Yohimbine and yohimbine-containing products — as well as supplements that have a similar mechanism, such as rauwolscine — should be avoided, because they can provoke anxiety in people with anxiety disorders.[1]
Additionally, although stimulants do not always cause anxiety symptoms, many create a stress response that could worsen existing symptoms. People with anxiety disorders might not need to stop using stimulants entirely, but they may want to avoid frequent use, especially if anxiety symptoms worsen.
Caffeine is the stimulant least likely to cause anxiety symptoms. Ideally, 100–200 mg of caffeine should be paired with an equal dose of theanine, an amino acid that can tame the anxiety caused by caffeine in some people without impairing caffeine’s stimulatory effect. In fact, the improvements in concentration (focus and attention span) induced by caffeine and theanine, respectively, have been shown to be synergistic (work together).