Disorders · Introduction
Mal de débarquement syndrome
You step off the cruise ship and the world keeps rocking — for weeks. MdDS is a central disorder of motion adaptation with a tell-tale twist: it eases when you get back into motion.
What MdDS is
“Mal de débarquement” is French for “sickness of disembarkment.” Almost everyone feels a bit of rocking for a few hours after a boat trip — that is normal. In MdDS the rocking, swaying feeling does not switch off: it lasts for weeks or months. Oddly, it gets better when the person is moving again — driving a car, for instance — and worse when they are still.
MdDS is a central disorder of persistent oscillatory self-motion — rocking, bobbing or swaying — lasting more than 48 hours, classically triggered by passive motion such as a sea voyage. Its near-defining feature is temporary relief during re-exposure to motion.1,2 It must be separated from the brief, normal ‘sea legs’ that resolve within 48 hours.
MdDS is a clinical diagnosis of exclusion: vestibular tests and imaging are normal, and the syndrome reflects maladaptive central adaptation rather than end-organ disease.3 It is strongly female-predominant and midlife, frequently misdiagnosed, and ranges from a self-limited motion-triggered illness to a chronic, refractory spontaneous form.4
The tell-tale time course
The pattern is distinctive: symptoms begin within 48 hours of the voyage, persist beyond 48 hours, and dip whenever the patient is back in passive motion — the ‘driving relief’ sign that is the single most useful pointer.
How this chapter is organised
- Pathophysiology — maladaptive velocity-storage adaptation, the neuroplasticity model, and the female predominance.
- Clinical features — the rocking, the motion-relief paradox, triggers, subtypes and course.
- Diagnosis & criteria — the Bárány Society criteria with an interactive checker, and the differential.
- Treatment & prognosis — VOR readaptation, medication, neuromodulation, and what to expect.
Key points
- MdDS is persistent rocking/swaying (>48 h), usually after passive motion such as a cruise.
- It is paradoxically relieved by re-exposure to motion (e.g. driving) — the key clue.
- It is a central, maladaptive-adaptation disorder; vestibular tests and imaging are normal.
- Strongly female-predominant and midlife; often misdiagnosed.
- Distinguish it from normal transient ‘sea legs’ and from PPPD.