Cold sores, or fever blisters, are a common and often painful viral infection usually caused by the herpes simplex virus type 1 (HSV-1). These fluid-filled blisters typically appear around the lips and mouth, causing significant discomfort and aesthetic concerns. While various treatments are available for managing cold sores, a novel, and promising approach involves using tranexamic acid, a compound commonly used in cosmetics to diminish skin discoloration caused by aging and sun exposure. Recent studies suggest that tranexamic acid can significantly accelerate the healing process of cold sores, offering a faster and more effective treatment option.

Understanding Cold Sores and HSV-1

Cold sores are primarily caused by HSV-1, although HSV-2, the virus responsible for genital herpes, can also cause oral lesions. Once someone is infected with HSV-1, the virus remains in the body indefinitely, lying dormant in nerve cells. It can reactivate periodically, resulting in cold sore outbreaks triggered by factors such as stress, illness, sun exposure, and hormonal changes.

Traditional Treatments for Cold Sores

Conventional treatments for cold sores primarily involve prescription medications such as acyclovir, valacyclovir, and famciclovir and the non-prescription drug Docosanol, which is not  considered “antiviral” as its activity is to block the virus from reaching the cells rather than directly affecting the replication functions of the virus. Additionally, over-the-counter creams and ointments can provide symptomatic relief by reducing pain and moisturizing the affected area. The conventional treatments have widely varying results for many people and often require several days to produce significant effects, leading many to seek more rapid and consistent solutions.

Tranexamic Acid: A Promising New Approach

For those acquainted with l-lysine, an amino acid believed to help reduce cold sore recurrences, tranexamic acid emerges as a compelling alternative. Known as TXA, tranexamic acid is a derivative of lysine and is gaining attention for its potential benefits in cold sore care. TXA has been widely used for over 40 years to help with melasma and other types of skin discoloration or hyperpigmentation. But recently its cosmetic effects have been applied to cold sores as well.

Practical Application and Usage

Tranexamic acid is available as oral tablets and injectable solutions for other applications. For cold sores, topical application is preferred due to its targeted effect on the affected area. Patients should apply tranexamic acid serum thoroughly to the affected area as soon as they detect initial symptoms, such as tingling or itching. Application is repeated 3-4 times per day, but it can be applied more often if desired – there are no issues of toxicity or side effects for topical application of TXA.


The incorporation of tranexamic acid into cold sore care represents a significant leap forward in managing this prevalent viral infection. By potentially providing rapid return to normal appearance, tranexamic acid offers a promising option for the many people who have not had good results from the traditional treatments. And for most people, avoiding the embarrassment of an ugly cold sore and returning to normal appearance and regular social activities are the most important factors.