Cold Sore Treatment While Pregnant: A Safe, Practical UK Guide

Getting a cold sore during pregnancy can feel worrying. You might wonder whether it is safe to treat, whether it is better to leave it alone, or if it could affect your baby.

For most women, a cold sore on the lips or around the mouth is a reactivation of a common virus and is generally considered low risk during pregnancy. In many cases, it can be managed safely. However, it is still important to know which treatments are considered suitable during pregnancy, when you should seek medical advice and when a cold sore may need more than self care.

This guide explains the treatment options that may be suitable during pregnancy, when treatment is recommended, what is different about getting a cold sore close to your due date and how prescription antiviral medicines may be used if your GP, midwife or prescriber recommends them.

This information is for educational purposes only and does not replace individual medical advice. Treatment suitability depends on an individual clinical assessment, and your GP, midwife or prescriber will recommend the most appropriate treatment for you.

What Is a Cold Sore and the Herpes Simplex Virus, and Why Does Pregnancy Affect It?

Cold sores are caused by the herpes simplex virus, most commonly HSV 1. After the first infection, the virus remains inactive in the body and can become active again from time to time. Common triggers include stress, illness, sun exposure and hormonal changes.

A cold sore often starts with a tingling or itching sensation before small blisters develop, usually around the lips or mouth.

During pregnancy, changes to your hormones and immune system may make cold sores more likely to return or feel more noticeable than usual.

If you have had cold sores before becoming pregnant, having one during pregnancy is generally not considered harmful to your developing baby. This is different from a first ever herpes simplex infection during pregnancy, which should always be assessed by a healthcare professional as it may require a different approach to treatment.

Some women choose not to treat a mild cold sore during pregnancy. In many cases, an uncomplicated cold sore on the face will heal on its own over time. However, if your symptoms are severe, keep returning or you are unsure about the most appropriate treatment, speak with your GP, midwife, pharmacist or prescriber for advice.

Is It Safe to Treat a Cold Sore While Pregnant?

In most cases, yes. NHS guidance states that aciclovir and valaciclovir are generally considered suitable antiviral treatments during pregnancy when recommended by a healthcare professional. Aciclovir is commonly considered the first choice for treating cold sores during pregnancy, although it is always important to check with your GP, midwife, pharmacist or prescriber before starting any medicine.

Topical aciclovir cream is absorbed into the bloodstream in very small amounts, so very little reaches the rest of the body.

That said, safe does not always mean treatment is needed. If you have a mild, uncomplicated cold sore on your face, it may heal on its own over several days without antiviral treatment.

If the cold sore is uncomfortable, paracetamol can usually be used during pregnancy for pain or fever when taken as directed or as advised by your pharmacist or doctor. Simple home care, such as applying a cool compress, may also help ease discomfort.

Docosanol is available over the counter, but there is less information about its use during pregnancy than there is for aciclovir. If you are pregnant, speak with your pharmacist, GP or midwife before using it.

Famciclovir is not routinely recommended during pregnancy because there is less safety information available compared with aciclovir.

If you are unsure whether you need treatment, or if your symptoms are severe, keep coming back or are not improving, speak with your GP, midwife, pharmacist or prescriber. They can recommend the most appropriate treatment based on your individual circumstances.

Cold Sore Treatment Options During Pregnancy

Topical aciclovir cream is generally considered the first treatment option for a cold sore on the face during pregnancy because it works where it is applied and only very small amounts are absorbed into the bloodstream. It is usually most effective when applied at the first signs of a cold sore, such as tingling, itching or burning, before the blisters fully develop.

This guide does not include specific dosing information because the right dose and treatment plan during pregnancy should always be confirmed by your GP, prescriber or midwife. The most appropriate treatment can vary depending on your stage of pregnancy and your individual circumstances.

In some cases, oral antiviral tablets may be considered, particularly if you have frequent or severe outbreaks or if your healthcare team feels closer monitoring is needed. During certain stages of pregnancy, antiviral tablets may also be recommended under specialist medical supervision. Your healthcare professional will decide whether this treatment is appropriate following an individual clinical assessment.

Cold Sores vs Genital Herpes and Neonatal Herpes in Pregnancy: Why the Distinction Matters

It is common to worry about cold sores during pregnancy, but it is important to understand the difference between cold sores and genital herpes.

Genital herpes can be more significant during pregnancy, particularly around the time of delivery. If active genital herpes sores are present during a vaginal birth, there is a risk of passing the virus to the baby during delivery. Although this is uncommon, it can be serious. This is why a first genital herpes infection during pregnancy, especially in the third trimester, should be assessed promptly by your maternity team. Depending on your individual circumstances, they may discuss treatment and your delivery plan. Recurrent genital herpes is usually managed differently, and the risk of passing the virus to the baby is generally lower than with a first infection during pregnancy.

