Medication features:

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


Available strengths:



Price £15.99

Includes free private prescriptions

In stock

Delivery Time


Expected delivery date:

Friday, 8 December 2023

If you order within:


Next Day Delivery

Next Day

Quick Assessment


UK Registered Pharmacy

UK Registered

Discreet & Confidential

Discreet &

  • Overview
  • FAQ
  • Side Effects
  • Patient Information Leaflet
  • Reviews

What is Aciclovir

Aciclovir treats painful blisters across the mouth and lips known as, cold sores. They can be irritating and sour and have an effect on the patient’s confidence.

How effective is Aciclovir?

Aciclovir is prescribed to help cold sores heal faster and works most effectively when used at the first sign of symptoms, whereas, if used once the blisters have come out, the medication may not work as well. It is also a beneficial treatment for anyone whose herpes recurs regularly as it works well as a suppression and prevention.

The first time you use the treatment, Aciclovir may seem to work more effectively when compared to follow-up treatments, but the benefits of further treatment may still be preferable for anyone who experiences more regular or longer-lasting outbreaks.

Can I buy Aciclovir Online?

To purchase Aciclovir without taking the time out to visit your GP, you can fill in our brief health questionnaire, which will help our doctors assess whether this is the correct treatment for you. If you are approved, you will receive a prescription and be able to buy your medication. Your prescription will then be sent out to you by next-day delivery.

Why choose Aciclovir?

As the longest-standing antiviral treatment for herpes, having been on the market as a topical medication since 1982 and as a pill since 1985, it has been shown to be safe to take daily for anywhere up to 10 years if needed. It has also been proven to lessen the time a patient suffers from a herpes outbreak making it a good way to deal with regular occurrences.

What is contained in Aciclovir?

The active ingredient in Acyclovir is Aciclovir PhEur.

The inactive ingredients are colloidal anhydrous silica, magnesium stearate, polyvidone, sodium starch glycollate.

How should I use Aciclovir?

Aciclovir tablets must always be taken as directed by your doctor, and if you feel uncertain how best to take them, then you can book a free appointment with a Click Pharmacy expert who can assist you. The dose will be different for different people and depending on the reason you are using it, for example, for treatment or prevention.

For cold sores, the usual dosage is as follows:

Treatment: 5 times a day every 4 hours for 5 to 10 days

Prevention: 4 times a day every 6 hours for up to a year as directed by your doctor

The tablets should be taken with water, with or without a meal, and if it is too hard to swallow, it can be dissolved and stirred into water though this is not the preferred manner for taking the medication.

When taking this treatment, ensure you drink plenty of water during the day to keep your kidneys working as effectively as possible. If you miss a pill, then depending on how close you are to your next dose, take it as soon as you remember. Continue to take your medication until you have finished the complete prescription to ensure you get the full benefit.

How does Aciclovir work?

Aciclovir is an antiviral medication. It works specifically on infected cells and stops infections of the skin and/or mucous membrane from spreading. It reduces the severity of the virus and helps it to heal faster, decreasing pain and other side effects of a cold sore, such as itching.

Aciclovir cannot kill the virus as once it is in your body, it lays dormant until it reactivates, but it does help to prevent viral infections in anyone with lowered immunity or else it treats outbreaks when they occur.

How long can I take Aciclovir for?

The medication is usually taken for 5 to 10 days though if necessary, it can be taken for anywhere up to 12 months if prescribed for prevention. Your GP or Click Pharmacy doctor will discuss this with you based on your health questionnaire.

What are the side effects of Aciclovir?

There can be side effects from any medication though not everyone will experience them. Common side effects with Aciclovir can include dizziness, nausea, stomach pains, diarrhoea, tiredness or headaches.

If you experience an allergic reaction to the product, which can manifest as anaphylaxis, including swelling of the tongue, lips or throat or difficulty swallowing and breathing, then get medical help right away and stop the medication.

Other Warnings to consider

Sensitivity to sunlight and UV light, such as that found in a sunbed, can occur in some instances when taking Aciclovir resulting in your skin burning more easily. As such, when using this treatment, wear sunblock each day to ensure this does not occur.

Aciclovir can interact negatively with other medicines, so ensure you tell your doctor or pharmacist if you are taking any other medication, including but not limited to:

  • theophylline
  • mycophenolate mofetil
  • cimetidine
  • probenecid

If you are, or you think you may be pregnant, or you are breastfeeding, then ensure you tell your doctor this information. There are limited studies done on the effects of Aciclovir in these instances, so it is important to get advice on this before going ahead with the medication.

What is genital herpes?

Genital herpes is a sexually transmitted infection. Herpes simplex virus (HSV) is the causative agent transmitted through skin-to-skin contact during sexual activity. Symptoms can include painful blisters in the genital area, fever, and swollen lymph nodes. Genital herpes is a chronic condition, meaning that once a person is infected, the virus remains in their body for life. While there is no cure for genital herpes, antiviral medications can help manage symptoms and reduce the likelihood of transmission to sexual partners. It is important for individuals who are sexually active to practice safe sex and get tested regularly for sexually transmitted infections, including genital herpes.

Can I buy Aciclovir tablets over the counter in the UK?

No, Aciclovir is a prescription-only antiviral drug, which a UK-registered doctor will prescribe you following a physical or online consultation.

Can I have sex whilst taking Aciclovir?

When experiencing a herpes outbreak or in between outbreaks, individuals with genital herpes can transmit the virus to their sexual partners. Avoid sexual activity during a flare-up. While using condoms can offer some protection against transmission, it is essential to note that this method is not foolproof.

Does taking Aciclovir Tablets affect my fertility?

There is no data that suggests taking Aciclovir Tablets affects fertility in any way.

Can I take Aciclovir Tablets if I have a kidney problem?

If you have any history of a new or existing kidney problem, consult a GP or pharmacist before taking Aciclovir Tablets.

How long does it take for Aciclovir Tablets to work?

These tablets can take up to 3 days to work effectively. After 3 days you should be able to notice symptoms fading.

Can I drive while taking Aciclovir Tablets?

A common side effect is dizziness, if you suffer from this you should avoid driving and using machinery until you feel better.

Can I drink alcohol while taking Aciclovir Tablets?

Yes, it is safe to drink alcohol while taking Aciclovir Tablets.

It is rare for this drug to cause any serious problems that affect vital parts of the body such as the kidneys and blood cells. To prevent this from happening you should drink plenty of water to remain hydrated while taking this medication.

Common side effects can include nausea, headaches, diarrhoea, and vomiting. Although these side effects are usually mild, if any of these side effects worsen seek medical advice.

Always read the patient information leaflet before starting your treatment. The patient information can be found here.

Return to Assessment