Nov 20, 2025 · Cold sore triggers vary, but they always involve your immune system being weakened in some way. Common causes include illness, sleep deprivation and stress.

Triggers for cold sores may include stress, recent fever, illness, fatigue, hormonal changes, sunlight, exposure to wind, cold weather, and more.

Nov 19, 2021 · Stress, illness, hormones, and more can trigger outbreaks. Cold sores are painful, open blisters that develop in or around your mouth, usually on your lips.

Jul 9, 2025 · Cold sores return because HSV-1 remains dormant in the trigeminal nerve and reactivates whenever internal or external stressors lower local immunity. Understanding those …

3 days ago · Cold sores, also known as fever blisters, are a common viral infection that affects millions of people worldwide. These small, fluid-filled blisters typically appear on the lips, …

May 2, 2025 · Learn the specific cold sore causes so you can avoid infection. Or get more understanding of your condition so you can get better cold sore treatment.

Aug 11, 2025 · Cold sores are painful blisters caused by an infection with the herpes simplex virus (HSV). Learn more about the causes, risk factors, symptoms, treatment, complications, and …

Jul 29, 2025 · Cold sores are small, painful blisters that typically appear on or around the lips and mouth. These lesions result from the herpes simplex virus (HSV), a highly contagious …

Jul 30, 2024 · Cold sores may seem to occur at the worst possible time—before a wedding, holiday, trip or job interview. Cold sores are largely unpredictable in terms of when they will …

Aug 21, 2025 · Common Triggers for Cold Sores: Emotional or physical stress is one of the leading triggers. Stress can weaken your immune system, making it easier for the virus to …