealing substance use is common. Both stigma and sanctions may influence self-reporting as substance use or its consequences can be purposely minimized due to desire to avoid unwanted consequences (e.g., work suspension) or unwillingness to accept responsibility for ensuing behavior (e.g., impairment while at work).37 Clinical assessors should attempt to detect an individual’s use of substances despite denial and be familiar with interview techniques to facilitate this process.38

Denial is considered a consistent clinical component of alcohol dependence and includes “the pharmacologic effects of alcohol on memory, the influence of euphoric recall on perception and insight, the role of suppression and repression as psychological defense mechanisms, and the impact of social and cultural enabling behavior.”39

Denial related to dependence can be due to cerebral dysfunction rather than a psychodynamic defense. Notably, denial in alcoholism is associated with alcohol-related cognitive impairment of executive function, verbal memory, visual inference, and mental speed.40

C-4: Comorbidity

Substance Use Disorder Comorbidity and Chronic Impairment:

Comprehensive substance use disorder evaluation of LEOs must fully consider the possibility of related medical and/or psychiatric comorbidity. The comorbid conditions likely will warrant further evaluation and treatment. Complications of substance use disorders are associated with increased risk for impairment. The comorbid conditions may themselves be contra-indications to return to full police duties.

The components of screening for substance use disorder comorbidity include comprehensive screening for other psychiatric disorders, whether DSM-IV-TR or DSM-5 (e.g., major depression with suicide screening, bipolar mood disorder, or anxiety disorders including panic disorder). Various clinical screening items exist – for major depression, the Patient Health Questionnaire-9 (PHQ-9); for generalized anxiety disorder, the GAD-7; and for panic disorder, question “C” of the PHQ-SADS. (These three screening questionnaires are all available at The screening questionnaire for post-traumatic stress disorder is the PCL-5 (available at no charge from

  • Screening for drug- and/or alcohol-related conditions such as gastric ulcers, pancreatitis, chronic anemia, hepatitis B and C, cirrhosis, HIV, myopathy, hypertension, seizures, or Wernicke’s encephalopathy with a complete physical examination, including a thorough neurological screening examination.
  • A detailed mental status examination (MSE), including basic neuro-psychological cognitive screening such as the Montreal Cognitive Assessment (MoCA). This free site requires registration.
  • Clinical laboratory investigations such as CBC, liver enzymes, or imaging investigations (e.g., CT of the head for alcohol-related cerebral atrophy) as appropriate for established comorbid conditions related to use of that substance.

Substance-dependent individuals with central nervous system damage due to chronic substance use such as Wernicke’s encephalopathy or alcohol-related cerebellar dysfunction will likely require permanent restrictions from return to LEO duties.

Select comorbid conditions may be addressed in the relevant sections of this document – e.g., cardiovascular conditions that may be related to excessive alcohol use such as hypertension, atrial fibrillation and cardiomyopathy (see LEO chapter on Cardiolovascular Disease).

Any impairing substance-related co-morbidity should be treated and controlled before returning to work.40 Therefore, clinicians conducting comprehensive substance use disorder evaluations of LEOs must be highly vigilant for the possibility of comorbidity.41 For example, chronic heavy alcohol consumption can cause peripheral neuropathy, gastrointestinal disorders, abnormal blood cell production, mild anterograde amnesias, other cognitive deficits, and significant sleep problems.43 In approximately 25% of “lone” atrial fibrillation or flutter cases requiring hospitalization, alcohol or illicit drugs were the precipitating cause.44

Alcohol has also been found to induce obstructive sleep apnea (OSA) in healthy, asymptomatic persons as well as persons who chronically snorer.15(p1222) Substance use may also worsen existing severe OSA. In patients with established OSA (see sleep disorders section), the consumption of 2 or more drinks of alcohol per day is associated with a 5-fold increase in fatigue-related motor vehicle collisions.25(p1222)

Alcohol may cause clinically significant hypoglycemia.25(p1239) There are multiple pathophysiological paths of alcohol-induced hypoglycemia (see Inparing Events in the Diabetes Mellitus chapter) and alcohol-induced reactive hypoglycemia.25(p1239)

