Healthy Living

What Are the Symptoms of Cold Sores?

What Are the Symptoms of Cold Sores?

What are cold sores?

Cold sores or fever blisters are a very common perioral condition caused by the herpes simplex virus (HSV). There are two types of herpes simplex virus. Type 1 usually causes cold sores, although in some cases, the cold sores can also be caused by type 2. It is usually characterized by groups of tiny, fluid-filled blisters on the lips (common), nose, and mouth. The blisters can completely heal without leaving a scar, but they can recur any time.

The virus is transmitted through close contact such as kissing. Most people with cold sores had come in contact with HSV between 3-5 years old. However, they will not experience any symptoms until after their teenage years. Most people will come in contact with the herpes simplex virus at some point in their lives, but many will never experience symptoms. Once you catch the virus, it remains with you for life but might stay in the dormant stage. The body also develops an immune reaction that keeps the virus in check, preventing further outbreaks.

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When the herpes simplex virus invades the skin, it travels from the epidermis to the nerve roots, where it will become inactive. When the virus is triggered and reactivated, the virus will march into the cells of the outer layer of the skin, causing fluid-filled blisters to come out.

Symptoms of Cold Sores

Some of the symptoms of cold sores include:

  • Fever
  • Sore throat
  • Pain around the mouth and lips
  • Swollen glands in the neck, which indicate an infection
  • Drooling in some children
  • A blister or clusters of blisters around the mouth, cheeks, and nose

Stages of Cold Sores

There are five stages of cold sores, covering from the initial sign to full healing.

Prodromal Stage

The first sign of cold sores is the prodromal stage. This stage lasts for one to two days and will end when blisters appear. The prodromal period is experienced by 40-60 percent of patients.

During the prodromal stage, itching, tingling, erythema, inflammation, hypersensitivity, or soreness on the site where the blister will erupt is experienced. These symptoms are commonly experienced on the edges of the upper or lower lip. The skin in and around the cheeks and nose is the occasional target. Fever or malaise may also be experienced during the prodromal stage.

Blister Stage 

The next stage is the blister stage. Small, fluid-filled blisters now appear on the surface. In most cases, the blisters appear around the mouth, nose, and cheeks, but in very rare cases, blisters might show up in other parts of the body. At the end of the blister stage, the lips may be disfigured due to patches of blisters.

Weeping Stage 

After two days, the blisters will begin to rupture, which will then expose an open wound that will become gray in color. This stage is called as the weeping stage. During this stage, highly infective fluid, which is yellowish in color, comes out of the wounds.

Scabbing Stage

After a day or two, the wounds will be covered with yellow crusts. This is the start of the scabbing stage. This stage will last for two to three days. The scabs start to break and bleed, and the skin under the scab is pruritic and painful. When a scab is damaged, it will be followed by a smaller secondary scab.

Healing Stage

As the scabs gradually resolve, the patient goes through the healing stage. The secondary scabs gradually slough and reveal a pinkish skin that looks like the surrounding unaffected skin.

Cold sores seldom leave permanent scars on the affected site. Although the usual duration of cold sores is seven to ten days, the condition may last for as long as two weeks. When the blisters return, it will always be in the same spot where they started to appear.


It is best to begin treatment as soon as the first symptoms appear. Doing so reduces the duration of the condition and reduces the severity of the symptoms. The common treatment for cold sores is acyclovir, which is an antiviral cream. It must be applied to the blisters five times a day for five days. Acyclovir can be bought over-the-counter or can be obtained as a prescription drug. For recurrent and severe attacks of cold sores, anti-HSV agents are prescribed.


Cold sores or fever blisters are most commonly caused by the type 1 herpes simplex virus, but can also be caused by the type 2 herpes simplex virus in some cases. The symptoms often start off similar to the flu, which includes fever, sore throat, swollen lymph nodes, and finally, the appearance of blisters around the mouth, nose, and cheeks. In some rare cases, blisters might appear in other parts of the body. The type 1 herpes simplex virus is also commonly known as oral herpes.

The stage with the blisters is highly contagious, wherein the virus spreads quickly at this time. To prevent the spread of the virus, keep minimal contact with other people as much as possible during this stage, avoid touching your eyes or other parts of your body after touching a sore, and wash your hands thoroughly after touching a sore. Do not scratch the sores, but apply a balm or ointment using cotton on the affected area to soothe the itching.

The blisters start to crack open and release a clear to yellowish-colored liquid. The virus continues to be highly contagious at this stage. Avoid sharing utensils, towels, lip balms, and other personal items with anyone else during an outbreak.

Finally, the blisters start to scab over and the virus becomes less contagious once all the blisters have scabbed over. Eventually, all the scabs fall off revealing new skin underneath and very rarely leaving any scars.

There is no real cure for cold sores. Once the virus has been contracted, it remains in the body for life. However, the body’s immune system develops antibodies to keep the virus in check preventing future outbreaks and the spread to other parts of the body.

Some people who experience repeated outbreaks can seek medical help for various treatments such as oral antiviral tablets that can help reduce the severity of the symptoms or topically applied creams such as acyclovir, which help speed up the healing of the blisters by a day or so and make them less painful and itchy.

Prevention is always the best option and being vigilant with one’s health is important. If you have been infected with the herpes simplex virus or are in contact with someone who has the infection, then take a few precautionary measures mentioned above to prevent the spread of the disease.