Sexual Health STDs Herpes Cold Sore Outbreak Overview Prevalence, Symptoms, Stages, Safety, and Treatment By Christina Donnelly Christina Donnelly LinkedIn Christina Donnelly is a freelance writer and editor who has extensively covered health and science content. She currently works at Anthem Health as a content lead. Learn about our editorial process Updated on December 04, 2021 Medically reviewed Verywell Health articles are reviewed by board-certified physicians and healthcare professionals. These medical reviewers confirm the content is thorough and accurate, reflecting the latest evidence-based research. Content is reviewed before publication and upon substantial updates. Learn more. by Leah Ansell, MD Medically reviewed by Leah Ansell, MD LinkedIn Leah Ansell, MD, is board-certified in cosmetic and medical dermatology. She is an assistant professor at Columbia University and works in private practice in New York City. Learn about our Medical Expert Board Print Table of Contents View All Table of Contents Causes Symptoms and Stages Safety Treatment Prevention Cold sores are caused by the herpes simplex virus type 1 (HSV-1). There is no cure for HSV-1. Once you contract the virus, it stays in your system for life. The virus causes tiny blisters to form around the mouth and nostrils. The blisters pop and merge into a cold sore. Anyone can get a cold sore. Most people contract herpes through physical contact with an infected person. You can infect others with your saliva even if you don't have a visible cold sore. This article discusses the causes, symptoms, and stages of a cold sore outbreak. It also explores how to treat a cold sore and prevent future outbreaks. Causes of Cold Sores Herpes simplex virus 1 is very contagious. You can be exposed to the virus through physical contact with an infected person. This includes: Intimate contactKissingSharing food or drinksSharing items like lip balm, razors, or towels Research suggests genetics may make some people more susceptible to cold sores. The exact mechanism, however, is still unknown. Once infected with herpes simplex, you will have the virus for the rest of your life. The virus usually stays dormant in the body. This means you won’t show any symptoms unless it is activated. A number of factors can cause the virus to be activated. These include: Stress Fatigue Hormonal changes, including menstruation Illness Dental work Exposure to extreme weather Sunlight Prevalence Research suggests that, worldwide, 67% of people ages 0 to 49 carry HSV-1. Verywell / Brianna Gilmartin Cold Sore Symptoms and Stages Some people experience a cold sore outbreak within a few days of exposure. Other people carry the virus but never have symptoms. A cold sore can last two to four weeks from early symptoms to completely healed. During that time, it goes through three distinct stages. These stages can vary between first outbreaks and recurrences. How to Tell the Difference Between a Cold Sore and Pimple Stage 1 The first stage of an outbreak lasts one to two days. During this time, tingling, itching, or even soreness around the mouth is common. If this is a recurrence, you’ll likely feel this in the same locations as previous outbreaks. Some people only experience this first stage and do not develop cold sores. Stage 2 After a few days, small, hard, fluid-filled blisters begin to form on the lips, nose, cheeks, or other parts of the face. At this stage, the blisters and fluid are very contagious. Avoid close physical contact with others. Blisters can be spread to other parts of the body. If you touch a cold sore, wash your hands immediately. This will help you avoid spreading the virus to other areas. Be especially careful to not touch your eyes after touching a cold sore. See a doctor if you have: Blisters near the eyesSensitivity to lightPain or grittiness in the eyes Children can develop cold sores inside the mouth. These are commonly mistaken for canker sores, which are small lesions in the mouth. If your child develops sores in the mouth, see a pediatrician for a diagnosis. Stage 3 In the final stage, the blisters may merge and burst. This causes small, open sores that ooze fluid. These sores are very painful and highly contagious. After a few days, the open sores begin to dry out and scab. Cold sore scabs can be very itchy and may crack. Avoid biting or picking at them. This can make the discomfort worse. The scabs will begin to fall off and heal between five and 15 days after the sores first appear. When To See a Healthcare Provider The initial HSV-1 infection is usually the worst. This is because the body hasn't yet built up defenses to the virus. If you or a loved one experience the following, see a doctor: High and persistent fever Problems swallowing Red, irritated eyes Sores near the eyes Trouble breathing Also see a doctor if the sores last more than 15 days or reoccur frequently. If you have a cold sore and a weakened immune system, call your doctor. After the first infection, the virus remains inside the nerve cells of the face. Unless the virus is triggered to reactivate, you may not have symptoms again. If you do have another outbreak, you can expect to develop a cold sore in the same place. The virus typically reactivates in the same spot each time. Symptoms, however, should be less severe in following outbreaks. Recap Cold sores often progress through three stages. In the first stage, you may have tingling and itching. In the second, blisters develop. In the third, the blisters burst and