Nocturnal panic attacks wake you from sleep in a state of full physiological alarm — racing heart, breathlessness, sweating, terror. A substantial minority of people with panic disorder experience them, and for some they’re the main presentation.
The distinctive and disturbing feature is the absence of content. There’s no dream to blame and no thought that preceded it, which makes the catastrophic interpretation — that something is physically wrong with your body — far more compelling than during the day.
What they aren’t
Not nightmares. Nightmares occur in REM sleep, have content you can recall, and you wake from them oriented. Nocturnal panic typically arises from non-REM sleep, usually in the earlier part of the night, with no dream at all.
Not night terrors. In night terrors the person isn’t properly awake, is difficult to rouse, and usually has no memory of it. In nocturnal panic you’re fully awake and remember it in unpleasant detail.
Not, usually, a heart problem. Though see below, because there are things worth ruling out.
What to rule out
This is the one presentation where the medical workup deserves a bit more attention than usual.
Sleep apnoea. Waking gasping, with a racing heart, is a classic presentation, and it’s routinely misdiagnosed as anxiety. Worth asking about if you snore, wake unrefreshed, or have been told you stop breathing.
Reflux. Can produce chest discomfort and waking, particularly lying flat.
Cardiac arrhythmias. Some present at night. A one-off assessment settles it.
Thyroid, and alcohol. Alcohol in particular fragments sleep in the second half of the night and produces rebound arousal, and a great many nocturnal panic attacks follow an evening’s drinking by four hours.
The loop it creates
Nocturnal panic tends to produce fear of sleep itself, which produces sleep deprivation, which raises baseline arousal, which makes further attacks more likely. People start staying up, or sleeping with the light on, or waking their partner.
Those precautions are safety behaviours and they maintain it, in exactly the way daytime ones do.
Treatment
The same as for daytime panic, and it works.Interoceptive exposure is the core — the sensations are identical, so learning that they’re harmless transfers to the night.
Alongside it, CBT-I if fear of sleep has developed, because at that point you’ve two problems and the insomnia needs its own treatment. And attention to alcohol, which is frequently the single largest modifiable factor.
What not to do: stay up to avoid it, or check your pulse on waking. Both are the same precaution that keeps panic alive in daylight.