Depression
Anyone who suffers from mental illness will likely also experience insomnia at some point. Depression, anxiety, bipolar disorder, and even seasonal affective disorder (SAD) can disrupt neurotransmitters in the brain that influence tiredness and sleep cycles. Some symptoms of these issues include lethargy throughout the day and restless minds in the evening.
Some medications for these mental illnesses can exacerbate lack of sleep or cause difficulties getting to sleep, making matters worse.
