Are you struggling with addiction? Have you tried to quit, but had a difficult time dealing with withdrawal symptoms? You are not alone. While many people dealing with substance abuse had the intention of quitting, they kept falling back into old patterns.

Seeking help during those difficult days and weeks of getting clean could be the difference between lasting sobriety and relapsing. Finding the appropriate treatment can help you manage withdrawal symptoms and make necessary lifestyle changes to finally live drug free.

Getting the help you need is as simple as making a phone call. Our withdrawal hotline can provide you with the knowledge and resources for overcoming this difficult time in your life.

What is Drug Addiction Withdrawal?

Withdrawal refers to a set of uncomfortable symptoms that a person experiences after they decrease or stop using a drug they have become addicted to. Withdrawals can be either physical and/or psychological in nature, and are more severe with certain substances like alcohol, opioids, and benzodiazepines.

How intense the withdrawal symptoms are and how long they last can vary depending on a variety of factors, including the type of drug, how much and how often it was used, and how long the drug use was going on. How quickly the drug use was stopped also factors into withdrawals, as well as the person’s general physical and mental health status.

Withdrawals are usually uncomfortable and unpleasant, and make it harder for a person to stop using a drug, but in some cases, withdrawals can also be dangerous. .[1] Withdrawing from alcohol (for people who are physically addicted) or benzodiazepines can be especially dangerous, and often requires tapering or being treated in outpatient or inpatient treatment centers.

Withdrawal management refers to medical and pharmacological treatment that can make withdrawals safer and more comfortable, and options exist for most drugs known to cause withdrawals.

Why Does Withdrawal Happen?

When a person suddenly stops using drugs or drinking alcohol after prolonged and heavy abuse of these substances, the removal of the drug can cause a shock to the system. The brain and body go through a process of readjusting and getting used to being without the drug. This can result in a number of psychological and physical symptoms.

To really understand why withdrawal occurs, it’s helpful to understand the principle of homeostasis. Homeostasis is the body’s ability to regulate conditions so that they remain relatively constant and stable. This is essential for the body to function efficiently. When conditions change, such as when a person abuses drugs or alcohol, the body is thrown off balance. In response to this, the body attempts to maintain homeostasis and restore balance by modifying the levels of various chemicals, neurotransmitters, hormones, and processes. [2]

Because the body keeps adjusting the set point for homeostasis, the person needs larger quantities of the drug to obtain the same effects. This is called drug tolerance. When a person suddenly stops using the drug, the homeostasis that the body has developed is suddenly thrown off and forced to make a sudden adaptation to being without the drug.

Let’s take the example of heavy drinkers. After prolonged or heavy alcohol use, the brain becomes accustomed to the continuous depressive effects of alcohol. Over time, the chemistry in the brain is adjusted to compensate for the effects of alcohol. Certain neurotransmitters in the brain are produced in larger quantities than normal. When alcohol is suddenly withdrawn, the chemistry in the brain needs to be readjusted again. During this period of change, the brain struggles to regulate vital functions like circulation and breathing. This can lead to dramatic and unpredictable changes in heart rate and blood pressure, creating a risk for serious medical complications like heart attack, stroke, and death. [3]

Difference Between Detox and Withdrawal

It’s not unusual for the terms detox and withdrawal to be used interchangeably. However, professional organizations like the World Health Organization and the American Society of Addiction Medicine say there’s a difference between detox and withdrawal. Detoxification describes the internal physiological process of organs like the liver clearing the drug from a person’s system. This process leads to several uncomfortable symptoms which we refer to as withdrawal symptom.

Detox is usually the first phase of addiction treatment. The goal is to provide safe withdrawal from drugs, prepare the person for ongoing treatment, and support the person in establishing their sobriety.  [4] During detox, withdrawal symptoms are treated or managed by health and mental health professionals who can make the person more comfortable and ensure they safely withdraw from the drug.

How soon withdrawals start after a person quits and how long they will last depends on the drug they used, the dose they used, and the duration of their use. In most cases, the most severe and uncomfortable withdrawals will pass within a few days to a week, although some symptoms (often mostly psychological) can persist for weeks or even months after the person has stopped.

