Also known as social phobia, social anxiety disorder (SAD) is treated first-line with psychotherapy. Cognitive behavioral therapy (CBT) is a type of psychotherapy that is effective for social anxiety. The premise of CBT is that events do not cause the anxiety directly. Rather, it is the maladaptive thoughts and opinions we give to events that cause us to feel anxiety. CBT works by changing the maladaptive thoughts with more adaptive ones. In addition, there is a behavioral component to CBT, where the focus is on addressing the avoidant behaviors which serve to propagate and maintain anxiety, rather than extinguish it. When you avoid your fears, you do not get to find out that the anxiety will go away on its own when you are exposed to your fears.
In addition to CBT, you also need relaxation techniques and exposure therapy to complete the treatment for social anxiety. Relaxation is needed to decrease the overall anxiety levels, so that the work with exposure and CBT can continue. Exposure therapy involves systematic desensitization, where less threatening representations of the feared stimulus are shown. When you are able to be exposed to this less threatening stimulus without anxiety, then you can move on to more threatening stimuli, until finally you are able to handle being exposed to your feared stimulus.
If for some reason you do not respond to CBT, or if you have severe social anxiety, then you may be a candidate for prescription medication for anxiety. SSRIs (selective serotonin reuptake inhibitors), SNRIs (serotonin norepinephrine reuptake inhibitors), benzodiazepines, and beta blockers are medications that are prescribed for SAD. SSRIs and SNRIs are effective for SAD, and sometimes combined with a benzodiazepine during the first few weeks of treatment, as the antidepressants tend to be activating and anxiety-provoking at the start of treatment. Once the SSRI or SNRI becomes effective weeks later, then the benzodiazepine can be tapered and discontinued. Beta blockers such as propanolol can be used on a situational basis for performance anxiety (i.e. stage fright), a type of social phobia. If propanolol is taken right before the performance, then it can help to decrease the anxiety symptoms that arise when performing in front of an audience.
Finally, there is promising research that CBT-based self-help courses and natural supplements (herbal and nutritional supplements) are viable alternatives for the treatment of anxiety disorders, such as SAD.