Aciclovir Cream for Genital Herpes and Cold Sores: UK Guide

STI Treatments

Aciclovir Cream for Genital Herpes and Cold Sores: UK Guide

Aciclovir cream is a topical antiviral treatment used for cold sores and mild genital herpes outbreaks. It works by stopping the herpes simplex virus from multiplying, which helps sores heal faster and can reduce the severity of an outbreak if applied early enough.

This guide covers how aciclovir cream works, when to use it versus tablets, how to apply it correctly, and where to get it in the UK.

What Is Aciclovir Cream?

Aciclovir cream (also spelled acyclovir) is a 5% antiviral cream applied directly to cold sores or herpes blisters. It’s available under the brand name Zovirax and as cheaper generic versions. In the UK, aciclovir cold sore cream can be bought over the counter at pharmacies without a prescription.

For genital herpes, aciclovir cream is sometimes used alongside oral tablets, though tablets alone are usually more effective for genital outbreaks.

What Does Aciclovir Cream Treat?

How to Apply Aciclovir Cream

1. Start as early as possible — ideally at the first tingle or itch, before blisters form. The earlier you apply it, the more effective it is.
2. Wash your hands before and after application.
3. Apply a thin layer to the affected area and surrounding skin.
4. Apply 5 times a day, approximately every 4 hours while awake.
5. Continue for 5 days, or up to 10 days if the sore hasn’t healed.
6. Don’t cover with plasters or bandages unless advised by your doctor.

For cold sores, many people find that applying at the tingle stage can prevent the blister from fully forming.

Cream vs Tablets: When to Use Which

The key difference is that cream treats the surface while tablets work from inside the body.

• Cold sores: Cream is usually sufficient. Apply at the first sign of tingling.
• Genital herpes (first outbreak): Tablets are strongly recommended. A first genital outbreak can be severe, and oral aciclovir tablets or valaciclovir are much more effective than cream alone.
• Genital herpes (recurrences): Tablets are preferred. Cream can be used alongside tablets but adds limited benefit on its own.
• Suppressive therapy: If you get frequent outbreaks (6+ per year), daily oral aciclovir or valaciclovir can reduce recurrence by 70-80%. Cream is not suitable for suppressive therapy.

BASHH guidelines recommend oral antivirals as first-line treatment for genital herpes. Cream is an option for cold sores but is not the best choice for genital outbreaks used alone.

Side Effects

Aciclovir cream is generally well tolerated. Side effects are uncommon and usually mild:

• Temporary stinging or burning at the application site
• Dry or flaking skin
• Itching
• Redness (contact dermatitis, rare)

Allergic reactions are very rare. If you develop swelling, difficulty breathing, or a severe rash, stop using the cream and seek medical attention.

Where to Get Aciclovir Cream in the UK

• Over the counter: Aciclovir cold sore cream (e.g., Zovirax) is available at pharmacies without a prescription. Typically costs £5-10.
• Prescription: For genital herpes, your GP or sexual health clinic can prescribe aciclovir cream (free on prescription).
• Online: Available from registered online pharmacies.

Read more: Aciclovir tablets | Valaciclovir | Genital herpes guide

Frequently Asked Questions

Does aciclovir cream cure herpes?

No. Aciclovir cream treats the symptoms of an outbreak but does not cure the underlying virus. Herpes simplex virus remains in the body permanently, lying dormant in nerve cells between outbreaks.

Can I use aciclovir cream on genital herpes?

You can, but oral tablets are more effective for genital outbreaks. If your doctor has prescribed cream for genital use, follow their instructions. For most people, tablets are the better choice.

How fast does aciclovir cream work?

If applied at the tingle stage (before blisters form), aciclovir cream can sometimes prevent the blister from developing fully. Once blisters have formed, it typically speeds healing by 1-2 days compared to no treatment.

Can I buy aciclovir cream without a prescription?

Yes, for cold sores. Aciclovir 5% cream (branded as Zovirax or generic equivalents) is available over the counter at pharmacies. The pharmacist may ask a few questions before selling it.

Can I use aciclovir cream while pregnant?

Aciclovir cream is considered low risk in pregnancy because very little of the drug is absorbed through the skin. However, always consult your doctor or midwife before using any medication during pregnancy.

Related reading

• Can You Get Herpes From a Toilet Seat?
• Can You Get Herpes From Kissing?
• Comprehensive Test: Chlamydia, Gonorrhoea and Herpes
• Cold Sores vs Syphilis Sores: How to Tell the Difference
• Genital Warts vs Herpes: What's the Difference?

Sources

• NHS — Sexual health conditions
• BASHH — UK clinical guidelines for STI management
• British HIV Association (BHIVA) — HIV treatment guidelines
• Terrence Higgins Trust — sexual health information
• UK Health Security Agency — STI surveillance data

Steve Page

Steve Page is a recognised expert on Sexually Transmitted Diseases (STDs) and STD treatments, having published numerous articles in peer-reviewed journals and presented his research at conferences around the world. He has an in-depth understanding of the latest medical research on STDs, and is an advocate for the development of new treatments and protocols to improve the health of those affected. In addition to his research, he has dedicated his career to understanding the causes and symptoms of STDs, as well as how to best treat those impacted.