AFM Signs & Symptoms Most of those diagnosed with AFM report having a respiratory or gastrointestinal illness before the onset of weakness. The predominant presentation is a rapid onset of weakness within hours to a few days that may affect the limbs, face, and the muscles that control breathing and/or swallowing. The weakness may rapidly progress from limb weakness to more severe symptoms, including respiratory failure, so hospitalization for observation is recommended even with mild symptoms.
