- A 43-year-old woman was diagnosed with myasthenia gravis after a myasthenic crisis requiring intubation, intravenous immunoglobulins and corticosteroids.
- Taking pyridostigmine 60mg twice a day, she had another myasthenic attack three months later with fatigue, shortness of breath and headaches for a fortnight.
- Two weeks before each attack, the patient had dyed her hair red the first time and blue the second.
- Both dyes contained methylisothiazolinone, a preservative and powerful biocide that has been widely used in paints and skincare products since 2010 (notably to replace parabens).
In addition to the known myasthenic crisis triggers, the authors warn of the appearance over time of other deleterious molecules, including ingredients in beauty products.
