Aciclovir 400mg medication to treat and prevent recurrent genital herpes outbreaks available to buy online from Dr Fox.

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Buy Aciclovir online in UK

How to order Aciclovir online for UK delivery:

  1. Read medical information about genital herpes treatment
  2. Answer medical questions to check for eligibility
  3. Reviewed by doctors - posted from UK pharmacy (tracked 24hr service)


Herpes antiviral medicationQuantityCost
Aciclovir 400mg15 tablets (1 course of treatment)£8.95
Aciclovir 400mg30 tablets (2 courses of treatment)£13.95
Aciclovir 400mg168 tablets (3 months suppressive treatment)£29.20
Aciclovir 400mg336 tablets (6 months suppressive treatment)£49.40

Price match guaranteePrice match guarantee
Prescription issued online - small prescription fee per order.

Compare prices: Dr Fox prices are 25%-50% lower cost than other online clinics.

Prescription fees

Dr Fox supplies medicine on prescription and charges a small prescription fee based on the order value of each prescription.

Prescriptions are issued by our doctors online and sent electronically to our pharmacy.

Order valuePrescription fee
up to £10£1.00
up to £20£2.00
up to £40£3.00
over £40£4.00

If you have your own private or NHS paper prescription please post to our pharmacy (details).

Dr Fox prices are 25%–50% lower than other UK online clinics.

Comparative costs of genital herpes treatment from UK online clinics (07 April 2021) - qualifying notes
*Dr Fox adds a small prescription fee not included in table above.
  1. The prices shown are listed by the online clinics named after a customer first enters consultation information and is offered prescriptions. It is possible these clinics may have special offers or lower prices for repeat supplies.
  2. Prices may change and are, to the best of our knowledge, accurate on the date stated. All products in stock and new condition.
  3. Dr Fox does NOT claim to provide a superior service to any of the online clinics listed. All the clinics listed, as far as we can tell, comply with all regulation and, as far as we can tell, operate to high ethical standards.
  4. Dr Fox adds a small prescription fee not included in the table (between £1 and £4 depending on value of the order).
  5. To amend the information in this table please contact us
  6. The prices listed in the table do not identify the cost of prescription medicine as online clinics charge a single fee to cover services which includes advice, consultations, prescriptions and dispensing and supply of treatments.
  7. Where services include free delivery this is using the slowest delivery option available. Dr Fox uses Royal Mail Tracked 24.
Herpes antiviral medicationDr Fox*ZavaSuperdrugSimple PharmacyLloydsIndependent Pharmacy
Aciclovir 400mg (1 course)£8.95£19.95£20.00£14.95£20.00£19.99
Aciclovir 400mg (2 courses)£13.95£24.95£25.00£19.95£25.00£31.98
Aciclovir 400mg (3 month course)£29.20£49.00£49.00£34.95£45.00£48.00
UK delivery£2.90includedincluded£3.20included£2.95

Delivery charges

UK delivery only: £2.90 per consultation via Royal Mail 24 Signed For (1-3 working days with tracking).

Parcel forwarding services are not permitted. Use only UK home or work delivery address.

Returns and refunds - unwanted items can be returned within 14 working days for a full refund.

About Aciclovir

Aciclovir is sometimes also spelt as Acyclovir and is better known by the original brand name Zovirax. Aciclovir tablets are an antiviral medication. The tablets reduce herpes virus growth and spread. A 5-day course of aciclovir 400mg tablets will typically reduce the duration of genital herpes sores by one or two days and also reduce severity of symptoms and infectivity. If taken early enough aciclovir may prevent sores from breaking open. Taking aciclovir twice daily for 6-12 months can prevent (suppress) herpes outbreaks.

The best-known brand of aciclovir is Zovirax. A number of different pharmaceutical companies make generic aciclovir, which is medically the same as Zovirax, but at lower prices. Dr Fox pharmacy supplies lower cost generic aciclovir (see generic medicines FAQs).

Aciclovir is also used to treat other herpes family virus infections, particularly chickenpox, shingles, cold sores, and herpes family virus infections in immunocompromised patients. The dose and strength of aciclovir prescribed depends on the specific type of infection being treated.

For further information see NHS - Aciclovir (including Zovirax).

What is genital herpes?

Genital herpes is the name given to sores occurring in the vaginal area or on or around the penis caused by herpes viruses. Genital herpes includes herpes sores in the region of the anus (back passage). It is similar to cold sores which are herpes sores on the lips or around the mouth. Genital herpes used to be caused mostly by HSV2 (herpes simplex virus type 2) and cold sores by HSV1 (herpes simplex virus type 1). However there is now a lot of overlap - HSV1 genital herpes tends to cause fewer recurrent episodes than HSV2. Because of this it can sometimes be helpful to know which of the two herpes simplex viruses is causing your outbreaks - a doctor or STI clinic can take a swab to determine this.

Herpes viruses spread from person to person, usually by unprotected sex, or sometimes by kissing or orogenital sex.

Not every sore in the genital area is caused by herpes. It is important to see a doctor or STI clinic to have a diagnosis and to be tested for other sexually transmitted infections. Do NOT self-treat with antiviral medication without getting a medical diagnosis first.

For further information see NHS - Genital herpes.

Below are photos of herpes blisters:

Photos of herpes blisters

More photos of herpes on genitalia from DermNet NZ.

What is recurrent genital herpes?

