Here are causes of narcolepsy with treatment options.
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Researchers continue to seek out the root cause of narcolepsy. The general consensus is that genetics, accompanied by an environmental trigger of some sort—a virus, for example— may affect brain chemicals and cause narcolepsy.

Scientists have discovered that people with narcolepsy are lacking in hypocretin (also called orexin), a chemical in the brain that activates arousal and regulates sleep.

Although no cure yet exists for narcolepsy, a combination of treatments can control narcolepsy symptoms. The recommended treatment for narcolepsy includes a combination of counseling, medication, and behavioral changes.

Medication is very helpful for treating the symptoms of narcolepsy. Commonly prescribed drugs for narcolepsy are stimulants, antidepressants and sodium oxybate. All medications have side effects so talk with your doctor .
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Cause of narcolepsy: Abnormalities in the structure and function of a certain group of nerve cells called hypocretin neurons in the brains of patients with narcolepsy. The cell are found in a part of the brain called hypothalamus and they usually secrete neurotransmitter substances called hypocretins. Those people who experienced narcolepsy have been found to have a markedly decrease number of hypocretin nerve cells and have decrease level of hypcoretins in the cerebrospinal flud. Very high HLA-associated in narcolepsy led to a proposal that it is an autoimmune disease similar to other HLA-associated diseases like multiple sclerosis and ankylosing spondylitis.