Standard Care for Withdrawal Management

The standard care for a person who is withdrawing from a drug depends on the drug they were using and the symptoms they are experiencing. Most drugs are generally safe to withdraw from, and treatment is aimed mainly at reducing the intensity of the symptoms and helping the person be as comfortable as possible. Often, these are prescribed medications that can help to ease the symptoms of withdrawal and often can be taken at home.

There are mainly two kinds of substances that are highly dangerous to withdraw from alone, and these are alcohol and benzodiazepines. A person can drink alcohol for many years without becoming physically addicted to alcohol and the vast majority of people who drink do not become addicted and can safely cut back or stop on their own.

When a physical addiction to alcohol develops, people experience withdrawals when they don’t drink, even only a few hours after their last drink. Withdrawals from alcohol can include shaking or trembling, psychosis and sometimes seizures that can be life-threatening. Individuals who display these symptoms are recommended for inpatient medically-monitored detox to keep them safe during this process.

Benzodiazepines are medications commonly prescribed for anxiety or insomnia, but are commonly recreationally abused. When a person becomes addicted to benzodiazepines, they need to taper off of these medications slowly to prevent withdrawals. When they stop suddenly, they can experience anxiety, spikes in blood pressure, delirium and even fatal seizures. Because of these risks, people who are quitting these medications may also be recommended for inpatient detox.

Inpatient detox includes physicians who assess the patient at the time of admission and are available to manage any medical complications that arise during withdrawal. It also includes nurses and other healthcare providers who monitor the patient during withdrawal, dispense medications, and provide emotional support.

People who are abusing other drugs like marijuana, hallucinogens, cocaine or other stimulants may experience some physical

or psychological withdrawals that are less serious in nature. Often, people are able to withdraw at home while remaining in contact with their physician or outpatient treatment center. Some of the physical symptoms of withdrawal can be alleviated with medications. [5]

Opioids like pain killers, fentanyl and heroin cause extremely uncomfortable symptoms of withdrawal that can include diarrhea, nausea, vomiting, shaking, hot and cold chills, insomnia, and fever. These symptoms are so uncomfortable that many people trying to quit end up relapsing, which is the main risk of a person quitting cold turkey or without treatment.

Because opioid overdoses account for the vast majority of fatal overdoses, it is important to have a high success rate for people who quit. For this reason, opioid withdrawal is often treated as a more medically serious condition than it actually is. Technically, there is an extremely low risk of medical issues when a person withdraws from heroin or other opioids, even though they feel really sick.

Because of the low success rate opioid addicts have quitting on their own, they are often recommended for inpatient treatment or detox or to take a medication like suboxone or methadone. These medications are opioid-like drugs that prevent the person from experiencing withdrawals.

Drug Addiction Withdrawal Symptoms

Withdrawal symptoms vary according to the type of drug abused and the severity of the addiction. Someone who has abused a drug for a prolonged period or used large amounts of the drug or used the drug frequently is likely to suffer more severe withdrawal symptoms compared to a person with mild drug abuse. The method of drug use and the presence of underlying physical and mental health issues can also affect the severity of the withdrawal syndrome. The following paragraphs describe some of the common withdrawal symptoms associated with alcohol, prescription drugs, and illegal substances.

Alcohol Withdrawal

When alcohol is suddenly withdrawn, the chemistry in the brain needs to be readjusted again. During this period of change, the brain struggles to regulate vital functions like circulation and breathing. This can lead to dramatic and unpredictable changes in heart rate and blood pressure, creating a risk for serious medical complications like heart attack, stroke, and death.

Other symptoms of alcohol withdrawal include anxiety, sweating, tremors, dehydration, insomnia, nausea, vomiting, and diarrhea. In severe cases, the person may experience delirium, hallucinations, extreme agitation, seizures, and severe fluctuations in blood pressure and body temperature.

Opioid Withdrawal

Opioid drugs include the illegal drug heroin as well as prescription pain medications, such as codeine, OxyContin, and methadone. Opioid withdrawal can feel like a bad case of the flu and it is usually not life-threatening. Symptoms of opioid withdrawal include anxiety, insomnia, nausea, vomiting, diarrhea, sweating, hot and cold flashes, muscle cramps, and watery eyes and nose.

