Find a doctor online with hub.health telehealth appointments in Australia
Find a doctor online with hub.health telehealth appointments in Australia

What is a Cold Sore Caused By?

can cold sores, small blisters, cold sore virus

As the seasons come and go, one thing seems to linger with its unwelcome appearance – cold sores. These pesky, painful blisters can be inconvenient, but understanding what causes them is the first step towards effective treatment of cold sores and prevention. This article delves into the mysteries of cold sores, shedding light on the factors that trigger their appearance. Whether you’ve experienced them before or are curious about this common condition, read on to learn more about what causes cold sores and how to tackle them head-on.

What is a Cold Sore?

Before diving into what causes cold sores, let’s clarify what a cold sore is. Cold sores, also called fever blisters, are small, fluid-filled blisters that typically appear on or around the lips but manifest on the nose, cheeks, or chin. They are caused by the herpes simplex virus (HSV), with the most common strain being HSV-1. This highly contagious virus affects a substantial portion of the global population and remains dormant in the nerve cells until triggered.

What do Cold Sores Look Like?

Symptoms of cold sores begin as a tingling or burning sensation in the area where they will eventually develop. This is often referred to as the prodromal stage. Shortly after, small, painful, and fluid-filled blisters emerge. The blisters might appear singly or in clusters and can cause discomfort and sensitivity. Over time, the blisters burst, leaving behind open sores that scab over before eventually healing.

Cold sore symptoms can take up to two weeks to fully heal; during this time, they are highly contagious. It is essential to avoid direct contact with the sores and refrain from sharing personal items like lip balms, towels, or utensils to prevent the virus from spreading.




If you’re looking for the easiest way to get cold sores treated, hub.health offers fast and convenient access to cold sore treatment, ordered online and delivered to your door. Start a consultation with our medical team today!




The Science Behind Cold Sore Activation

Cold sores are primarily caused by the herpes simplex virus (HSV), which exists in two main types: HSV-1 and HSV-2. HSV-1 is more commonly associated with cold sores, while HSV-2 is typically responsible for genital herpes. However, both types can cause cold sores in the mouth or genital area.

The herpes simplex virus (HSV), responsible for cold sores, can persist in a dormant state within the human body. Once the virus enters the body through a mucous membrane or a break in the skin, it travels to the nerve cells near the spinal cord and enters a latent phase. During this phase, the virus remains inactive and does not cause any symptoms or visible outbreaks.

Latency: The Quiet Period

In its latent or dormant state, the HSV hides from the body’s immune system, making it challenging for the immune system to detect and combat it effectively. Instead, the virus remains within the nerve cells, where it establishes a long-term residence. This period of dormancy can last indefinitely, with the virus laying low and biding its time.

Triggers: Waking the Dormant Virus

Despite its quiet demeanour, the HSV can be roused from its slumber and become active again. Various internal and external factors often trigger this reactivation. Once activated, the virus travels back along the nerve pathways to the original site of infection, leading to the appearance of cold sores.

The Role of Triggers in Reactivation

While the precise mechanism behind HSV reactivation is not entirely understood, several common triggers have been identified:

  • Weakened Immune Systems: When the immune system weakens due to illness, stress, or fatigue, the virus can exploit this vulnerability and begin its replication process.
  • Ultraviolet (UV) Radiation: Prolonged exposure to sunlight or other sources of UV radiation can prompt the reactivation of the virus, leading to cold sore outbreaks, particularly in the lip area.
  • Hormonal Fluctuations: Hormonal changes, such as those occurring during menstruation, can influence the immune system and provide an opportunity for the virus to resurface.
  • Injuries or Trauma: Physical injury to the mouth area, such as a cut or a burn, can disrupt the nerve cells and trigger the virus’s reactivation.
  • Fever and Illness: The body’s response to a fever or other infections can weaken the immune system and allow the virus to emerge from its dormant state.

It is important to note that not everyone who carries the herpes simplex virus will experience cold sore outbreaks. Some individuals may remain asymptomatic carriers, never displaying any visible signs of infection. However, those who do experience cold sores often find that these triggering factors influence their frequency and severity.

Managing and Preventing Cold Sores

Cold sores can be frustrating and uncomfortable, but the good news is that there are several strategies you can employ to manage and prevent outbreaks. By understanding the triggers that activate the herpes simplex virus (HSV) and adopting a proactive approach to your health, you can significantly reduce the frequency and severity of cold sore episodes.

