Laboratory tests are recommended primarily to corroborate the results of alcohol screening and interviews (NIAAA 2002a). For patients who are in treatment, lab tests can also be useful in motivating them and monitoring success (NIAAA 2007). Some research has indicated that combining lab tests can improve sensitivity and specificity (Anton et al. 2002, Brinkmann et al. 2000), but further research is needed. The most common clinical laboratory tests for detecting and monitoring alcohol use are:

GGT (gamma-glutamyl transferase) Heavy alcohol use (4 or more drinks per day for at least 4 weeks) can raise GGT levels significantly, and it takes 4 to 5 weeks of abstinence before blood protein levels return to normal (NIAAA 2002a). This test is not recommended for routine screening because it cannot discriminate between the different causes of liver damage (NIAAA 2002a), and it has relatively low sensitivity for detecting problem drinking that falls short of dependence (30% sensitivity for problem drinkers) (Warner 2003).
MCV (mean corpuscular volume)

The MCV test measures red blood cell size, which can increase after several weeks of chronic drinking. It may take up to 3 months of abstinence to see improvement in this measure, so it is less useful for monitoring treatment (Warner 2003). It has greater specificity than the GGT (fewer false positives); but according to the NIAAA (2002a), its sensitivity is too low for it to be used by itself to screen for problem drinking.
CDT (carbohydrate deficient transferrin)
The CDT test, which measures the amount of the carbohydrate-deficient form of transferrin, received FDA approval in 2000. Compared with other biomarkers, the CDT test results in fewer false positives (i.e., higher specificity). It also can indicate heavy alcohol use much earlier than either the GGT or the MCV (i.e., after only 1 to 2 weeks of heavy drinking) (NIAAA 2002a). The test is also useful in monitoring abstinence because it has a half-life of approximately 15 days (Warner 2003). It should be noted, however, that the CDT is less sensitive in women and adolescents (Anton et al. 2002, NIAAA 2002a).
View ReferencesHide References
Anton RF, Leiber C, Tabakoff B, and the CDTect Study Group. Carbohydrate-deficient transferrin and gamma-glutamyltransferase for the detection and monitoring of alcohol use: results from a multisite study. Alcoholism: Clinical and Experimental Research. 2002; 26(8): 1215-1222.
Brinkmann B, Kohler H, Banaschak S. ROC analysis of alcoholism markers - 100% specificity. International Journal of Legal Medicine. 2000; 113: 293.
National Institute on Alcohol Abuse and Alcoholism (NIAAA). Alcohol Alert No. 56: Screening for Alcohol Use Problems -- An Update. NIAAA Website. 2002a. Available at: Accessed on: 2010-10-28.
National Institute on Alcohol Abuse and Alcoholism (NIAAA). Helping Patients Who Drink Too Much: A Clinician's Guide, Updated 2005 Edition. Bethesda, MD. 2007. Available at: Accessed on: 2010-10-28.
Warner EA. Principles of Addiction Medicine. In: Graham AW, Schultz TK, Mayo-Smith MF, Ries RK, Wilford BB, eds. Principles of Addiction Medicine, Third Edition. Chevy Chase, Md: American Society of Addiction Medicine. 2003.
Difficulties in Diagnosing

Many symptoms of alcohol use disorders, intoxication, and withdrawal are similar to the symptoms of other health problems (Healthcommunities 2001). As a result, the following should be ruled out before diagnosing a patient:

  • brain trauma
  • hypoglycemia
  • electrolyte imbalance
  • diabetic acidosis and ketoacidosis
  • meningitis
  • neurological conditions (such as multiple sclerosis)
  • pneumonia
  • stroke
View ReferencesHide References Alcohol abuse. MentalHealthChannel. 4/3/2001. Available at: Accessed on: 2008-10-10.

You suspect gastritis and Tommy engages in an activity that is known to cause this disorder--excessive drinking (MayoClinic 2007). Reduction of alcohol use will help in confirming the diagnosis.