Benzodiazepine Withdrawal

Benzodiazepines are a class of drugs used to treat anxiety and sleep disorders. Long-term use of benzos can lead to dependence. During withdrawal from benzodiazepines like Valium and Xanax, patients may experience symptoms such as anxiety, insomnia, agitation, restlessness, irritability, inability to focus, poor memory, and muscle aches. In some cases, people withdrawing from benzodiazepines can have life threatening seizures, which often means they need to slowly taper off the medication rather than stopping quickly.

Stimulant Withdrawal

Stimulants are drugs like methamphetamine (meth) and cocaine. Although their effects are different, the withdrawal syndrome for meth and cocaine is similar. Symptoms include depression, agitation, irritability, muscle aches, increased sleeping, and increased appetite. Heavy methamphetamine use can give rise to hallucinations and paranoia during withdrawal, which may need to be managed with anti-psychotic medications.

Inhalant Withdrawal

Inhalants are volatile substances that produce chemical fumes that are inhaled for their psychoactive (mind-altering) effects. They include things like hair sprays, fabric protectors, and whipped cream dispensers. Inhalant addiction is not well understood and only some people develop a dependence on these substances or experience withdrawal symptoms. Symptoms of inhalant withdrawal may include nausea, headache, tremors, insomnia, lethargy, anxiety, poor concentration, irritability, and hallucinations.

Marijuana Withdrawal

The withdrawal syndrome associated with cannabis (marijuana) is typically mild and can include symptoms such as irritability, restlessness, anxiety, fear, dissociation, poor appetite, sleep disruption, night sweats, vivid dreams, and tremors.

Duration and Timeline of Withdrawal Symptoms

The onset, duration, and severity of withdrawal symptoms vary with different drugs and alcohol. There is no way to predict how bad withdrawal symptoms will be in any particular person. However, the typical durations and timelines associated with withdrawal from the most common drugs of abuse are listed below.

Alcohol Withdrawal Timeline and Duration

  • Symptoms appear 3-24 hours after the last drink.
  • Symptoms are severe for the first 48-72 hours and can include delirium tremens (DT’s).
  • Symptoms last for 2-10 days.

Heroin Withdrawal Timeline and Duration 

  • Symptoms appear 8-24 hours after last use.
  • Symptoms last for 4-10 days.

Methadone Withdrawal Timeline and Duration

  • Symptoms appear 12-24 hours after the last use.
  • Symptoms last for 10-20 days.

Benzodiazepine Withdrawal Timeline and Duration

  • Symptoms appear 1-2 days after the last dose for medications like alprazolam and temazepam (Xanax, Restoril) that are shorter lasting, and continue for 2 weeks to one month.
  • Symptoms appear 2-7 days after the last dose for medications like diazepam (Valium) that are long lasting, and continue for between two weeks and two months.

Stimulant Withdrawal Timeline and Duration

  • Symptoms begin within 24 hours of last use.
  • Symptoms last for 3-5 days.

Inhalant Withdrawal Timeline and Duration

  • Symptoms begin a few hours to a few days after stopping use.
  • Symptoms last from 2 days to 2 weeks.

Marijuana Withdrawal Timeline and Duration

  • Symptoms are usually mild and can last for 1-2 weeks.

Post-Acute Withdrawal Syndrome

In some instances, withdrawal symptoms can last beyond the usual timelines or reappear after first getting better. This is known as protracted or extended withdrawal or post-acute withdrawal syndrome (PAWS). PAWS symptoms can last for weeks to months after cessation of substance use. They typically consist of mood swings, anxiety, irritability, and insomnia. There can be difficulties with learning, problem-solving, and memory. Some people experience cravings, obsessive-compulsive behaviors, and difficulties with social relationships.

PAWS symptoms are most common after withdrawal from alcohol, opioids, and benzos. It is believed that roughly 90% of opioid abusers and 75% of recovering alcoholics experience protracted withdrawal symptoms. [6] These symptoms are often more psychological than physical, but can create additional barriers for people in recovery from addiction.

Symptom Management During Withdrawal

During medically-supervised drug addiction withdrawal, clinicians use a variety of medications to treat the physical symptoms of withdrawal. For example, benzodiazepines may be used during alcohol withdrawal to manage discomfort, delirium, and seizures. [7]Medicines for other symptoms, such as muscle aches, anxiety, nausea, and insomnia are offered under careful supervision. Patients may also be given vitamin supplementation and encouraged to hydrate aggressively as part of withdrawal management.