If genital herpes is a concern during pregnancy, your healthcare team may also advise using condoms to help reduce the risk of transmission.

A cold sore on the face is a different situation. Neonatal herpes is rare in the UK, and the main precaution comes after your baby is born. Newborn babies are more vulnerable to herpes infections during the first few weeks of life, so if you have an active cold sore, it is recommended that you:

• Avoid kissing your baby until the cold sore has completely healed.
• Wash your hands thoroughly before touching your baby, especially after touching the cold sore.
• Avoid letting the cold sore come into contact with your baby's skin.

These simple precautions can help reduce the risk of passing on the virus while your cold sore heals.

When to Contact Your GP or Midwife

Many cold sores during pregnancy can be managed with advice from a pharmacist. However, there are some situations where you should contact your GP, midwife or another healthcare professional instead of managing it yourself.

Speak to your GP or midwife if:

• You develop a cold sore or herpes infection for the first time during pregnancy, especially in the third trimester. A healthcare professional will need to assess whether this is a first (primary) infection or a recurrence, as they are managed differently. Some people may also experience flu like symptoms with a first infection.
• A cold sore develops close to your due date. Your maternity team can advise on the most appropriate care and, if needed, discuss any additional precautions around delivery.
• You think you may have genital herpes or have recently had sexual contact that may have exposed you to the virus. Arrange an assessment with your GP, midwife or local sexual health service.
• The cold sore spreads beyond the usual area, especially if it is near or affecting your eye, as this needs prompt medical assessment.
• You develop signs of a more widespread or severe infection, such as a fever together with multiple cold sores or widespread skin lesions.
• You have frequent or recurring cold sores during pregnancy. Your GP may discuss whether ongoing antiviral treatment is appropriate based on your individual circumstances.

Contact NHS 111 or seek urgent medical attention if you develop severe symptoms, such as significant swelling, signs of a spreading infection or if you feel generally very unwell alongside a cold sore.

If your newborn baby becomes unwell after birth or you are concerned they may have been exposed to the herpes virus, seek urgent medical advice immediately.

Preventing Outbreaks During Pregnancy

Although it is not always possible to prevent a cold sore, a few simple steps may help reduce the chance of an outbreak or make symptoms easier to manage:

• Try to manage stress where possible, as stress can be a trigger for some people.
• Use a lip balm with SPF if sunlight tends to trigger your cold sores.
• Maintain good hygiene, and avoid sharing cups, cutlery, towels or lip products while you have an active cold sore.
• Avoid touching a cold sore. If you do touch it, wash your hands straight away to help prevent spreading the virus to other parts of your body, including your eyes, or to other people.
• Get enough rest and eat a balanced diet to support your general health and wellbeing during pregnancy.

Cold Sore Treatment When Trying to Conceive (TTC)

If you are trying to conceive rather than already pregnant, it is still important to let your pharmacist, GP or prescriber know. This helps them recommend the most appropriate treatment based on your individual circumstances.

If you think you may be pregnant, or there is a possibility you could be pregnant, mention this before starting any treatment.

There is generally no need to avoid seeking advice or treatment for a cold sore while trying to conceive. The most important thing is making sure your healthcare professional has all the information they need before recommending treatment.

How Ordering Treatment Works

• Complete a short online clinical assessment, which usually takes just a few minutes. Make sure you mention if you are pregnant, breastfeeding or trying to conceive. You should also let the prescriber know if this may be your first herpes infection, if you have genital herpes, or if you have any recent exposure concerns.
• Your answers will be reviewed by a qualified, GPhC registered prescriber, who will take your pregnancy and medical history into account when assessing whether treatment is suitable.
• If treatment is considered appropriate, your prescription will be dispensed and sent from a UK regulated pharmacy.
• If online prescribing is not suitable for your situation, for example if this is your first herpes infection late in pregnancy, you will be advised to contact your GP, midwife or local sexual health clinic for further assessment. Where appropriate, they may recommend additional investigations or treatment.

Any prescribed medicine should only be used under the guidance of a qualified healthcare professional. Treatment suitability is assessed on an individual basis, and results can vary from person to person.

Pricing

Always check the live product page for current pricing and pack size before ordering, as prices and availability can change. Note that oral antiviral treatment during pregnancy should be discussed with a prescriber, GP or midwife rather than selected independently.