Critical Seriousness - Abnormal Liver Function Tests - Abnormal Hepatic Function Tests is a Life Threatening Side Effect of Tysabri Critical Seriousness - Allergic Reaction caused by a Drug - Hypersensitivity Drug Reactions is a Life Threatening Side Effect of Tysabri Critical Seriousness - Appendicitis is a Life Threatening Side Effect of Tysabri Critical Seriousness - Chest Tightness is a Life Threatening Side Effect of Tysabri Critical Seriousness - Depression is a Life Threatening Side Effect of Tysabri Critical Seriousness - Disease in the White Matter Area of the Brain - Leukoencephalopathy is a Life Threatening Side Effect of Tysabri Critical Seriousness - Fluid Retention in the Legs, Feet, Arms or Hands - Peripheral Edema is a Life Threatening Side Effect of Tysabri Critical Seriousness - Gallstones - Biliary Calculus is a Life Threatening Side Effect of Tysabri Critical Seriousness - Having Thoughts of Suicide - Suicidal Ideation is a Life Threatening Side Effect of Tysabri Critical Seriousness - Hepatitis caused by Drugs - Drug-Induced Hepatitis is a Life Threatening Side Effect of Tysabri Critical Seriousness - High Amount of Bilirubin in the Blood - Hyperbilirubinemia is a Life Threatening Side Effect of Tysabri Critical Seriousness - High Blood Pressure - Hypertension is a Life Threatening Side Effect of Tysabri Critical Seriousness - Hives - Urticaria is a Life Threatening Side Effect of Tysabri Critical Seriousness - Increased Risk of Bleeding is a Life Threatening Side Effect of Tysabri Critical Seriousness - Inflammation of Skin caused by an Allergy - Allergic Dermatitis is a Life Threatening Side Effect of Tysabri Critical Seriousness - Inflammation of the Tonsils - Tonsillitis is a Life Threatening Side Effect of Tysabri Critical Seriousness - Ovarian Cyst is a Life Threatening Side Effect of Tysabri Critical Seriousness - Progressive Disease in the White Matter of the Brain - Progressive Multifocal Leukoencephalopathy is a Life Threatening Side Effect of Tysabri Critical Seriousness - Rash - Skin Rash is a Life Threatening Side Effect of Tysabri Critical Seriousness - Reaction due to an Allergy - Allergic Reactions is a Life Threatening Side Effect of Tysabri Critical Seriousness - The Flu - Influenza is a Life Threatening Side Effect of Tysabri Critical Seriousness - Trouble Breathing - Dyspnea is a Life Threatening Side Effect of Tysabri Critical Seriousness - Urinary Tract Infection - Urinary Tract Infections is a Life Threatening Side Effect of Tysabri |