long-term alcohol use is associated with anxiety disorders,[17] with evidence that prolonged abstinence can result in a disappearance of anxiety symptoms.[18] However, it can take up to two years for anxiety symptoms to return to baseline in about a quarter of people recovering from alcoholism.[19]

In one study in 1988–90, illness in approximately half of patients attending mental health services at British hospital psychiatric clinic, for conditions including anxiety disorders such as panic disorder or social phobia, was determined to be the result of alcohol or benzodiazepine dependence. In these patients, anxiety symptoms, while worsening initially during the withdrawal phase, disappeared with abstinence from benzodiazepines or alcohol. Sometimes anxiety pre-existed alcohol or benzodiazepine dependence, but the dependence was acting to keep the anxiety disorders going and often progressively making them worse. Recovery from benzodiazepines tends to take a lot longer than recovery from alcohol, but people can regain their previous good health.[19]

Tobacco smoking has been established as a risk factor for developing anxiety disorders.[20]

Excessive caffeine usage has been linked to anxiety.[21]