Of those individuals with an alcohol use disorder, up to 37% have a concurrent psychiatric disorder.45 Post-traumatic stress disorder (PTSD) is a common comorbid condition in military personnel usually requiring more intensive addiction services.19 The National Comorbidity Survey found that individuals with PTSD were 2 to 4 times more likely to meet criteria for a substance use disorder.25(p1404)

C-5: Treatment

In safety-sensitive work, a diagnosis generally warrants outpatient treatment, although individuals considered at increased risk (multiple alcohol incidents and severe psychosocial problems) could be placed in a more intensive level of treatment. A diagnosis of alcohol dependence warrants intensive outpatient treatment, day treatment, or residential treatment.19 It may also warrant detoxification services prior to admission to an appropriate program. Although research is mixed, some studies point to better outcomes with residential treatment,46 especially those with more serious employment problems such as performance or attendance concerns.25(p420) It is notable that 78% of substance use impaired physicians receive residential treatment for 30 to 90 days.25(p611) LEOs, like other safety-sensitive workers, do best when offered cohort-specific treatment, which facilitates adequate self-disclosure and the subsequent repair of the damage produced by past substance-related behaviors.47 Police officers, especially those in undercover drug operations, have easy access to gray and black market drugs. The treatment of such individuals should include management of drug access, drug refusal skills, work environment modification to decrease drug access, and other occupation-specific interventions geared to decrease relapse.34(p1253-63)

Containing alcohol and other drug use and sequestering the safety sensitive worker away from work may mandate a more intensive level of initial care than with the general public. Treatment of a safety sensitive worker may require Level 3 care (As defined by ASAM, ranging from clinically managed low-intensity residential services to medically monitored intensive inpatient services). Specialized substance use treatment cohorts are available for police and fire fighters to go through treatment with others who have comparable workplace experiences.34(p1253-63)

C-6: Risk of Substance Use Relapse

All LEOs with a diagnosis of a substance use disorder should be thoroughly assessed for relapse risk before returning to duties. When a substance use disorder has been diagnosed, consideration should be given to a clinical monitoring programs (which usually includes random alcohol and drug testing), mandated employee assistance or impaired professional programs.41(p100)

Approximately 40% to 60% of discharged substance dependent patients remain abstinent 1 year post-treatment. This is comparable to rates of symptom recurrence of other chronic diseases such as type-2 diabetes and asthma.48 However, up to 70% of professional employees successfully return to work with definitive treatment and subsequent monitoring.49 A period of documented abstinence (which includes sobriety from alcohol) is required following treatment and before a return to safety sensitive work as there is a higher risk of relapse in the period immediately following treatment.49

Even one episode of relapse is a poor prognostic indicator. An initial relapse after a diagnosis of substance dependency has a hazard ratio of 1.7 for a subsequent relapse.49 A family history of a substance use disorder, abuse of a major opioid (such as meperidine hydrochloride, morphine, fentanyl, methadone hydrochloride, heroin, or controlled-release oxycodone hydrochloride) and a concurrent psychiatric disorder are all individually significant relapse risk factors. The presence of all three risk factors has a cumulative hazard ratio of 13.25 for relapse.49 Treatment non-completion is a significant risk factor for relapse. One study shows an odds ratio of 6.5 for relapse as compared to those with successful treatment completion.50 At 3 months post-treatment, mild to moderate depressed individuals were, on average, 2.9 times more likely to eventually relapse to alcohol. Those severely depressed were 4.9 times more likely to relapse.51 Anxiety disorders, especially social anxiety disorder and panic disorder, are also risks for relapse to alcohol.52

Evaluation and treatment for insomnia is an often overlooked aspect of both substance use disorder treatment and relapse risk evaluation.42(p92) At the 5-month mark of alcohol abstinence, prolonged sleep latency and poor sleep efficiency are predictors of relapse by 1 year.25 Abstaining individuals who begin to drink alcohol again will experience an increase in total sleep time and reduction in sleep fragmentation. This initial perceived positive effect of nighttime alcohol use likely contributes to relapse even though continued alcohol use will further disrupt sleep.25(p1221-2) Cognitive behavioral approaches such as sleep hygiene instructions and stimulus control should be included in a substance use disorder treatment plan regardless of the use of pharmacotherapy to assist sleep53 (see LEO Medications chapter for recommendations regarding sedative, hypnotic, and anxiolytic medications). Evaluation and treatment regarding coping skills is an essential part of relapse evaluation and prevention as coping style is a significant predictor of relapse.25(p997)

C-7: Clinical Monitoring

Clinical monitoring is described in the American Society of Addiction Medicine’s (ASAM’s) most recent definitive text as “not only justifiable, but good medicine.”25(p616) As with the treatment of other medical disorders such as asthma or diabetes, clinical monitoring improves clinical outcomes. Due to limitations of self-reporting with substance use disorders, addiction specialist physicians frequently perform clinical drug testing. When used in concert with a history, physical examination and laboratory result, clinical drug testing improves the medical care of an individual.