Doctor: Since the antacids didn't make you feel better, I'm going to prescribe some acid blockers to help reduce the acid in your stomach.
Tommy: You think that'll fix it?
Doctor: If the issue persists, we may have to move onto more aggressive treatment, but we're not at that level yet.
Tommy: Cool, so problem solved.
Doctor: Unfortunately, the alcohol you drink is irritating your stomach lining and may be causing bleeding and irritation. I'm recommending that you cut down on your alcohol use, with the goal of eventually abstaining from alcohol. I realize this may be difficult for you, but I would like for you to try this for one month when you return for a check-up.
Tommy: Look, doc, I understand where you're coming from. But like I told you, I can't just stop drinking.
Doctor: It would be better for your health if you eliminated alcohol entirely. If you feel like this is a step you aren't ready to take, I urge you to cut back your use as a stepping stone to complete abstinence.
Tommy: I can stop doubling up in the week, but that's about it.
Doctor: Let's draw up a clear statement of how much you are currently using and how much you will eliminate within the next month so that we can re-evaluate your use at your check-up. I understand the challenge your job poses in eliminating all alcohol from your life. Reducing your use will certainly help and perhaps we can talk at another time about reducing your use even more.
Practice Tips
  • Gastritis can present symptoms such as appetite loss, weight loss, nausea and vomiting, indigestion, belching, and a feeling of fullness after eating (MayoClinic 2007).
  • When presented with a patient who is resistant, it is important to weigh the issues of reluctance against the issues of potentially losing the patient when taking the next step.
  • Moderation may be a good middle ground step in achieving overall abstinence in the patient.
View ReferencesHide References
MayoClinic. Gastritis. Mayo Clinic Website. 2007. Available at: Accessed on: 2008-10-10.


Doctor: Do you find that you're not able to participate in social or family activities outside of work?
Tommy: My girlfriend takes care of the baby when I'm catching up on sleep, which I'm always doing, so we don't really have the time to spend with them like I should.
Doctor: While you may not feel the effects of alcohol on your body, the fatigue you have is a result of alcohol use. Your body is experiencing physical changes as a result of alcohol use.
Tommy: Yeah, but if I'm not getting drunk off the drinks, that's the main point.
Doctor: Your blood alcohol content still increases and long-term you could have serious problems such as high blood pressure, cirrhosis, and pancreatitis.
Tommy: But that's way down the road. I'll stop drinking so much before that happens. Besides, having a high tolerance is good.
Doctor: Having a high tolerance to alcohol is a sign that you've essentially disrupted your body's natural warning sign in terms of alcohol.
Tommy: I work at a bar. It's not like I can just not drink, you know?
Tommy has indications for abuse leading to dependence: consuming more than 14 drinks per week and more than 4 drinks on any given day in the past month, heavy alcohol use that interferes with social/familial/employment obligations or relationships, and tolerance.
Doctor: Based on what you've told me, your alcohol consumption qualifies as alcohol abuse. I understand your work environment may make it hard to abstain from alcohol, but it's important to pay attention to how your alcohol use is affecting you and your family.
Tommy: You think my drinking is causing the stomach problems?
Doctor: It is possible. We should run some tests in order to determine what's actually going on.


Doctor: Can you describe your symptoms in more detail?
Tommy: The pain flares up sporadically. It's definitely worse when I'm trying to sleep, but when I'm doing shots for the bar it almost kills me.
Doctor: Can you clarify what you mean by "doing shots for the bar?"
Tommy: When we serve, every night we do a little routine where one of the bartenders takes shots from the top shelf. It's a publicity thing, gets the customers to drink more of the high quality stuff.
Doctor: How often do you do this?
Tommy: We take turns, two of us at once. Mine's usually on Tuesdays, but sometimes I double up in a week.
Doctor: How many drinks do you consume at one time during these events?
Tommy: Half the shelf, so about four or five shots.
Doctor: How much do you drink during the rest of the week?
Tommy: A drink or two each night.
Doctor: What do you think of the amount of alcohol you drink?
Tommy: I have a high tolerance to alcohol. It doesn't affect me.
Doctor: The amount of alcohol you drink is actually high and is potentially harmful.
Tommy: I really don't think it's doing anything to me. Like I said, I don't feel it!
Meet Tommy