Antiviral Medications for Cold Sores

Antiviral medications are one of the most effective ways to treat cold sores and shorten their duration. When taken at the first sign of a cold sore outbreak or during the prodromal stage (the tingling or burning sensation before the blisters appear), antiviral medications can help suppress the replication of the herpes simplex virus. Commonly available as topical creams or oral tablets, these medications can speed up healing and alleviate discomfort.

Strengthening Your Immune System for Defence

A robust immune system is your body’s frontline defence against viral infections, including HSV. To bolster your immune response, prioritise a healthy lifestyle. Engage in regular physical activity, maintain a balanced diet rich in vitamins and minerals, get adequate sleep, and manage stress effectively. Keeping your immune system in peak condition can better prevent cold sore outbreaks.

Sun Protection and Skincare

Excessive exposure to sunlight and harmful UV radiation can trigger cold sores in susceptible individuals. Protect your lips and the surrounding areas using lip balms or creams with SPF when outdoors. Additionally, avoid prolonged sun exposure, especially during peak hours, to reduce the risk of cold sore activation.

Coping with Stress to Keep Cold Sores at Bay

Stress is a well-known trigger for cold sores. Practice stress-reduction techniques such as meditation, yoga, deep breathing exercises, or engaging in hobbies that bring joy and relaxation. By managing stress effectively, you can help prevent cold sore outbreaks.

Learn nine ways to help manage your mental health.

Navigating Hormonal Fluctuations

Hormonal changes, particularly during menstruation, can influence the reactivation of the herpes simplex virus. Discuss potential management strategies with your healthcare provider if you notice a pattern of cold sores coinciding with your menstrual cycle. Hormonal therapies or antiviral medications taken preventively reduce outbreaks during these times.

Handling Mouth Area Injuries with Care

Accidental injuries can trigger cold sores, such as cuts, burns, or bites around the mouth area. Take precautions to avoid injury, and if an injury occurs, keep the area clean and use topical treatments to prevent infection.

Coping with Fever and Infections

A fever or other infections can weaken the immune system, leading to cold sore reactivation. Take prompt action to manage illnesses, and consult your healthcare provider if necessary.

Practical Tips for Minimising Cold Sore Outbreaks

Managing cold sores involves identifying and addressing the triggers that activate the herpes simplex virus (HSV). By understanding your triggers and making conscious lifestyle choices, you can take charge of your cold sore outbreaks and reduce their frequency and severity. Here are some practical tips to help you minimise cold sore outbreaks and regain control of your well-being:

Keep a Cold Sore Journal:

Start by keeping a record of your cold sore outbreaks and any potential triggers that might be associated with them. This journal can help you identify patterns and determine which factors activate the virus.

Practice Sun Protection:

UV radiation is a known trigger for cold sores. Protect your lips and face from sun rays by using lip balms or creams with SPF and wearing a wide-brimmed hat outdoors.

Reduce Stress with Relaxation Techniques:

Stress can weaken the immune system and increase the likelihood of cold sore outbreaks. Incorporate stress-reduction techniques such as meditation, deep breathing exercises, or engaging in activities that bring joy and relaxation.

Get Adequate Sleep:

Prioritise sufficient sleep each night to support a healthy immune system and improve overall well-being. It may be helpful to brush up on the importance of good sleep hygiene.

Eat a Balanced Diet:

To strengthen your immune system, consume a diet rich in vitamins, minerals, and nutrients. Include foods with lysine, an amino acid known to suppress the herpes simplex virus, such as fish, chicken, and legumes.

Consider Supplementation:

If you struggle to meet your nutritional needs through diet alone, consult a healthcare professional about potential supplements that may support your immune system.

Limit Alcohol and Tobacco Use:

Alcohol and tobacco can weaken the immune system, making it easier for the herpes simplex virus to reactivate. Reducing or eliminating their use can benefit your overall health.

Practice Good Hygiene:

Wash your hands frequently, especially during a cold-sore outbreak, to prevent the spread of the virus to other parts of your body or others.

Avoid Trigger Foods:

Some may notice that certain foods, such as chocolate, nuts, or citrus fruits, trigger cold sore outbreaks. Pay attention to your diet and determine if any particular foods affect you.

Use Lip Balms and Moisturisers:

Keeping your lips moisturised can help prevent them from becoming dry and cracked, reducing the likelihood of cold sore activation.

Monitor Hormonal Changes:

If you suspect hormonal fluctuations are linked to your cold sore outbreaks, consider discussing hormonal management options with your healthcare provider.

