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Generalized anxiety disorder (GAD) is characterized by excessive, almost daily anxiety and worry for ≥ 6 mo about many activities or events. The cause is unknown, although it commonly coexists in people who have alcohol abuse, major depression, or panic disorder. Diagnosis is based on history and physical examination. Treatment is psychotherapy, drug therapy, or both.

GAD is common, affecting about 3% of the population within a 1-yr period. Women are twice as likely to be affected as men. The disorder often begins in childhood or adolescence but may begin at any age.

Symptoms and Signs

The focus of the worry is not restricted as it is in other mental disorders (eg, to having a panic attack, being embarrassed in public, or being contaminated); the patient has multiple worries, which often shift over time. Common worries include work and family responsibilities, money, health, safety, car repairs, and chores.

The course is usually fluctuating and chronic, with worsening during stress. Most people with GAD have one or more other comorbid psychiatric disorders, including major depression, specific phobia, social phobia, and panic disorder.

Diagnosis

• Clinical criteria

Diagnosis is clinical based on criteria in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Text Revision (see Table 1: Anxiety Disorders: Diagnosis of Generalized Anxiety Disorder)

Table 1
Diagnosis of Generalized Anxiety Disorder With exclusion of other causes, affirmative answers to the following questions confirm the diagnosis: Does the patient have excessive, almost daily anxiety and worry about many activities or events? Have the anxiety and worry lasted for ≥ 6 mo? Does the patient have difficulty controlling the worry? Does the patient also have ≥ 3 of the following symptoms: Restlessness Unusual fatigability Difficulty concentrating Irritability Muscle tension Disturbed sleep Have at least some of these symptoms been present for a majority of days in the past 6 mo? Is the focus of worry broader than that in other anxiety disorders? Have symptoms caused substantial distress or interfered with functioning?

Treatment

• Antidepressants and often benzodiazepines

Certain antidepressants, including SSRIs (eg, paroxetineSome Trade Names
PAXIL
Click for Drug Monograph
, starting dose of 20 mg po once/day) and serotonin-norepinephrineSome Trade Names
LEVOPHED
Click for Drug Monograph
reuptake inhibitors (eg, venlafaxineSome Trade Names
EFFEXOR
Click for Drug Monograph
extended-release, starting dose 37.5 mg po once/day) are effective but typically only after being taken for at least a few weeks. Benzodiazepines (anxiolytics—see Table 2: Anxiety Disorders: Benzodiazepines) in small to moderate doses are also often and more rapidly effective, although sustained use usually causes physical dependence. One strategy involves starting with concomitant use of a benzodiazepine and an antidepressant. Once the antidepressant becomes effective, the benzodiazepine is tapered.

BuspironeSome Trade Names
BUSPAR
Click for Drug Monograph
is also effective; the starting dose is 5 mg po bid or tid. However, buspironeSome Trade Names
BUSPAR
Click for Drug Monograph
can take at least 2 wk before it begins to help.

Psychotherapy, usually cognitive-behavioral therapy, can be both supportive and problem-focused. Relaxation and biofeedback may be of some help, although few studies have documented their efficacy.

Table 2
Benzodiazepines Drug Starting Oral Dose Maintenance Oral Dose* Onset/ Duration AlprazolamSome Trade Names XANAX Click for Drug Monograph † 0.25 mg bid Extended-release: 0.5 mg once/day 1 mg tid Extended-release: 3 mg once/day Intermediate/intermediate ChlordiazepoxideSome Trade Names LIBRIUM Click for Drug Monograph ‡ 5 mg tid 25 mg tid Intermediate/long ClonazepamSome Trade Names KLONOPIN Click for Drug Monograph † 0.25 mg once/day 1 mg tid Intermediate/long ClorazepateSome Trade Names TRANXENE Click for Drug Monograph ‡ 7.5 mg bid 7.5 mg tid or 15 mg bid Single-dose (sustained release): 22.5 mg once/day after stabilized on 7.5 mg tid Rapid/long DiazepamSome Trade Names VALIUM Click for Drug Monograph ‡ 2 mg tid 5 mg tid Rapid/long LorazepamSome Trade Names ATIVAN Click for Drug Monograph 0.5 mg tid 1 mg tid Intermediate/short OxazepamSome Trade Names SERAX Click for Drug Monograph 10 mg tid 15 mg qid Slow/short *Maintenance dose can vary and depends on individual response. †An oral disintegrating tablet or wafer is available. Onset does not differ from other formulations. Although these tablets disintegrate in the mouth, they are absorbed in the stomach and intestine, as are standard tablets. ‡Generally, these drugs are not recommended in the elderly because of a long half-life.

Last full review/revision August 2007 by John H. Greist, MD

Content last modified August 2007