Insomnia or excessive sleeping, aches, pains, or digestive problems that are resistant to treatment; and fatigue, worry, or irritability may also be present.
Although clinical trials only revealed an increased risk of insomnia, post-marketing surveillance showed that the drugs are associated with a possible increase in suicidal behavior and other side effects such as agitation, aggression, anxiousness, dream abnormalities and hallucinations, depression, irritability, restlessness, and tremor.