If you have ever experienced a blister on your skin, you may have wondered if it was a cold sore or a sun blister. Both of these types of blisters can be painful, but they are caused by different things.

In this blog post, we will discuss the difference between cold sores and sun blisters, including their causes and treatments. We will also provide some tips for how to prevent them from happening in the first place. Keep reading to learn more about cold sores vs sun blisters: what is the difference.

What Are Cold Sores?

Cold sores, also known as fever blisters, are small and painful blisters that usually form on or around the lips. They are caused by the herpes simplex virus (HSV) and can be passed from one person to another through skin-to-skin contact or contact with infected saliva. 

Cold sores typically heal within two weeks without scarring. However, the virus that causes cold sores (HSV) can remain inactive in your body for long periods of time and can reactivate when you’re under stress or have a cold or the flu. There is no cure for cold sores, but there are treatments that can help shorten the duration of an outbreak. 

What Are Sun Blisters?

Sun blisters are different from cold sores in that they are not caused by a virus. Instead, they are caused by exposure to UV rays from the sun (hence the name). Sun blisters typically appear on sun-exposed areas of the skin like the face, neck, chest, hands, or arms.

They tend to be more common in people who have fair skin that burns easily. These blisters are usually only painful for a day or two and will go away on their own within a week. Anyone can get sun blisters if they spend enough time in the sun without proper protection. 

Causes And Symptoms Of Cold Sores And Sun Blisters

Cold sores are caused by the herpes simplex virus, which is easily spread through contact with an infected person. Sun blisters, on the other hand, are caused by exposure to ultraviolet light. 

The first time you are exposed to HSV-1, you may develop a fever, headache, or sore throat. Within a few days, small blisters will form around your mouth or nose. These blisters will eventually break open and crust over. Other symptoms of cold sores include: 

-Burning, itching, or tingling around the mouth or nose 

-Sensitivity to sunlight 

-Swollen lymph nodes 


-Body aches 

Sun blisters form when your skin gets too much UV exposure. This can happen if you spend too much time in the sun without wearing sunscreen or if you use a tanning bed excessively. The first symptom of sun poisoning is usually redness and swelling of the skin, followed by the formation of small fluid-filled blisters. Other symptoms of sun poisoning include: 





Cold Sore And Sun Blister Remedies

Whether you’re dealing with cold sores or sun blisters, there are several remedies that may help you feel better and speed up the healing process. Here are a few remedies to try: 

Over-the-Counter Medicines

Over-the-counter medications like ibuprofen and acetaminophen can help reduce pain and inflammation associated with cold sores or sun blisters. Lip balms containing SPF 30+ can be used to protect the lips from further irritation. There are also several antiviral creams that can be applied directly to the affected area, which will help it heal faster.

Cold Compresses

Cold compresses can help reduce the pain and inflammation of sun blisters or cold sores. Apply a cold compress to the affected area for 15-20 minutes at a time, several times a day. 

Aloe Vera

Aloe vera gel can help reduce the healing time of sun blisters and cold sores. It contains anti-inflammatory and antiviral properties that can help soothe the skin and reduce swelling. Apply the gel directly to the affected area several times a day until the blisters have healed.


Moisturizers can help keep skin hydrated and reduce the risk of further irritation. Apply moisturizer to the affected area several times a day to keep the skin soft and hydrated. 

Hydrocortisone 1 Percent Cream

Hydrocortisone 1 percent cream can help reduce inflammation, itching, and pain associated with sun blisters or cold sores. To treat your blisters, apply a thin layer of cream to the affected area twice daily until they have healed.

Prescription Treatments

In some instances, your doctor may prescribe a topical or oral antiviral medication to help expedite the healing process. These medications can help reduce pain, itching, and inflammation associated with cold sores or sun blisters. 

Use Luminance RED

Luminance RED is a revolutionary cold sore and sun blister treatment that helps reduce pain and itching while promoting rapid healing. This light therapy device uses near-infrared light to safely and effectively target the herpes viruses that cause cold sores and sun blisters. In a clinical study, Luminance RED was found to significantly reduce the severity and duration of cold sores and sun blisters. If you’re having trouble getting rid of your cold sores or sun blisters, Luminance RED may be the solution. 

