The Medical Term is Insomnia Disorder
The term for difficulty falling asleep and staying asleep is "insomnia disorder" (or simply "insomnia"), which specifically refers to difficulty with sleep initiation, difficulty maintaining sleep, or early-morning awakening with inability to return to sleep. 1
Formal Definition
According to the American Psychiatric Association's DSM-5, insomnia disorder is defined as:
- Predominant symptoms: Difficulty with sleep initiation, difficulty maintaining sleep, or early-morning waking with inability to return to sleep
- Frequency: Occurring at least 3 nights per week
- Duration: For 3 months or more
- Consequences: Causing clinically significant distress or impairment in daytime activities
- Context: Despite adequate opportunity for sleep 1
Key Terminology Distinctions
Older terminology that you may encounter includes "chronic insomnia," which was previously used but has been replaced by the more precise term "insomnia disorder" in current diagnostic criteria 1. The diagnostic criteria are empirically similar between these terms.
Clinical Presentation Patterns
The specific sleep difficulties vary by population:
- Younger adults: More commonly report difficulty initiating sleep (sleep-onset insomnia)
- Older adults: Typically report difficulty maintaining sleep (sleep maintenance insomnia) 1
- Mixed presentation: A substantial proportion of patients experience difficulties with both sleep onset and sleep maintenance 2
Important Diagnostic Caveats
The diagnosis requires that symptoms cannot be better explained by:
- Medical or mental conditions
- Another sleep disorder (such as sleep apnea)
- Medication or substance use 1
This distinction is critical because treating secondary causes is the first priority before diagnosing primary insomnia disorder.