Anxiety disorders reflect disorders that share a general feature of excessive fear (i.e. emotional response to perceived or real threat) and/or anxiety (i.e. anticipation of future threat) and demonstrate behavioral and functional disturbances as a result. Panic attacks are a feature that can occur in the context of many anxiety disorders and reflect a type of fear response.
There has been recent interest in using psychoactive substances in conjunction with psychotherapy; the two that have received increased attention have been cannabis (marijuana) and methylenedioxymethamfetamine (MDMA, known as ecstasy or molly). These drugs are somewhat controversial, given that they also have psychoactive, i.e. "feeling high" effects. However, with increasing legalization of marijuana it is important to address whether these substances could be used to alleviate clinical symptoms of anxiety. While there have been only a few randomized clinical trials for these drugs, certain forms of cannabis have demonstrated positive effects on anxiety. Specifically, cannabidiol, a component of cannabis has been effective for Social Anxiety Disoder, and tetrahydrocannabinol (THC) has helped PTSD patients. However, the plant form of cannabis has not shown great efficacy and has potential to worsen symptoms, so should be used with caution and only under supervision of a provider. MDMA has shown some positive effects for PTSD, but should only be used as an adjunct to psychotherapy, again under clinical care.
Hyperventilation syndrome may occur when a person breathes from the chest, which can lead to overbreathing (exhaling excessive carbon dioxide in relation to the amount of oxygen in one's bloodstream). Hyperventilation syndrome can cause respiratory alkalosis and hypocapnia. This syndrome often involves prominent mouth breathing as well. This causes a cluster of symptoms, including rapid heart beat, dizziness, and lightheadedness, which can trigger panic attacks.
Social anxiety disorder (previously called social phobia): People with social anxiety disorder have a general intense fear of, or anxiety toward, social or performance situations. They worry that actions or behaviors associated with their anxiety will be negatively evaluated by others, leading them to feel embarrassed. This worry often causes people with social anxiety to avoid social situations. Social anxiety disorder can manifest in a range of situations, such as within the workplace or the school environment.