Signs and symptoms
A manic episode is defined in the American Psychiatric Associations diagnostic manual as a "distinct period of abnormally and persistently elevated, expansive, or irritable mood and abnormally and persistently increased activity or energy, lasting at least 1 week and present most of the day, nearly every day (or any duration, if hospitalization is necessary)," where the mood is not caused by drugs/medication or a non-mental medical illness (e.g., hyperthyroidism), and: (a) is causing obvious difficulties at work or in social relationships and activities, or (b) requires admission to hospital to protect the person or others, or (c) the person has psychosis.To be classified as a manic episode, while the disturbed mood and an increase in goal-directed activity or energy is present, at least three (or four, if only irritability is present) of the following must have been consistently present:

Inflated self-esteem or grandiosity. Decreased need for sleep (e.g., feels rested after 3 hours of sleep). More talkative than usual, or acts pressured to keep talking. Flights of ideas or subjective experience that thoughts are racing. Increase in goal-directed activity, or psychomotor acceleration. Distractibility (too easily drawn to unimportant or irrelevant external stimuli). Excessive involvement in activities with a high likelihood of painful consequences. (e.g., extravagant shopping, improbable commercial schemes, hypersexuality).Though the activities one participates in while in a manic state are not always negative, those with the potential to have negative outcomes are far more likely.
In stages II and III mania, however, the patient may be extraordinarily irritable, psychotic or even delirious. These latter two stages are referred to as acute and delirious (or Bells), respectively. Causes
Various triggers have been associated with switching from euthymic or depressed states into mania. One common trigger of mania is antidepressant therapy. Studies show that the risk of switching while on an antidepressant is between 6-69 percent. Dopaminergic drugs such as reuptake inhibitors and dopamine agonists may also increase risk of switch. Other medication possibly include glutaminergic agents and drugs that alter the HPA axis. Lifestyle triggers include irregular sleep-wake schedules and sleep deprivation, as well as extremely emotional or stressful stimuli.Various genes that have been implicated in genetic studies of bipolar have been manipulated in preclinical animal models to produce syndromes reflecting different aspects of mania. CLOCK and DBP polymorphisms have been linked to bipolar in population studies, and behavioral changes induced by knockout are reversed by lithium treatment. Metabotropic glutamate receptor 6 has been genetically linked to bipolar, and found to be under-expressed in the cortex. Pituitary adenylate cyclase-activating peptide has been associated with bipolar in gene linkage studies, and knockout in mice produces mania like-behavior. Targets of various treatments such as GSK-3, and ERK1 have also demonstrated mania like behavior in preclinical models.Mania may be associated with strokes, especially cerebral lesions in the right hemisphere.Deep brain stimulation of the subthalamic nucleus in Parkinsons disease has been associated with mania, especially with electrodes placed in the ventromedial STN.