Social anxiety disorder (previously known as 'social phobia') is one of the most common of the anxiety disorders. Estimates of lifetime prevalence vary but according to a US study, 12% of adults in the US will have social anxiety disorder at some point in their lives, compared with estimates of around 6% for generalised anxiety disorder (GAD), 5% for panic disorder, 7% for post-traumatic stress disorder (PTSD) and 2% for obsessive–compulsive disorder. There is a significant degree of comorbidity between social anxiety disorder and other mental health problems, most notably depression (19%), substance-use disorder (17%), GAD (5%), panic disorder (6%), and PTSD (3%).

Social anxiety disorder is persistent fear of or anxiety about one or more social or performance situations that is out of proportion to the actual threat posed by the situation. Typical situations that might be anxiety-provoking include meeting people, including strangers, talking in meetings or in groups, starting conversations, talking to authority figures, working, eating or drinking while being observed, going to school, going shopping, being seen in public, using public toilets and public performances such as public speaking. Although worries about some of these situations are common in the general population, people with social anxiety disorder worry excessively about them at the time and before and afterwards. They fear that they will do or say something that they think will be humiliating or embarrassing (such as blushing, sweating, appearing boring or stupid, shaking, appearing incompetent, looking anxious). Social anxiety disorder can have a great impact on a person's functioning, disrupting normal life, interfering with social relationships and quality of life and impairing performance at work or school. People with the disorder may misuse alcohol or drugs to try to reduce their anxiety (and alleviate depression).

Children may show their anxiety in different ways from adults: as well as shrinking from interactions, they may be more likely to cry, freeze or have tantrums. They may also be less likely to acknowledge that their fears are irrational when they are away from a social situation. Particular situations that can cause difficulty for socially anxious children and young people include participating in classroom activities, asking for help in class, joining activities with peers (such as attending parties or clubs), and being involved in school performances.

Social anxiety disorder has an early median age of onset (13 years) and is one of the most persistent anxiety disorders. Despite the extent of distress and impairment, only about half of those with the disorder ever seek treatment, and those who do generally only seek treatment after 15 to 20 years of symptoms. A significant number of people who develop social anxiety disorder in adolescence may recover before reaching adulthood. However, if the disorder has persisted into adulthood, the chance of recovery in the absence of treatment is modest when compared with many other common mental health problems.

Effective psychological and pharmacological interventions for social anxiety disorder exist but may not be accessed due to poor recognition, inadequate assessment and limited awareness or availability of treatments. Social anxiety disorder is under-recognised in primary care. When it coexists with depression the depressive episode may be recognised without detecting the underlying and more persistent social anxiety disorder. The early age of onset means that recognition in educational settings is also challenging.

Some recommendations in this guideline have been adapted from recommendations in other NICE clinical guidance. In these cases the guideline development group was careful to preserve the meaning and intent of the original recommendations. Changes to wording or structure were made to fit the recommendations into this guideline. The original sources of the adapted recommendations are shown in the recommendations.

The guideline will assume that prescribers will use a drug's summary of product characteristics to inform decisions made with individual service users.

This guideline recommends some drugs for indications for which they do not have a UK marketing authorisation at the date of publication, if there is good evidence to support that use. The prescriber should follow relevant professional guidance, taking full responsibility for the decision. The service user (or those with authority to give consent on their behalf) should provide informed consent, which should be documented. See the General Medical Council's good practice in prescribing and managing medicines and devices for further information. Where recommendations have been made for the use of drugs outside their licensed indications ('off-label use'), this is indicated.