Cardiac monitoring is recommended in adults with muscular canalopathy treated for myotonia with mexiletine (Namuscla®), due to a possible pro-arrhythmic effect of the product.
- To help prescribers, a number of experts – cardiologists and neurologists from various French reference centres, and an Italian pharmacologist – have issued recommendations concerning cardiac monitoring of adults being treated, based on the summary of product characteristics (SPC), a review of the literature and their clinical experience.
- They emphasise the benefit/risk ratio in favour of mexiletine for myotonia.
- An electrocardiogram (ECG) is recommended every two years during treatment (or more frequently if deemed necessary).
- For patients with cardiac abnormalities who have no contraindications to mexiletine, an electrocardiogram and echocardiography should be performed every year.
- They have also developed a decision algorithm to guide the initiation and monitoring of treatment.
