The Herpes Rash
How to recognise and manage this symptom
The herpes rash is a group of blisters around the mouth or genitals
The rash is caused by white blood cell activity in the infected area
There are other STIs and non-sexually-transmitted infections that can cause a similar rash
You can your rash diagnosed online, or by your GP if you prefer
There are treatments and lifestyle recommendations available for managing your rash
What is a herpes rash?
What it looks like – a herpes rash normally looks like a collection of small, fluid-filled blisters that appear around the mouth or the genitals. When these blisters pop, they will then scab over. The herpes rash is normally accompanied by other symptoms of a herpes infection, such as:
- A burning or stinging sensation on the skin before the rash appears
- Flu-like symptoms, such as a fever, headache, tiredness, weakness, or aches and pains
- Painful urination
Is it a serious problem? – getting a herpes rash is not a sign that something is seriously wrong. Almost 9 in 10 people who have the herpes virus on their body never realise it, but in people who experience symptoms the rash is one of the most common complaints that are reported. The rash also typically doesn’t last for the whole time you have an active outbreak: it takes a few days to appear and normally clears before some of the other symptoms have run its course.
When does this rash happen? – in a person who has the herpes virus on their body, the average frequency of outbreaks is four to five times per year. When a person is not experiencing an active outbreak, a very small number of the herpes virus stays on the body but lies dormant (doesn't do anything).
Why does herpes cause a rash?
Your body's immune system actually causes the rash – when the herpes virus infects the skin, the body’s immune system starts to attack the areas of the skin that are affected. This process can cause the appearance of a rash in some people who have been infected with the herpes virus.
The rash is caused by several things that happen on the skin:
- White blood cells start to attack the virus. A build up of white blood cells cause the appearance of blisters filled with a white, sticky fluid
- More blood flow is diverted to the areas of the skin affected, causing the skin to become red and warm. This happens because an increase in temperature can help kill the virus
- Irritation of the skin can cause the feeling of itch or even pain in some people
People with different immune systems get different symptoms – different people have different immune systems, which means that you may have a very different experience of herpes compared to another person. Some people may find that they do not normally get a rash when they experience an active outbreak of herpes – this is because it all depends on the body’s reaction to the virus.
Is it a herpes rash or something else?
If you've been exposed to herpes, it could be a herpes rash – if you have had sexual contact (including vaginal, oral, or anal sex) with a person who have been diagnosed with herpes and is experiencing an active outbreak, you are likely to have become infected. You can still become infected if you used a condom as an active outbreak of herpes is very contagious.
It could also be a different STI – other sexually transmitted conditions (STIs) can also cause a rash. For example, untreated syphilis can cause a red or brown rash on the skin. Also, HIV can cause a rash in some people. It can be very difficult to tell what kind of STI a person has based on the symptoms alone as some of them can be very similar to each other.
It could also be a different, non-sexually transmitted condition – a broader range of non sexually transmitted conditions can cause a rash. The most common non-STI cause of a rash is a fungal infection of the skin. This can take on different appearances depending on what species of fungus has grown on the skin. Some are painless, some might itch, and some can even be painful.
How do you diagnose a herpes rash?
Getting an online diagnosis (and treatment) – you can use our online photo assessment service to find out whether a rash on your skin is caused by herpes. This is available at any time so you can use it at your convenience. To use our online photo assessment service, follow these simple steps:
- Take two good quality photos of the affected area of skin
- Fill in a very short questionnaire which asks a few questions about the rash
- A doctor will review your questionnaire and photos and give you a diagnosis if they can and advise on treatment. In certain cases, they will also be able to prescribe the treatment and send it to your address by post
Can you do home testing? – no, it’s not possible to do home testing to diagnose a rash. This is because many different conditions can cause a rash and most testing kits are specific to a single condition. So, it’s not practical to try to diagnose a rash using a home kit.
Getting diagnosed in person – you can also make a face-to-face appointment with a doctor or nurse to get a diagnosis. Go to your GP practice or nearest sexual health clinic (sometimes known as GUM clinic) to make an appointment. In your appointment, you will be asked some questions about the rash as well as more general questions about your health. They may ask detailed questions about recent sexual contacts. After this, they will examine the affected area. Then, they will come to a diagnosis and advise you on the best course of treatment. They may write a prescription which you can give to any pharmacy. If the pharmacy has your medication in store, you can have it in minutes. If not, you should be able to collect your treatment the next day.
What can you do about a herpes rash?
Getting medical treatment – herpes is treated by a family of medicines called antivirals. You can order two different types of antivirals from us. These are called Aciclovir and Valaciclovir. Antivirals can help shorten the length of an active outbreak. If you experience pain on urination when you are experiencing an active herpes outbreak, you may be able to get creams to ease this.
Managing the rash – there are some things that you can do at home to help with an outbreak:
- Wash the affected area with plain or salty water to prevent from developing infections
- Apply vaseline if you experience pain
- Avoid wearing tight clothing which may irritate the skin
- Take regular pain relief such as paracetamol. Make sure that you follow manufacturer’s guidelines. Do not take other medications which also contain paracetamol such as cold & flu tablets and drinks
- Do not share towels with others
- Avoid having oral, vaginal, or anal sex until the rash clears up
Long-term treatment for repeat rash outbreaks – if you get six or more outbreaks in a year or the outbreaks affect you severely, you may be able to take antiviral medications for up to one year to prevent outbreaks from happening, this is called suppressive therapy.
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