Most anti depressants have a delayed onset of action and are usually taken over the course of weeks, months or years.

They are generally considered distinct from stimulants, and drugs used for an immediate euphoric effect only are not generally considered antidepressants.

Despite the name, antidepressants are often used in the treatment of other conditions, including anxiety disorders, bipolar disorder, obsessive compulsive disorder, eating disorders and chronic pain. Some have also become known as lifestyle drugs or "mood brighteners".

Other medications not known as antidepressants, including antipsychotics in low doses and benzodiazepines, are also widely used to manage depression.