Substance use relapses are often detected by workplace monitoring. Monitoring is usually required in return-to-work planning in safety sensitive positions.26(p535) Successful programs include random alcohol and drug testing via an ongoing monitoring program. For physicians, these commonly taper in frequency over a period of 5 years.25(p613) Monitoring components can include regularly scheduled face-to-face visits with a clinician providing support, screening for impending relapse, reviewing compliance with treatment, and testing breath and body fluids in order to verify abstinence. For most safety-sensitive positions, monitoring typically includes 24 unannounced tests/monitoring sessions over 2 years, based on the substance use disorder and a consulting physician’s input. Monitoring dates should be unpredictable. A certified medical review officer (MRO) should interpret drug testing results.

C-8: Chronic Impairment with Substance Abstinence

Recovery and continued abstinence usually results in improvement of substance-related impairment. However, with protracted and heavy use of substances, longstanding or even permanent impairment may result (e.g., cognitive impairment). Cortical atrophy can occur in those individuals with alcohol dependence.54

Long-term adverse medical effects of cocaine include cardiac ischemia, myocardial infarction, stroke, and cognitive impairment.32 Cognitive impairment may persist despite several months of abstinence and sobriety. The most affected cognitive attributes are visual-motor performance, attention, inhibitory control, and verbal memory. Several studies have found abnormalities of behavioral regulation and risk-reward decision-making54 (for cognitive screening test example, see Appendix F). The Montreal Cognitive Assessment (MoCA) may be used in identifying potential cognitive impairment among substance use disorder patients. Using a cut-point score of 25, the sensitivity for substance use disorder is 83% and specificity is 73%.55 Even in situations where the MoCA test is normal, there may exist subtler cognitive impairments, which may translate into capacity impairment or increased risk in LEO duties. Need for more extensive cognitive testing: Neuropsychological testing should be performed in almost every case. Such testing should be done by a qualified (e.g., board certified) Neuropsychologist who can determine how the results of a substance use disorder impact the safety of work.

Following treatment, and a period of abstinence, there may occur a situation where the LEO may present well in an interview with a normal mental status examination and a normal MoCA test result, however there may exist subtler unrecognized cognitive impairments (see Section on Suspicion of Substance Abuse) where it states for example: worsening performance, unreliability in someone previously reliable, and the inability to concentrate). Amongst other types of potential psychological impairments, the individual may not have the sufficient cognitive capacity for adaptation, a psychological attribute comparable to resilience which is critical for performing LEO duties. An impairment in adaptation is defined as “deterioration or decompensation in a complex work-like setting and stressful circumstances.”56(p362) They may perform poorly, withdraw from the situation or experience a relapse of the mental disorder, including a substance use disorder.

If the clinician has a high suspicion of cognitive impairment despite reasonable evidence of abstinence for at least a month, further assessment is warranted. This can take place in one of two pathways, assessment of performance while participating high cognitive demand job simulations or neuropsychological evaluation.

Performance testing for high cognitive demand duties may be a reasonable initial substitution for neuropsychological testing. Ideally this is department-based and includes job-simulation. Example of venues that the LEO could be required to pass include

  • Scenario-based decision-making
  • Firearms use testing
  • Use of force demonstration

Should the identified LEO not be able to successful pass the high cognitive response scenarios then a neuropsychological evaluation could be considered to distinguish between medical and nonmedical causes such as poor effort. The questions to the neuropsychologist should be ideally framed in a way that assists in the overall (fitness-for-duty assessment). Asking specifically about areas of psychological impairment such as concentration or memory, limitations and restrictions and, in addition providing a comprehensive job description or a cognitive demand analysis may assist with the clarity of the ensuing report. Such testing should be done by a seasoned Neuropsychologist who can determine how the results of a substance use disorder impact the safety of work.