Insomnia by Sleep Division
Insomnia is the inability to fall asleep, the inability to maintain sleep or obtain restorative sleep, despite adequate opportunity for sleep with some resulting daytime consequence, such as excessive daytime sleepiness. Insomnia can be primary or secondary. Secondary insomnia means that it is caused by some medical issue such as OSA, medication side effect (for example, Sudafed), or metabolic disorder (for example, overactive thyroid gland). The treatment of secondary insomnia is to identify and treat the underlying issue contributing to the insomnia.