Classification & Assessment in Psychiatry · Paper A
Social anxiety disorder
Social anxiety disorder matters because the fear is specifically about being scrutinised and judged by others, not general nervousness about people. It is diagnosed as marked, persistent fear of one or more social or performance situations, such as public speaking or eating in front of others, where the person fears acting in a way that will be humiliating or embarrassing. For example, imagine a student who feels intense dread before every seminar presentation, though he feels entirely at ease chatting with the same classmates one-to-one. In practice, that fear being tied specifically to being watched and evaluated, not to people generally, is the clue to the diagnosis.
The person recognises the fear as excessive or unreasonable, but the feared situation is either endured with intense anxiety or avoided altogether, and the symptoms cause significant distress or functional impairment. Physical symptoms during exposure can include blushing, trembling, sweating and a fear of vomiting or losing control, alongside the psychological fear of humiliation. A generalised subtype exists, where fear extends across most social situations, distinct from a circumscribed fear limited to a single situation, such as public speaking alone. Take a patient who dreads any situation involving unfamiliar people, not just formal performance: that broader pattern points to the generalised subtype. In practice, identifying whether the fear is generalised or situation-specific shapes the treatment approach.
Everyone feels a flutter of nerves before being watched — a work presentation, a first date. Social anxiety disorder exists as a separate diagnosis because, for some people, that ordinary flutter becomes a fear so intense and so persistent that it stops them doing things: skipping the presentation entirely, eating alone rather than in front of colleagues, avoiding the phone call. What marks it out isn't the presence of nerves — everyone has those — it's the fear being specifically about being watched and judged, and it being severe enough to genuinely get in the way of life.
Social anxiety disorder is a marked, persistent fear of one or more social or performance situations — public speaking, eating in front of others, using a public toilet, making small talk — driven by a fear of acting in a way that will be humiliating or embarrassing. The person usually knows the fear is excessive ( is intact), but the situation still gets endured with intense dread or avoided altogether, and that avoidance or distress is significant enough to interfere with work, relationships or daily life.
The one thing most people get wrong: they assume the diagnosis is about being uncomfortable "around people" in general. It isn't. A person can be completely relaxed chatting to the same colleagues one-to-one, over coffee, with zero anxiety, and still meet full criteria for social anxiety disorder — because the trigger isn't people, it's being evaluated. The moment a situation stops being "just talking" and becomes "being watched or judged," the fear switches on. That is the diagnostic clue examiners lean on again and again.
Think of it as a threat-detection system doing its job on the wrong target. Everyone's brain has a built-in alarm for social threat — historically useful, since being rejected by your group mattered for survival. In social anxiety disorder, that alarm is calibrated too sensitively to one specific cue: signs that you're being scrutinised. A raised eyebrow, silence after you speak, someone glancing at their phone while you're mid-sentence — ordinary, mostly meaningless social noise — gets read as evidence of the exact catastrophe being feared (humiliation, rejection). The physical symptoms that follow (blushing, trembling, sweating, a racing heart) are just the body's normal threat response firing for a threat that, this time, isn't actually dangerous.
Picture two patients. The first dreads only the fifteen minutes before he presents at the Monday team meeting — heart racing, palms sweating — but is entirely at ease running the rest of that same meeting from his seat, or getting a coffee with any of the same colleagues afterwards. His fear is confined to one performance situation: this is the circumscribed, performance-only pattern. The second patient feels that same racing heart walking into the meeting at all, ordering lunch in the staff canteen, and answering an unexpected phone call from a colleague — nearly every situation where she might be observed and judged carries the same dread. Her fear has spread across most social situations: this is the generalised subtype. The distinction isn't cosmetic — it's what decides the treatment plan, covered under Management below.
Avoidant personality disorder looks similar but is broader and older: a pervasive pattern across most relationships and most of adult life, not confined to situations involving evaluation — someone with avoidant personality disorder often avoids even low-stakes new relationships generally, not just being watched. Shyness is common and usually mild; it doesn't cause the marked distress or functional impairment social anxiety disorder does. Agoraphobia's fear centres on being trapped somewhere escape or help would be hard to reach (a crowded train, a lift), not on being judged. Specific phobia targets one discrete object or situation (heights, needles, dogs) with no social-evaluation element at all.
There's no blood test or scan — diagnosis rests on a careful history establishing three things together: the fear is specifically tied to social or performance situations involving possible scrutiny; it's persistent (typically present for six months or more); and it causes real distress or gets in the way of work, education or relationships, either through avoidance or through enduring the situation with significant anxiety. Establishing the subtype matters clinically: ask whether the fear is confined to a small, specific list of performance situations, or has spread across most social contact generally.
For the generalised subtype, first-line treatment is a course of an (sertraline is well studied), and the evidence favours combining medication with cognitive behavioural therapy () over either alone — one head-to-head trial found combined CBT plus sertraline produced an 80.7% response rate after twelve weeks, ahead of either treatment by itself. CBT works by directly tackling the misfiring appraisal described above: helping the person test whether ordinary social cues really do predict humiliation. For the performance-only subtype, where the fear is confined to specific, predictable events, an as-needed beta-blocker such as propranolol (commonly 40mg, up to three or four times daily around the triggering event) can control the physical symptoms — the racing heart, the tremor — without committing to daily medication; it does nothing for generalised fear because it treats the body's physical alarm response, not the underlying appraisal. This staged approach is set out in NICE's guidance on the condition (NICE CG159, "Social anxiety disorder: recognition, assessment and treatment").
Watch for a vignette that describes someone entirely comfortable with the same people one-to-one but dreading a specific performance situation — that's the signature of the circumscribed subtype, and the "trick" answer to resist is generalised anxiety disorder or a personality disorder, both of which the situational rules out.
Social anxiety disorder is a threat-detection system correctly built but miscalibrated to one specific cue — being watched and judged — and the fix depends on whether that cue shows up in one predictable situation or almost everywhere.