Understanding Cold Sore Stages, Symptoms, And More

Medical reports show that around 48% of the American population has herpes simplex virus type 1 (HSV–1), the virus responsible for cold sores. You get the virus upon coming into contact with the saliva, sores, or any other bodily fluid of an infected person.¹

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Almost half of the American population has HSV–1, and many people living with the virus lead a healthy, symptom-free lifestyle. A flare-up occurs when the body's immune system drops, hormones change, or you expose yourself to the sun or cold for an extended period.

Usually, these sores clear up within 7–10 days, even without medication. For stubborn, painful, and recurrent cold sores, your doctor may prescribe topical anesthetics, anti-inflammatory drugs, or antiviral ointments to control the virus.

What causes cold sores?

Fever blisters, as they are sometimes known, are caused by HSV–1, which affects almost 67% of the world's population. Mainly, the virus spreads through skin-to-skin contact with an infected person. You can also get the HSV–1 virus through oral sex or sharing utensils, makeup, and towels with a person with herpes simplex.³ ²

How do cold sores form?

Unlike many viral infections, HSV–1 remains asymptomatic for many people. That means you might not experience any symptoms while living with the virus. In case of a flare-up, symptomatic HSV–1 causes painful sores around the mouth, swollen neck lymph nodes, fever, and general body aches.

Normally, the symptoms show up when the body gets subjected to extreme stress, sudden hormonal changes, and extended exposure to direct sunlight. Furthermore, cold sores erupt when you get extreme fatigue, infections like influenza, and a compromised immune system.

What do the cold sore stages look like?

What are the stages of a cold sore? Typically, cold sores present in five major stages — telltale tingling, blistering, ulcer eruption, scab formation, and healing. Each of the cold sore stages has varying signs.

Stage 1: Telltale tingling

In this stage, you experience a prickling sensation around the mouth, specifically on the lips. The sensations can be accompanied by other uncomfortable symptoms like itching, tightness, and soreness that can last for 24 to 48 hours.

Stage 2: Blistering

A day or two after experiencing the prickling sensation, blisters develop along the lips. The vesicles have clear fluid, and the area underneath the blister appears red. Cold sores can also appear in the oral cavity, nose, eyes, and other body parts — not just the lips.

Stage 3: Ulcer eruption

The blisters rapture on the fourth or fifth day, leaving red, shallow, open sores. Since the third stage is the most contagious, you should avoid sharing utensils or kissing to minimize transmission. Furthermore, you should avoid touching your eyes and genitals since the fever blisters could spread to these parts.

Stage 4: Scab formation — crusting

After breaking out, the body begins repairing the open shallow wound. Typically, the sore dries up to form a crusty, brown scab that keeps foreign bodies out of the sore. As the crust shrinks, the area around it feels itchy and uncomfortably tight. The healing sore cracks and bleeds at times, especially when scratched.

Stage 5: Healing

Healing is the last phase of stages of a cold sore — occurring between 8–10 days after experiencing the first symptom. In this phase, the scabs start flaking away, exposing the new skin underneath.

Cold sore stages: Identification and treatment

A fluid-filled blister on the lips is the most common sign of oral herpes. Although fever blisters appear on the lips, you can have them on other body parts like fingers, eyes, cheeks, fingertips, genitals, and the nose.

Diagnosing a cold sore

Health providers use polymerase chain reaction (PCR) to confirm the presence of the virus causing cold sores.⁴

Besides PCR, health professionals can also use blood testing to diagnose the presence of herpes. However, it is not a recommended approach for people without symptoms.⁵


The key to reducing the chances of infecting loved ones is to ensure they do not come into contact with an infected person's saliva and bodily fluids. Some practical ways to eliminate contact include:

  • Washing hands frequently

  • Not sharing lip balm

  • Avoiding close contact

  • Avoiding sharing towels, straws, and toothbrushes

  • Cleaning utensils thoroughly before use

Treating a cold sore

Cold sores clear up on their own within ten days for people with a strong body defense system. Nevertheless, if you have compromised immunity or want to recover quickly, use the following treatment options to expedite recovery:

  •  Lemon balm: A 2008 study indicates that lemon balm accelerates the healing of cold sores. According to the report, the lemon balm contains potent antivirals that prevent the multiplication of HSV–1 virus.⁶

  • Antiviral medications for cold sores: Cold sore drugs like valaciclovir are formulated to help the immune system fight the herpes simplex type 1 infection by preventing the virus' ability to reproduce.

  • Over-the-counter cold sore cream: Cold sore creams like Abreva (containing 10% docosanol) expedite the healing of cold sores by relieving symptoms like itching and tingling. The cream is readily available over the counter.⁷

When to see a doctor

Unlike many viral infections, you can manage cold sores at home using over-the-counter medications and home remedies. However, if you experience recurrent flare-ups, you need to see a doctor for a comprehensive diagnosis and drug prescription. You should see a doctor if the cold sore:

  • Does not clear within two weeks

  • Spreads to other body parts

  • Comes along with a fever

  • Oozes excessively

The lowdown

Almost half of American citizens live with HSV–1, which causes cold sores. However, the virus remains dormant for people with a good immune system, often showing no signs. It only erupts when the body's immune system weakens, or hormones change abruptly.

The dormant HSV–1 also erupts due to excessive fatigue, exposure to sunlight, and infections. Whatever the cause, cold sores should clear up by themselves within ten days or earlier if you use antivirals to quicken recovery.

Frequently asked questions

How do I know what stage my cold sore is in?

You can know the stage depending on the appearance of the cold sore. For stage 1, the patient experiences a tingling sensation on the lips, and for stage 2, the patient experiences fluid-filled blisters. In stage 3, the blisters erupt. In stage 4, the outbreak scabs, and in stage 5, the scabs peel off.

Why are my cold sore outbreaks getting worse?

The sores worsen when exposed to acidic foods like soda, citrus fruits, and vinegar. Furthermore, a cold sore could worsen when hormones change, an illness compromises your immunity, or you spend more time exposed to direct sunlight.

What is the last stage of a cold sore?

The last stage of a cold sore is healthy healing. In this phase, the scab peels off, exposing new skin. For people with strong immunity, the healing process starts around days 8–10.

Why am I suddenly getting more cold sores?

You get more cold sores if you subject your body to extreme physical stress, experience hormonal changes, and expose yourself to hot sun or strong wind for extended hours. Furthermore, you get more cold sores if you undergo surgery or your immunity gets weakened by an infection.

  1. Prevalence of herpes simplex virus type 1 and type 2 in persons aged 14–49: United States, 2015–2016 | Centers for Disease Control and Prevention

  2. Fever blisters & canker sores | National Institute of Dental and Craniofacial Research

  3. Herpes simplex virus | World Health Organization

  4. Polymerase chain reaction for the diagnosis of herpesvirus infections in dermatology (2020)

  5. Genital herpes screening FAQ | Centers for Disease Control and Prevention

  6. Inhibitory activity of Melissa officinalis L. extract on herpes simplex virus type 2 replication (2008)

  7. Docosanol | NIH: National Library of Medicine

Other sources:

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