Tommy is a 34-year-old bartender who has worked in the industry for about ten years now, five at the same establishment. He enjoys his job and is very well-liked by the patrons. Tommy is very out-going and has a very welcoming personality. He lives with one of the waitresses from the bar and they have a two-year-old daughter together.

Reason for Visit

Tommy has come in because he's been experiencing stomach cramps. He has taken antacids, which seemed to help for a while, but now they're not alleviating the pain. His past medical history is unremarkable.

Normal Tolerance Levels

The table below illustrates normal tolerance levels and the body's reaction to specific amounts of alcohol. At each level of increasing blood alcohol content (BAC), the body and mind become more impaired. At the highest levels, alcohol can impair the body to such a level that death may occur.

Tolerance in a Patient With an Alcohol Use Disorder

It is important to note, however, that patients with alcohol use problems will not exhibit these tolerance thresholds. In fact, their tolerance for alcohol may be quite a bit higher. A patient with an alcohol use disorder may in fact be able to function normally with BAC levels far exceeding those that would impair an individual who does not exhibit problems with alcohol use (University of Virgina 2008).


Emotional/Personality Changes Physical/Mental Impairments

0.01 to 0.06 Decreased alertness, relaxed, sense of well-being, lowered inhibitions, joyful Coordination, judgment, concentration, thought processes
0.06 to 0.10 Disinhibition, extroversion, blunted feelings, impaired sexual pleasure Reflexes, depth perception, peripheral vision, reasoning, distance acuity, glare recovery
0.11 to 0.20 Mood swings, over-expression, overly sad or angry, boisterous Slurred speech, gross motor control, staggering, reaction time
0.21 to 0.29 Loss of understanding, blunted sensations, stupor Blackouts, unconsciousness, motor coordination
0.30 to 0.39 Unconsciousness, deep depression, death possible Heart rate, bladder function, breathing
Equal or Greater than 0.40 Unconsciousness, death Heart rate, breathing

Adapted from Virginia Tech's Student Affairs Department for Alcohol Abuse Prevention (2008)

View ReferencesHide References

The DSM-5 lists several criteria for both alcohol dependence and abuse under alcohol use disorder (APA, 2013); these were separate diagnoses in the older version of this document, the DSM-IV (APA, 2000). Patients may also be at-risk, so be aware of that potential when screening. At-risk persons do not meet the criteria for abuse or dependence yet, but have the potential to progress to these serious conditions.

If you suspect a patient may have an alcohol use disorder, a referral to an addiction specialist can help make the correct diagnosis. Abuse follows task-oriented failures, while dependence can describe physiologic dependence on alcohol.


  • Fail to fulfill role obligations
  • Recurrent use in physically hazardous situations
  • Recurrent substance-related legal problems
  • Continued use despite persistent/recurrent social/interpersonal problems
  • Tolerance
  • Withdrawal
  • Taking in larger amounts over a longer period than intended
  • Desire/experience unsuccessful attempts to quit
  • A lot of time spent obtaining, using, or recovering from the substance
  • Give up social/occupational/recreational activities
  • Continue use despite problems
View ReferencesHide References
American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 4th ed, Text Revision. Washington, DC. American Psychiatric Association. 2000.

There are a number of warning signs that are indicators of possible alcohol use problems. Red flags and warning signs sometimes overlap, so there is not a clear separation between the two and they are often present collectively.