Be Prepared for Cold Sore Emergencies:

Keep antiviral medications or over-the-counter cold sore treatments on hand to use at the first sign of an outbreak. Prompt action can often reduce the severity and duration of cold sores.

Consulting a Healthcare Professional: When to Seek Medical Advice

Most mild cold sores can be managed with self-care measures and over-the-counter treatments, like cold sore creams and cold sore patches. However, there are certain situations when seeking medical advice from a healthcare professional is essential. Here are some scenarios where consulting a healthcare provider is recommended:

Severe or Frequent Outbreaks

If you experience frequent or severe cold sore outbreaks that significantly impact your daily life, it’s essential to consult a healthcare professional. They can help identify potential triggers, recommend appropriate treatments, and help you to manage recurrent outbreaks.

Compromised Immune System

If you have a weakened immune system due to medical conditions such as HIV/AIDS, cancer, or undergoing immunosuppressive therapy, cold sores can pose a more significant risk. Seeking medical advice is crucial to ensure proper management and prevent potential complications.

Cold Sores in or Near the Eyes

Cold sores in or near the eyes can be a serious medical concern and require immediate medical attention. Infections in this area can lead to eye damage and vision problems.

Cold Sores That Don’t Heal

If a cold sore does not show signs of improvement or healing within two weeks, a healthcare professional should evaluate the sore to rule out other potential causes.

Allergic Reactions to Cold Sore Treatments

If you experience an allergic reaction or adverse side effects from cold sore treatments, stop using the product immediately and seek medical advice for appropriate alternatives.

Underlying Medical Conditions

If you have underlying medical conditions or take medications, consult your healthcare provider before using any new treatments to ensure they do not interact negatively with your current medications or health status.

Emotional Distress

If cold sores significantly impact your emotional well-being or self-esteem, discussing your concerns with a healthcare professional can provide guidance and support.

Recurring Cold Sores in New Locations

If you experience cold sores in new or unusual locations on your body, a medical evaluation is necessary to rule out other potential causes or conditions.

While most cold sores are manageable with self-care and effective cold sore treatments, seeking medical advice under specific circumstances is crucial for your overall health and well-being. A healthcare professional can provide personalised recommendations, identify potential underlying issues, and offer strategies to manage cold sores effectively. Remember, your healthcare provider supports your journey toward better health and can help you make informed decisions about your cold sore management and overall wellness.




If you’re looking for the easiest way to get cold sores treated, hub.health offers fast and convenient access to cold sore treatment, ordered online and delivered to your door. Start a consultation with our medical team today!

Find a doctor online with hub.health telehealth appointments in Australia

Here at hub.health we are committed to everyone getting the best out of every moment.

Love yourself!

Read more

Brenda – 35

from $26.00 for 3 months

Dianne – 35

from $34.00 for 1 month

Eleanor

from $23.00 for 4 months

Estelle

from $23.00 for 3 months

Evelyn

from $23.00 for 4 months

Femme 100/20

from $23.00 for 4 months

Femme 150/30

from $23.00 for 4 months

Lenest 20ED (3)

from $23.00 for 3 months

Lenest 30ED (4)

from $20.00 for 3 months

Levlen

from $26.00 for 4 months

Loette

from $40.00 for 3 months

Logynon (b)

from $28.00 for 3 months

Madeline 150/30

from $18.00 for 1 month

Marvelon

from $18.00 for 1 month

Microgynon 20/100

from $55.00 for 3 months

Microgynon 30

from $35.00 for 4 months

Microgynon 50

from $23.00 for 4 months

Microlut

from $23.00 for 4 months

Micronelle 100/20

from $20.00 for 3 months

Micronelle 150/30

from $20.00 for 4 months

Monofeme

from $20.00 for 4 months

Nordette

from $30.00 for 4 months

Noriday 350mcg 4×28 Tab

from $23.00 for 4 months

Norimin

from $25.00 for 4 months

Petibelle

from $87.00 for 3 months

Primolut N

from $30.00 for 1 month

Qlaira

from $88.00 for 3 months

Seasonique

from $70.00 for 3 months

Slinda

from $79.00 for 3 months

Trifeme (a)

from $23.00 for 4 months

Triphasil 28 4×28 Tab

from $35.00 for 4 months

Triquilar (b)

from $33.00 for 4 months

Valette

from $84.00 for 3 months

Yasmin

from $80.00 for 3 months

Yaz

from $80.00 for 3 months

Zoeley

from $80.00 for 3 months