The herpes blisters will quickly merge and rupture, causing a painful sore known as an ulcer.
After drying and crusting over, the sore will gradually heal.
While HSV-1 and HSV-2 are incurable, antiviral drugs can reduce the severity and duration of outbreaks.
Illustration by Tara Anand for Verywell Health
A first outbreak may take longer to heal.
Many people who get HSV-1 will never have symptoms but still carry the virus and can infect others.
You may also experienceprodromal symptoms.
These are generalized and non-specific symptoms that develop before the main symptoms of an illness appear.
Others may experience prodromal symptoms without developing an actual cold sore.
The blisters may itch and be painfully sensitive to the touch.
The infection can also spread to other parts of your own body.
This is known asauto-inoculation.
After a few days, the sore will start to dry out and form a crusty scab.
The scab can be extremely itchy and may even crack.
Try not to bite or pick at the scab as this can lead to bleeding and infection.
It can also delay healing.
However, you should see a healthcare provider if:
What Causes Cold Sores?
Cold sores are sparked by the HSV-1 virus, which is very contagious.
Once infected, you’ll have the virus for the rest of your life.
You won’t have symptoms unless the virus is reactivated.
Not everyone with a cold sore experiences subsequent outbreaks.
In most cases, the symptoms will be less severe than the first outbreak.
How Cold Sores Are Spread
Cold sores are potentially infectious until they are completely healed.
If you have a cold sore, wash any surfaces you touch.
Common household cleaners likeLysolcan readily kill the virus.
How Cold Sores Are Treated
Cold sores are painful, annoying, and possibly embarrassing.
The earlier they are started, the more effective they are.
These may ease some discomfort but won’t lessen the severity or duration of the outbreak.
Depending on what your cold sore triggers are, you may be able toprevent outbreakswithout medications.
For example, you’re able to use sunscreen so you don’t get too much sun exposure.
Or it’s possible for you to practice meditation or breathing exercises to better manage stress.
It’s also important to practice safer sex.
HSV-1 can be passed through oral sex and cause genital herpes.
Condoms help but don’t entirely erase the risk.
If you have a cold sore or feel one coming on, it is best to abstain from sex.
Summary
Cold soresare mainly because of the HSV-1 virus.
Your first cold sore outbreak may be accompanied by flu-like symptoms.
Subsequent outbreaks tend to be milder.
2019;11(5):463. doi:10.3390/v11050463
Institute for Quality and Efficiency in Health Care.Cold sores: overview.
doi:10.1016/j.idcr.2019.e00512
American Academy of Ophthalmology.Herpes simplex virus keratitis: a treatment guideline - 2014.
2015;10(10):e0140765.
doi:10.1371/journal.pone.0140765
Lin Q, Lim J, Xue K et al.Sanitizing agents for virus inactivation and disinfection.View.
2020;1(2).
doi:10.1002/viw2.16
Harvard Health Publishing.Preventing cold sores.
American Academy of Dermatologists.Cold sores: diagnosis and treatment.
