The norepinephrine triangle: narcolepsy, POTS, and ME/CFS
Norepinephrine sits at the centre of several conditions that ME/CFS is often compared with. Mapping them reveals both real connections and traps.
Narcolepsy — an arousal problem with a different cause. Narcolepsy is caused by loss of hypocretin (orexin)-producing neurons. Orexin and the locus-coeruleus norepinephrine system are both waking systems, so it is tempting to lump them. The details resist that: a direct study found orexin had minimal effect on excitatory inputs to the locus coeruleus (Barcomb et al. (2022)), while hypocretin acting within the locus coeruleus mediated stress-related sleep disruption (Lo et al. (2022)). So the coupling is state- and stress-dependent, not a simple “orexin drives norepinephrine.” Whether ME/CFS arousal symptoms are primarily a norepinephrine problem, an orexin problem, or both is unresolved — and it decides which drugs make sense.
POTS — a treatment fork. In orthostatic intolerance, the response to a norepinephrine drug can reveal where the lesion is. Peripheral sympathetic denervation is reported to respond to norepinephrine precursors (droxidopa) or α1-agonists (midodrine); central autonomic failure to norepinephrine reuptake inhibitors (atomoxetine, off-label here) (Park et al. (2020); Palma and Kaufmann (2020)). These are orthostatic-hypotension data, not a ME/CFS recommendation; if the fork transfers, drug response could become a subtype test.
Why the triangle matters. These overlaps are not a slogan that “it’s all the same disease.” They are specific, testable differences — and getting them right is how a vague “norepinephrine” story becomes a set of tests a clinician can run. As throughout this series, the underlying deficit is a single unreplicated finding (Aregawi et al. (2026)).