Treatments To Avoid

It’s important to avoid scratching or picking at your cold sores or sun blisters, as this can cause further irritation and delay healing. In addition, avoid using rubbing alcohol or hydrogen peroxide, as these ingredients can be harsh on the skin. Also, avoid using steroid creams as they can cause further irritation and delay healing. 

Prevention of Cold Sore and Sun Blister

With a little bit of know-how, you can avoid these pesky problems altogether. Here are a few tips: 

Use Sunscreen

One of the best ways to prevent cold sores and sun blisters is to use sunscreen. This can be tricky because many sunscreens contain ingredients that can actually trigger cold sores. 

Make sure to use sunscreen with SPF 30 or higher and check the list of ingredients for potential triggers. And don’t forget to reapply every two hours, especially if you’re sweating or swimming. 

Don’t Touch

Another way to prevent cold sores and sun blisters is to avoid touching them. This may seem obvious, but it’s actually harder than it sounds. Cold sores are often located around the mouth, which means they’re easy to accidentally touch when you’re eating or talking. 

And sun blisters are often located on exposed areas like the nose or shoulders, which makes them tempting to pick at. So resist the urge to touch, and your skin will thank you! If you do touch them, make sure to wash your hands immediately afterward. This will help stop the spread of infection.

Use Ice

If you feel a cold sore or sun blister starting to form, reach for the ice! Applying ice to the affected area can help reduce swelling and pain. Just be sure to wrap the ice in a clean cloth, so you don’t cause further irritation. 

Trade-in Your Toothbrush

Finally, one of the best ways to prevent cold sores is to trade in your toothbrush for a new one every few months. This is because cold sores are caused by viruses, which can live on surfaces like toothbrushes. So if you’re using an old toothbrush, you could be re-infecting yourself every time you brush your teeth! 

When To Call A Doctor

If your cold sores or sun blisters don’t go away after several weeks, or if the cold sores start to spread to other parts of your body, it’s time to call a doctor. Your doctor can prescribe stronger treatments and rule out any serious underlying conditions. 

It’s also important to call a doctor if you notice signs of infection, like redness, swelling, or pus. These can be signs of a bacterial infection that needs to be treated with antibiotics. 

Tips to Speed Healing

If you’re looking for ways to speed healing, here are a few tips:

Keep The Area Clean

To keep your cold sores and sun blisters clean, use mild soaps or cleansers that won’t irritate your skin. Also, avoid using harsh scrubs or loofahs, as this can further aggravate the area.

Stay Hydrated

Staying hydrated is key for healing your skin. Make sure to drink plenty of water throughout the day, as this will help promote cell regeneration and speed up the healing process. 


Finally, make sure to get plenty of rest. Your body needs time to heal, so take a break from your normal activities and focus on getting some much-needed shut-eye. 

Frequently Asked Questions (FAQs)

Are heat blisters the same as cold sores?

No, heat blisters and cold sores are not the same thing. Cold sores are caused by the herpes simplex virus, while heat blisters are caused by prolonged exposure to a hot environment. 

Can sun blisters turn into cold sores?

No, sun blisters and cold sores are not related. Sun blisters are caused by overexposure to the sun or extreme temperatures, while cold sores are caused by viruses. 

How long do sun blisters on lips last?

Sun blisters on the lips can last anywhere from several days to several weeks, depending on how severe the burn is. In most cases, they will heal on their own within a couple of weeks. 

Can I go in the sun with a cold sore?

It’s not recommended to go in the sun with a cold sore, as this could increase your risk of developing sun blisters. If you must go out, make sure to wear sunscreen and avoid direct sunlight. 

How to protect your lips from the sun?

To protect your lips from the sun, make sure to wear a lip balm with SPF. This will help provide protection from harmful UV rays and keep your lips hydrated. Additionally, stay in the shade as much as possible and avoid direct exposure to the sun. You can also try wearing a wide-brimmed hat to help shield your face. 


Despite their similarities, there are some key differences between cold sores and sun blisters. Cold sores are contagious, while sun blisters are not. Cold sores are caused by the herpes simplex virus, while sun blisters are only caused by exposure to UV radiation from the sun.

While there is no cure for either condition, there are ways to help prevent both cold sores and sun blisters. You can also check our article on Benefits of Turmeric for Cold Sores.

Hope this article on cold sores vs sun blisters has been helpful in understanding the differences between these two conditions. With the right precautions, you can help keep yourself safe from both cold sores and sun blisters. Good luck!