Blackouts Blackouts are amnesic episodes that occur while a patient is intoxicated during which there is little or no recollection of events after the drinking episode (Merriam-Webster 2007 via MedlinePlus).
Liver Dysfunction/Disease
Evidence of liver dysfunction could be indicative of a problem. Elevated gamma-glutamyl transferase (GGT), aspartate aminotransferase (AST), and alanine aminotransferase (ALT) values can be indicative of long-term heavy drinking (NIAAA 2002a).
Heavy Cigarette Smoking
Heavy smoking is highly associated with dependency; it is estimated that 58% of dependent drinkers are heavy smokers (SAMHSA 2009).
Headaches Complaints of frequent headaches or other symptoms related to chronic states of tension can be signs of a problem (Burge and Schneider 1999).

Family History of Alcoholism

There is considerable evidence that a propensity toward alcoholism can be transmitted genetically in both males and females (Hawkins 2003). Additionally, the exposure of children to substance-abusing behavior during development, the presence of significant family conflict or abuse due to alcoholism or substance abuse, and permissive parental attitudes each may increase the risk of an individual becoming alcohol dependent.
Other Drug Abuse

Of the 17 million heavy drinkers over 12 years of age identified by the National Household Survey (SAMHSA 2009), 29% were using illicit drugs.
Warning Signs and Symptoms Video

(eHowhealth, 2009)
Problems viewing videos? Click on View References below to access the video link to YouTube.

View ReferencesHide References
Burge SK, Schneider FD. Alcohol-related problems: recognition and intervention. American Family Physician. 1999. Available at: Accessed on: 2008-10-10.
eHowhealth. Alcohol & substance abuse: warning signs of an alcoholic . YouTube. 2009. Available at: Accessed on: 2015-04-27.
Hawkins JD. Adolescent risk and protective factors. In: Graham AW, Schultz TK, Mayo-Smith MF, Ries RK, Wilford BB, eds. Principles of Addiction Medicine, Third Edition. Chevy Chase, Md: American Society of Addiction Medicine. 2003.
Merriam-Webster. Merriam-Webster Medical Dictionary. Merriam-Webster, Incorporated. 2006-2007. Available at: Accessed on: 2010-10-28.
National Institute on Alcohol Abuse and Alcoholism (NIAAA). Alcohol Alert No. 56: Screening for Alcohol Use Problems -- An Update. NIAAA Website. 2002a. Available at: Accessed on: 2010-10-28.
Substance Abuse and Mental Health Services Administration (SAMHSA). Results from the 2008 National Survey on Drug Use and Health: National Findings. Office of Applied Studies, NSDUH Series H-36, DHHS Publication SMA 09-4434 . 2009. Available at: Accessed on: 2010-10-29.

There is no perfect screening instrument for detecting alcohol use problems. Thus, it is important for you to keep in mind the following red flags and risk factors when seeing patients, adjusting interview questions appropriately.

Work and Family Problems Work and school problems, especially frequent absences, can be indicators of an alcohol use problem. In addition, legal and family difficulties, such as traffic violations, DUIs, restraining orders, and marital conflict, also can be indicative of an alcohol problem (Conigliaro et al. 2003).
The incidence of depression is higher in individuals with alcohol use problems (Kessler et al. 1997). In addition to screening for those that have possible comorbidities, the USPSTF has indicated that all adults should be screened for depression. This recommendation has been expanded from past suggestions to now include pregnant and postpartum women, as well as those who do not indicate prior evidence of depression (USPSTF 2016).
Blood pressure is elevated during alcohol use. Abuse of alcohol has been linked to systemic hypertension, which can be further exacerbated by withdrawal (Friedman 2003).
Sexual Dysfunction Long-term heavy drinking often is associated with reproductive dysfunction in both males and females. One mechanism may be disruptions of normal hormonal balances due to alcohol (Emanuele and Emanuele 1997).

Frequent Trauma/Accidents

This can include frequent falls due to intoxication, chronic fatigue, or amnesic episodes. (Patients' spouses and children also may experience trauma, due to domestic violence.) Three or more broken bones within a 3- to 5-year period could indicate frequent intoxication (Cummings and Cummings 2000).