The use of medications and close clinical monitoring during drug withdrawal has several benefits, including: [8]

  • Improved patient survival
  • Increased compliance with treatment
  • Decreased drug use
  • Reduction in criminal activity among people with substance use disorders
  • Increased ability to obtain and maintain employment
  • Better outcomes in pregnant women with substance use disorders

Medication-Assisted Treatment for Drug Withdrawal

In addition to symptomatic management during drug withdrawal, the Food and Drug Administration (FDA) in the United States has approved several medications for the treatment of addiction, specifically opioid addiction and alcohol dependence.

There is a misconception among some people that medication-assisted treatment (MAT) is simply substituting one drug for another. However, this is not true. Certain medications mimic the effects of harmful drugs and are used during withdrawal to relieve physical symptoms and reduce psychological cravings. Examples of medications used during drug withdrawal include:

Naltrexone (Vivitrol) reduces the urge to drink or use opioid drugs by blocking opioid receptors in the brain, which are responsible for the pleasurable effects of these substances. When the receptors are blocked, the person stops associating opioid drugs or alcohol with pleasurable feelings. [9]

Disulfiram (Antabuse) was the first medication approved for use during alcoholism withdrawal. It works by producing unpleasant side effects such as nausea, vomiting, flushing, and fast heart rate if a person consumes alcohol. The fear of feeling sick encourages recovering alcoholics to remain abstinent. [10]

Acamprosate (Campral) decreases cravings for alcohol and reduces withdrawal-associated distress by providing relief of physical and emotional symptoms. This medication appears to work by balancing neurotransmitters in the brain. [11]

Methadone is an opioid medication that is used to treat severe opiate addiction. It works by attaching to the same opioid receptors in the brain as heroin and opioid painkillers and blocking or blunting the effects of these drugs. Methadone maintenance in recovering opioid addicts helps suppress cravings and allows for a smoother withdrawal. [12]Methadone is dispensed through federally-regulated opioid treatment programs (OTPs) under the supervision of a physician because of its potential for addiction. [13]

Buprenorphine (Subutex) has a similar mechanism of action to methadone but has a lower potential for addiction. It is available in combination with naloxone (Suboxone) for use in the treatment of opioid dependence. Buprenorphine helps reduce the extremely uncomfortable symptoms of opiate withdrawal and is an effective means to decrease opioid drug use. [14]

Risk Factors for Complicated Withdrawal

Some people are at higher risk of experiencing severe withdrawal with numerous medical complications. The risk factors for complicated withdrawal include: [15]

  • Older age (more than 65 years old).
  • Numerous previous drug withdrawal episodes during the person’s lifetime.
  • Comorbid medical or surgical conditions (for example, traumatic brain injury).
  • History of delirium or seizures during prior withdrawals.
  • Long duration or heavy use of drugs or alcohol.
  • Autonomic hyperactivity on presentation (manifested by high blood pressure, heart rhythm irregularities, high or low body temperature, and numerous other symptoms). [16]
  • Concomitant use of multiple addictive substances.
  • Co-occurring psychiatric disorders.

Patients with severe withdrawal require more intensive care and more frequent monitoring to ensure effective outcomes.

Delirium Tremens: Severe Alcohol Withdrawal

Delirium tremens (DT) is a type of severe alcohol withdrawal syndrome that can potentially result in death. Also called withdrawal delirium, it is characterized by symptoms of agitation, hallucinations, confusion, hyperactivity, and delirium (fluctuating cognition and sleep/wake cycles). Patients with DT also have alcohol withdrawal symptoms like tremors, nausea, agitation, and seizures.

Delirium tremens usually appears after long periods of heavy drinking. It affects roughly 2% of people with alcohol addiction, although some studies have reported a prevalence of up to 12%.

DT symptoms typically develop 48-72 hours after cessation of heavy drinking. The condition is relatively short-lived with a duration of 3-4 days. However, DT is a medical emergency and requires timely intervention to reduce complications and prevent death. Treatment consists mainly of supportive care with IV fluids and medications such as benzodiazepines to calm agitation and prevent hallucinations. [17]

The risk factors for delirium tremens include a prior history of DT, presence of infectious comorbidities, development of early withdrawal symptoms, and a genetic predisposition (family history of DT). [18]

Is Quitting Cold Turkey Dangerous?