then scab over. Other Symptoms During a first outbreak, you may also have flu-like symptoms in addition to a cold sore. These include: Mild fever Headache Swollen lymph nodes, bean-shaped glands under the skin that contain immune cells Muscle aches or general body pain Sore throat Difficulty swallowing Fatigue, or lack of energy Safety During a Cold Sore Outbreak Cold sores are infectious until they scab over. If you have a cold sore, avoid: Touching themKissingIntimate contact such as oral sexSharing food, drinks, or personal itemsPhysical contact with anyone who has a weakened immune systemPhysical contact with children Cold sores can cause serious health issues in newborns, children, and people with weakened immune systems. It is important to take steps to avoid infecting others with HSV-1. Why You Should Tell Your Partner You Have Herpes Simplex Virus 1 HSV-1 Treatment of Cold Sores Cold sores cause pain, irritation, and even embarrassment. Fortunately, you can treat the pain and symptoms to feel better faster. Medications Certain prescription oral antiviral medications can shorten the duration of a cold sore. To work, these medicines need to be taken within 72 hours of an outbreak. These include: Famvir (famciclovir) Valtrex (valacyclovir) Your doctor may recommend antiviral creams. These are applied directly to the cold sore. They include: Abreva (docosanol 10% cream), available without a prescription Denavir (penciclovir 1% cream) Zovirax (acyclovir 5% cream) Always wash your hands after applying topical medicines. Over-the-counter pain relievers such as Advil (ibuprofen) or Tylenol (acetaminophen) can help relieve the pain, swelling, and irritation caused by blisters or open sores. Home Remedies and Lifestyle A cold compress can reduce pain and irritation. Use a cool, damp towel instead of an ice pack. Apply compresses a few times each day for five to 10 minutes at a time. Otherwise, keep the affected area clean and dry. Don't put makeup over cold sores. Stay away from foods that worsen symptoms. Acidic foods like citrus, tomatoes, or coffee can irritate cold sores and make symptoms last longer. Your doctor can help you get your cold sores under control and avoid potential complications. These may include ocular herpes, which happens when HSV-1 transfers to the eyes. Other complications can include various skin infections. Recap Oral or topical antivirals may shorten an outbreak. Keep the area clean and avoid foods that might irritate the sore. A cold compress can also help. Preventing Cold Sores If you have frequent outbreaks, your doctor may prescribe daily Zovirax or Valtrex to help prevent outbreaks. Depending on your triggers, you may also be able to prevent outbreaks without medication. For example, using sunscreen can help prevent outbreaks triggered by sun exposure. Summary Cold sores are caused by the HSV-1 virus. Once you contract this virus you will always carry it. Symptoms include blisters around the lips, nose, and cheeks, which eventually break and form an open sore. During your first outbreak, you may also have flu-like symptoms. Subsequent outbreaks tend to be milder. See a doctor if you have sores near the eyes, frequent cold sores, or if symptoms last more than 15 days. HSV-1 is very contagious. Avoid close contact with others and sharing personal items while you are having an outbreak. Some treatments can shorten the duration of cold sores. These include prescription oral antivirals and topical antiviral creams. Cold compresses and over-the-counter pain killers may also help. Keep the area clean and don't eat foods that may irritate your cold sore. You may be able to prevent frequent outbreaks with daily prescription medication. It also helps to avoid known triggers. A Word From Verywell Fortunately, cold sores tend to be harmless. They usually clear up within a few weeks. If you develop symptoms of a cold sore outbreak or if you have recurrent outbreaks, talk to your doctor. They can help you find the best treatment plan for your age, medical history, and lifestyle. Was this page helpful? Thanks for your feedback! Sign up for our Health Tip of the Day newsletter, and receive daily tips that will help you live your healthiest life. Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit 7 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Ramchandani M, Kong M, Tronstein E, et al. Herpes simplex virus type 1 shedding in tears and nasal and oral mucosa of healthy adults. Sex Transm Dis. 2016;43(12):756-760. doi:10.1097/OLQ.0000000000000522 Krissel JD, Bhatia A, Thomas A. Cold sore susceptibility gene-1 genotypes affect the expression of herpes labialis in unrelated human subjects. Hum Genome Var. 2014;1:14024. doi:10.1038/hgv.2014.24 Looker KJ, Magaret AS, May MT, et al. Global and regional estimates of prevalent and incident herpes simplex virus type 1 infections in 2012. PloS One. 2015;10(10):e0140765. doi:10.1371/journal.pone.0140765 Institute for Quality and Efficiency in Health Care. Cold sores: Overview. Montgomery-Cranny JA, Wallace A, Rogers HJ, Hughes SC, Hegarty AM, Zaitoun H. Management of recurrent aphthous stomatitis in children. Dent Update. 2015;42(6):564-6, 569-72. doi:10.12968/denu.2015.42.6.564 Crimi S, Fiorillo L, Bianchi A, et al. Herpes virus, oral clinical signs and QoL: systematic review of recent data. Viruses. 2019;11(5):463. doi:10.3390/v11050463 Harvard Health Publishing. Preventing cold sores. Additional Reading American Academy of Dermatologists. Cold sores: diagnosis and treatment.