Anxiety is another common comorbid psychiatric condition with alcohol (Kessler et al. 1997). One study (Nitenson and Gastfriend 2003) found anxiety disorders, including substance-induced anxiety disorders, in 11.8% of alcohol-dependent individuals but in only 3.7% of non-dependent individuals.
Gastrointestinal Problems A variety of complaints can be associated with excessive alcohol use, including abdominal pain, gastritis, diarrhea, severe vomiting, and peptic ulcer disease (Saitz 2003, Harwood et al. 1998).
Sleep Disorders Alcohol use may increase the incidence of obstructive sleep apnea. Alcohol-dependent individuals are more prone to sleep disorders than non-alcoholics. Patients in withdrawal may experience severe, extended insomnia and/or nightmares, while patients in recovery may experience continued sleep disturbance for months or years (Auerbach 2003).
Past Alcohol Use/Abuse Relapse is common in patients with a past alcohol use disorder (NIAAA 2007). Health professionals should follow-up with patients who present with past alcohol use to ensure that patients stay in remission, or help patients who have relapsed (Willenbring 2010).
View ReferencesHide References
Auerbach S. Sleep Disorders Related to Alcohol and Other Drug Use. In: Graham AW, Schultz TK, eds. Principles of Addiction Medicine, Third Edition. Chevy Chase, MD. American Society of Addiction Medicine, Inc. 2003.
Conigliaro J, Reyes CD, Parran TV, Schulz JE. Principles of screening and early intervention. In: Graham AW, Schultz TK, Mayo-Smith MF, Ries RK, Wilford BB, eds. Principles of Addiction Medicine, Third Edition. Chevy Chase, Md: American Society of Addiction Medicine. 2003.
Cummings NA, Cummings JL. The First Session With Substance Abusers: A Step by Step Guide. California, Calif: Jossey-Bass Inc. 2000.
Emanuele N, Emanuele MA. The endocrine system: alcohol alters critical hormone balance. Alcohol Research and Health. 1997; 21(1): 53-64. Available at: Accessed on: 2010-08-18.
Friedman HS. Cardiovascular Complications of Alcohol and Other Drug Use. Graham AW, Schultz TK, eds. Principles of Addiction Medicine, Third Edition. Chevy Chase, Md. American Society of Addiction Medicine, Inc. 2003.
Harwood HJ, Fountain D, Livermore G. Economic costs of alcohol abuse and alcoholism. Recent Developments in Alcohol. 1998; 14: 307-330.
Kessler RC, Crum RM, Warner LA, Nelson CB, Schulenberg J, Anthony JC. Lifetime co-occurrence of DSM-III-R alcohol abuse and dependence with other psychiatric disorders in the National Comorbidity Survey. Archives of General Psychiatry. 1997; 54(4): 313-321.
National Institute on Alcohol Abuse and Alcoholism (NIAAA). Helping Patients Who Drink Too Much: A Clinician's Guide, Updated 2005 Edition. Bethesda, MD. 2007. Available at: Accessed on: 2010-10-28.
Nitenson N, Gastfriend DR. Co-occurring addictive and affective disorders. In: Graham, AW, Schultz TK, ed. Principles of Addiction Medicine, 3rd ed. Chevy Chase, Md: American Society of Addiction Medicine, Inc. 2003.
Saitz R. Medical and Surgical Complications of Addiction. In: Graham AW, Schultz TK, eds. Principles of Addiction Medicine, Third Edition. Chevy Chase, Md: American Society of Addiction Medicine, Inc. 2003.
U.S. Preventative Services Task Force. Final Recommendation Statement - Depression in Adults: Screening. U.S. Preventative Services Task Force Website. 2016. Available at: Accessed on: 2016-02-02.
Willenbring ML. The past and future of research on treatment of alcohol dependence. Alcohol Research and Health. 2010; 33(1-2): 55-63. Available at: Accessed on: 2010-10-29.


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