Generally, quitting most drugs cold turkey is safe to do, especially after consulting with a doctor or medical professional. However, people who are physically addicted to alcohol and experience shaking hands, sweating or other physical symptoms when they need a drink should not detox on their own.

People who have been abusing benzodiazepines should also not stop using cold turkey on their own but should instead consult with their prescribing physician or another medical professional. Usually, a tapering schedule will be recommended to help ensure that withdrawal is safe and gradual in nature.

People who are trying to stop using other drugs may not have medical complications when they quit using, but most will experience some psychological issues. These can include intense drug cravings and urges that make it very difficult for a person to stop on their own. An advantage of inpatient rehab is that the person does not have access to drugs or alcohol. In contrast, withdrawal at home carries the risk of giving in to cravings and abandoning the drug withdrawal.

Experiencing other mental health symptoms like anxiety, depression, guilt, or excessive shame is also common after a person stops using drugs. Often, drugs were used as a method of coping or avoiding these emotions and without the drug, these often resurface. Because of the difficulty associated with these emotions, people who stop using should seek professional counseling and also consider a support group like Alcoholics/Narcotics Anonymous or Smart recovery. The support of family and friends is also an essential factor tied to long-term sobriety. [19]

Coping with Drug Addiction Withdrawal

Alcohol or drug withdrawal can be overwhelming and frightening to many people with a long history of substance abuse. There are various things a person can do to make the withdrawal process easier, such as:

Education: Understanding what is happening in your brain and body during the withdrawal process helps many people feel more prepared and better able to cope with their discomfort. It is reassuring to know that many of the symptoms you will experience signal the healing and recovery process happening in your body and brain. Seek out information online to educate yourself about withdrawal from the drug you’ve been abusing.

Support. Even when you’re undergoing withdrawal under the supervision of a healthcare team, it’s important to have social support. Family and friends can support recovering addicts by being there during the withdrawal process.

Nutrition. Recovering addicts should focus on eating well-balanced, nutritious, healthy meals during withdrawal. This allows the body to replace lost nutrients and aids the healing process by supplying energy.

Hydration. Some of the most common withdrawal symptoms include vomiting, diarrhea, increased sweating, and other flu-like symptoms. It’s important to stay well hydrated during the withdrawal process to help the body’s natural detoxification abilities.

Exercise: People going through drug withdrawal should try to get some physical activity every day, such as walking, swimming, yoga, or sports. Exercise boosts mood, reduces anxiety symptoms, and decreases the urge to use drugs or alcohol.

Sleep. Withdrawal from drugs and alcohol is often associated with sleeping difficulties. However, it is vital to try and get adequate rest. People going through drug withdrawal should practice good sleep hygiene and maintain a regular sleep schedule as much as their symptoms will allow.

Medications. There are various over-the-counter and prescription medications available to relieve withdrawal symptoms such as nausea, diarrhea, headache, etc. It is advisable to discuss all medications with a healthcare provider before using them during drug addiction withdrawal.

Meditation: Mindfulness and meditation has been proven to help reduce stress, promote a positive mood and restore energy levels. Because these practices train your mind to refocus attention away from upsetting thoughts, you will also become better equipped to resist cravings and urges. Setting aside just 15-30 minutes a day to practice mindfulness or meditation can be incredibly helpful in the withdrawal process.

What to Expect When Calling a Withdrawal Hotline

If you’re struggling right now, a simple call may set you at ease. A withdrawal helpline can help you:

  • Gain insights into addiction and drug withdrawal
  • Have someone talk you through a difficult moment in your life
  • Learn specific facts about the drug you are detoxing from
  • Find out more about physical and psychological withdrawal
  • Learn how to get a loved one through withdrawal
  • Discover treatment options for making withdrawal more tolerable
  • Learn how changing certain aspects of your life can help maintain your sobriety
  • Get specific resources based on your personal needs

Of course, some people hesitate to call a drug and alcohol withdrawal hotline. After all, wouldn’t it be easier to just get a little more of the drug? Tomorrow will be a different day. This mentality is not you–it’s the addiction talking to you. While you may feel uncomfortable, even sick, the help for lasting change is just a phone call away.

Tomorrow will be a better day if you bravely take the steps to do your best today.

