Cold Sore

Before we can issue your treatment medications you are required to complete a short medical assessment and select your preferred option. The assessment will help us prescribe the right medicines for you.

Cold Sore Medication Online

Your final treatment will be decided by our prescribers based on your medical assessment. You will be asked to select a treatment option from a list after completion of your medical assessment.


  • A prescription-only medication
  • Treats painful blisters across the mouth and lips
  • Helps cold sores heal faster

From £15.99

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  • Treatment for herpes if taken at an early stage
  • Will not fight herpes simplex virus when inactive and dormant
  • Prevent a sore from forming if used as a preventative

From £29.99

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What is a Cold Sore?

Cold sores are blisters which can appear on or around the mouth caused by the herpes simplex virus type 1 or 2 usually picked up during early childhood or the teenage years. Initially a cold sore will not show any physical symptoms but rather it will begin as a tingle, itch or burning sensation on the skin.

After this, small blisters or sores will begin to appear, filled with fluid. They can be mild or more severe, with some outbreaks lasting far less time than others. Cold sores tend to appear at times of lowered immunity or stress as, once the virus is in your body having passed through the skin, will lie dormant in your nerves until your immunity is weak enough to be overtaken by the virus.

How effective is the Cold Sore treatment?

Although cold sores can clear up after around 7-14 days on their own you can help them to heal more quickly and lessen discomfort through the use of antiviral treatments which, when used correctly, can either stop the sore coming out or shorten the life of it.

If the medication is used from the onset of a cold sore, usually within 48 hours, then it is more likely to have a greater effect. When taken after this time it is unlikely to play a role in the healing process.

If you experience regular outbreaks of cold sores you could be prescribed a course of treatment to help prevent them.

Is it safe to take Cold Sore treatments?

Cold treatments are perfectly safe in the majority of patients when taken as directed and for the appropriate length of time as needed In some situations there can be possible side effects whereby a patient could not safely use a cold sore medication such as acyclovir or valacyclovir.

These instances include someone suffering with kidney damage or kidney failure (though they may be able to take a lower dosage). Also, someone who has experienced an allergic reaction to any of the ingredients in the medication should avoid using these cold sore treatments.

If a woman is pregnant or breastfeeding, it may not be safe for the baby in either situation as the drug can pass through to the foetus or be secreted into the milk causing potential harm.

If you have any concerns at all about the safety of a treatment book a free, confidential online appointment with one of our Click Pharmacy experts who can help you choose the best medication for your situation.

What different Cold Sore treatments are available?

Acyclovir or valacyclovir are two of the main cold sore treatments on the market. Acyclovir has been on the market as a topical gel since 1982 and as a tablet since 1985 making it the longest standing medication available and considered highly reliable.

Aciclovir stops the virus from being able to multiply. Cells affected by the herpes virus absorb the acyclovir helping to prolong the antiviral activity lowering the length of a cold sore attack as well as the severity of it.

Valacyclovir is also an antiviral medication so works in a similar way to acyclovir though it has a higher bioavailability meaning more of it can be used by the body to attack the virus rather than simply working through the body and being broken down by the liver. It is one of the most commonly prescribed medications for the herpes simplex virus and, as with acyclovir, it has been around since the 1980s.

Can I buy Cold Sore treatments online?

Cold sore medications can be purchased online with a prescription. To be prescribed one of the treatments you need to fill in a brief health questionnaire which will be assessed by the doctors at Click Pharmacy who can then approve your request. This will be based on a number of factors including any other medications you take, the regularity and severity of your outbreaks and whether this particular treatment would be a safe option for you.

Does a Cold Sore treatment provide immediate protection?

These antiviral treatments work at fighting the virus as soon as they get into your system, though they can take a few days for any benefits or improvements to be noticed.

The treatments themselves will not stop the sore from being contagious and it will continue to be catching until it completely clears, but the medication can shorten the life span of the virus by up to 2 days.

What are the side effects of a Cold Sore treatment?

Side effects of cold sore treatments vary from product to product and patient to patient and depend on a persons’ tolerance level to a new drug. Where one person may experience no detrimental effects, another person may experience mild nausea, constipation or dizziness.

Some of the most common side effects of the antiviral treatments include nausea, vomiting and diarrhoea but should be mild enough not to cause you to stop taking the medication.

Confusion or changes in behaviour are very rare potential side effects of antiviral cold sore treatments but if you experience this, or any other more serious issues at all after taking medication, including allergic reactions to the ingredients, stop your doses and seek medical help right away.

Authored by

Last reviewed 11 April 2023

How to order medications from us

Order your medication in a few clicks. Our process is easy, fast and secure.

Step 1

Short Medical Assessment

Fill out a questionnaire so our prescriber can assess if the treatment is suitable for you.

Step 2

Select Preferred Medication

Choose the medication you require from the range offered by our online pharmacy.

Step 3

Next Day Delivery

Add delivery details and complete payment process.

Order before 15:00pm (Monday to Friday) for next day delivery