What Causes Herpes?

Herpes is caused by the herpes simplex virus. Both men and women can get herpes. It is very contagious and is spread through sexual and skin-to-skin contact.

Two types of herpes simplex virus infections can cause herpes, HSV-1 and HSV-2. Both cause cold sores on and around the mouth or cause genital herpes.

The virus spreads through skin to skin contact commonly when having vaginal sex, anal sex and oral sex. Once you have the herpes virus it stays in your body for life and symptoms can flare up at any time. This usually happens because certain triggers can ‘reactivate’ the virus, which is known as a ‘recurrence’.

Outbreaks of herpes are symptomatic. Symptoms, include burning, itching, stinging, tenderness and redness of the affected area as well as bumps or clusters of blisters (called vesicles) on the skin. These may then form ulcers or sores.

Dr Simran Deo Medical Editor

Medically reviewed by

Dr Simran Deo

Last reviewed: 09 Apr 2020

What Triggers Herpes?

It is not known exactly why certain things trigger a recurrence of herpes, but there are thought to be a number of triggers:

  • Hormonal changes - changes in hormone levels, for example at certain times of the menstrual cycle, or due to pregnancy, can trigger a herpes outbreak.
  • Sexual intercourse - insufficient lubrication during vigorous sex can cause friction and irritate the skin and trigger herpes symptoms, though this might not happen every time. Water-based lubricants (not oil-based, as they can weaken latex, the material that condoms are made of) can help to reduce friction.
  • Weakened immune system - a lowered immune system, as the result of, for example, HIV or certain treatments for cancer such as chemotherapy, can lead to outbreaks of herpes.
  • Surgery - trauma to the skin such as an operation on the genital area could trigger an outbreak of genital herpes.
  • Excessive sweating in the genital area
  • Stress - physical stress such as extreme tiredness (fatigue), and emotional stress such as anxiety and/or depression
  • Drinking too much alcohol
  • Exposure of the affected area to strong sunlight or ultraviolet light from sunbeds.

Certain foods that are high in an amino acid called L-arginine are also thought to trigger recurrences of herpes. Certain nuts (almonds, peanuts, cashews and walnuts); grains (oats, whole wheat, brown rice); caffeinated drinks, and chocolate contain this substance and could trigger outbreaks in some people.

How to Identify and Avoid Herpes Triggers

It is a good idea to keep a diary to identify what could be triggering your outbreaks of herpes. Noting any patterns in what you eat, your lifestyle (for example if you’re not getting enough sleep or are under stress), can help you to identify anything that might be contributing to outbreaks of the virus.

Good self-care is essential to a healthy life, but can be extra important in avoiding herpes triggers. Making sure that you take steps such as getting enough sleep, minimising stress, eating a balanced diet, and avoiding over-exposure to the sun and/or sun beds, can all help you to identify and avoid the things that may be triggering recurrences of herpes. Improving your physical and emotional well being helps to support your immune system, which in turn keeps you stronger and healthier and less prone to recurrences of herpes outbreaks.

Many sufferers find that it’s the first outbreak of herpes that is the worst. Recurrences tend to reduce in severity and frequency over time.

Triggers for herpes vary from person to person. If you think that something may be triggering a recurrence of genital herpes, speak to your doctor.

How Often can it Recur?

Genital herpes recurrence rates vary from person to person and it is difficult to predict. It can often recur around three to six months after the first episode, and then several times a year thereafter. This all depends on a number of different factors including the stress, health and wellbeing, lifestyle, and personal triggers. Women may also experience outbreaks due to hormonal changes at certain times of the menstrual cycle.

Treatment Options

There are prescription drugs available to treat herpes outbreaks and suppress recurrences. These do not cure herpes but can help you to manage the condition.

Antiviral treatments such as aciclovir and valaciclovir are used to suppress genital herpes outbreaks. If you experience six or more outbreaks of genital herpes a year then these low dose suppression therapies, taken orally every day, help to prevent further herpes outbreaks. They can be ordered online following a confidential online assessment by a doctor which involves filling in a questionnaire. The doctor can then determine if one of these suppression therapies is suitable for you.

Practising good self-care and adopting healthy lifestyle habits, as well as the option of taking drugs to suppress the virus, can all help to prevent future herpes outbreaks or reduce their frequency.

Patient Reviews