Last updated: October 1, 2020

About the author

Hailey Shafir
Hailey Shafir, M.Ed., LCMHCS, LCAS, CCS

Hailey Shafir is a licensed addiction specialist and mental health counselor. She graduated from North Carolina State University with a master of education in clinical mental health counseling in 2012, and has developed deep expertise in the areas of mental health, behavioral addictions and substance abuse. She is passionate about using this knowledge to raise awareness, provide clear and accurate information, and to improve the quality of treatment for these disorders.

Hailey is an LCMHCS (license number: S9539) under the North Carolina Board of Mental Health Counselors, and an LCAS (ID: LCAS-21333) and CSS (ID: CCS-20721) under the North Carolina Addictions Specialist Professional Practice Board.


1 Hodding GC, Jann M, Ackerman IP. Drug withdrawal syndromes– a literature review. West J Med. 1980;133(5):383-391.
2 Gupta M, Gokarakonda SB, Attia FN. Withdrawal Syndromes. [Updated 2020 Jul 2]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2020 Jan. Available from:
3 Harvard Health Publishing. Alcohol Withdrawal. Published April, 2019. Available online: Accessed July 24, 2020.
4 Center for Substance Abuse Treatment. Detoxification From Alcohol and Other Drugs. Rockville (MD): Substance Abuse and Mental Health Services Administration (US); 1995. (Treatment Improvement Protocol (TIP) Series, No. 19.) Chapter 1—Introduction.Available from:
5 Clinical Guidelines for Withdrawal Management and Treatment of Drug Dependence in Closed Settings. Geneva: World Health Organization; 2009. 4, Withdrawal Management.Available from:
6 UCLA Semel Institute for Neuroscience and Human Behavior. Post-Acute Withdrawal Syndrome (PAWS). No date. Available online. Accessed July 24, 2020
7 World Health Organization. Management of Alcohol Withdrawal. 2012. Available online. Accessed July 24, 2020.
8 Substance Abuse and Mental Health Services Administration (SAMHSA). Medication and Counseling Treatment. No date. Available online. Accessed July 24, 2020.
9 Anton RF. Naltrexone for the management of alcohol dependence. N Engl J Med. 2008;359(7):715-721. doi:10.1056/NEJMct0801733
10 Skinner MD, Lahmek P, Pham H, Aubin HJ. Disulfiram efficacy in the treatment of alcohol dependence: a meta-analysis. PLoS One. 2014;9(2):e87366. Published 2014 Feb 10. doi:10.1371/journal.pone.0087366
11 Witkiewitz K, Saville K, Hamreus K. Acamprosate for treatment of alcohol dependence: mechanisms, efficacy, and clinical utility. Ther Clin Risk Manag. 2012;8:45-53. doi:10.2147/TCRM.S23184
12 Kleber HD. Pharmacologic treatments for opioid dependence: detoxification and maintenance options. Dialogues Clin Neurosci. 2007;9(4):455-470.
13 Substance Abuse and Mental Health Services Administration (SAMHSA). No date. Available online. Accessed July 24, 2020.
14 Welsh C, Valadez-Meltzer A. Buprenorphine: a (relatively) new treatment for opioid dependence. Psychiatry (Edgmont). 2005;2(12):29-39.
15 The ASAM Clinical Practice Guideline on Alcohol Withdrawal Management. No date. Available online. Accessed July 24, 2020
16 Oxford Medicine Online. Autonomic Hyperactivity. Edited by Eduardo Benarroch. DOI: 10.1093/med/9780199920198.001.0001 Published online May 2014.
17 Grover S, Ghosh A. Delirium Tremens: Assessment and Management. J Clin Exp Hepatol. 2018;8(4):460-470. doi:10.1016/j.jceh.2018.04.012
18 Thiercelin N, Rabiah Lechevallier Z, Rusch E, Plat A. Facteurs de risque du delirium tremens : revue de la littérature [Risk factors for delirium tremens: a literature review]. Rev Med Interne. 2012;33(1):18-22. doi:10.1016/j.revmed.2011.08.002
19 American Family Physician. Outpatient Detoxification of the Addicted or Alcoholic Patient. CHRISTOPHER D. PRATER, M.D., KARL E. MILLER, M.D., and ROBERT G. ZYLSTRA, ED.D., L.C.S.W., University of Tennessee College of Medicine, Chattanooga, Tennessee. Am Fam Physician. 1999 Sep 15;60(4):1175-1182.