First infections with the herpes virus typically produce a small blister rapidly followed by a painful sore. A sore is an inflamed area of broken skin, usually a few millimetres across. Sores usually last a few days (5 to 10 days), during which time there are often also flu-like symptoms (fever, no energy, irritable). The sores then heal up. However, the herpes virus stays in the body close by and the infection and the sore can break-out again from time to time. New break-outs are similar to first infections, although usually less severe. New sores occur in the same place as before. New sores in different places are unlikely to be caused by herpes.

Can I have sex whilst taking aciclovir?

During a flare up, and possibly in-between, a person with genital herpes is infectious and can spread the herpes virus to sexual partners. It is best to refrain from sexual contact during an outbreak of herpes. Using condoms provides protection from transmission, but this protection is not 100% effective.

How does aciclovir treat genital herpes?

The aim of treatment is to reduce the severity and duration of the sores by taking antiviral medication each time a new sore breaks out. The most commonly prescribed antiviral medication is aciclovir tablets. Tablets should be started as early as possible once symptoms (tingling, pain) start, preferably within the first 24-48 hours. A course of treatment lasts 5 days.

Alternatively, people who get frequent or very severe outbreaks of their genital herpes can take preventive treatment. This involves taking 400mg aciclovir twice a day for between 6 and 12 months

Aciclovir is not the only antiviral medication. There are alternative antivirals for herpes, namely famciclovir and valaciclovir. These work in the same way as aciclovir, but are less commonly prescribed. They are NOT available from Dr Fox.

Does aciclovir medication cure genital herpes?

A course of aciclovir, or other antiviral medications, does not eliminate the herpes virus completely or prevent future outbreaks. The herpes virus remains in the body after an outbreak, usually for many years, and will continue to produce sores from time to time. There may be months or years between outbreaks of the sores. Sores may break out more when a person is tired or run down, but often there is no pattern to outbreaks. They usually become less frequent over time.

How to take aciclovir medication

Repeat genital herpes: the standard dose for the treatment of recurrent genital herpes is one aciclovir 400mg tablet three times daily for 5 days.

Suppression of genital herpes: the standard dose of treatment for suppression therapy is one aciclovir 400mg tablet twice a day for an initial period of 6 months but can be taken up to 12 months.

Swallow tablets whole with plenty of fluids, or dissolve in a glass of water. Can be taken with or without food.

Please note: The dose instruction in the patient information leaflet supplied with the tablets is different from the instruction on the packet - follow the prescription instruction label on the box. BNF/NICE recommended dose for Aciclovir to treat 'Genital herpes simplex, treatment of recurrent infection' is 400 mg 3 times a day for 3–5 days.

One course of treatment for genital herpes is 15 tablets (3 tablets daily for 5 days), and two courses will be 30 tablets. Because medicine boxes come in sizes of 56 tablets these must be split up and supplied in blank boxes of 15 or 30 tablets. This is common practice in pharmacies and nothing to be concerned about.

Recommended aciclovir dose for suppression is 400mg twice a day - this will be supplied in original medicine boxes of 56 tablets.

The dosage for cold sore treatment is different to genital herpes treatment.

Other strengths and doses of aciclovir can be prescribed for treating other types of recurrent herpes infections. See your doctor if the standard treatment is not effective or there are new symptoms or side effects.

It is important to drink plenty whilst taking aciclovir.

Missed doses can be taken late – but avoid double dose and do not exceed daily dose.

Can anyone take aciclovir?

People over 65 years, and those diagnosed with kidney disease (impaired renal function) and women who are pregnant or breastfeeding may not be able to take aciclovir. Checks are carried out during the Dr Fox online consultations and advice is given. Dr Fox pharmacy supplies medicine to adults only (over 18s). If you are aged under 18 please contact your GP or a local sexual health clinic for testing and treatment.

If you experience a bout of herpes during pregnancy or while breastfeeding, visit your doctor to discuss treatment options.

Aciclovir tablets and other medication

People taking the following medications should consult a doctor or pharmacist before taking aciclovir:

  • Probenecid (used to treat gout).
  • Cimetidine (used to treat stomach ulcers).
  • Mycophenolate mofetil (used to stop your body rejecting transplanted organs).
  • Ciclosporin (an immunosuppressant drug).
  • Theophylline (used in asthma and other breathing problems).
  • Zidovudine (used in HIV infection).

Side effects of Aciclovir

Like all medicines, this medicine can cause side effects, although not everybody gets them.

Allergic reactions (may affect up to 1 in 1,000 people). If you have a severe allergic reaction, stop taking Aciclovir 400mg tablets and contact a doctor (or telephone 999 in the UK) straight away. The signs may include:

  • Rash, itching, or hives on your skin.
  • Swelling of your face, lips, tongue, or other parts of your body.
  • Shortness of breath, wheezing, or trouble breathing.
  • Collapse.

Other side effects

Common (may affect up to 1 in 10 people):

  • Headache
  • Feeling dizzy
  • Feeling or being sick
  • Fever/fatigue
  • Diarrhoea
  • Stomach pains
  • Rash
  • Skin reaction after exposure to light (photosensitivity)
  • Itching

Patient Information Leaflet

Illustration of patient leaflet from medicine packet

The Patient Information Leaflet (PIL) is the leaflet included in the pack with a medicine and must be read before taking the medicine. It is written for patients and gives information about taking or using a medicine.

Aciclovir 400mg patient leaflet

Dr Tony Steele

Authored 26 February 2020 by Dr Tony Steele
MB ChB Sheffield University 1983. Former hospital doctor and GP.

Reviewed by Dr B. Babor, Dr C. Pugh, Dr A. Wood, Dr P. Hunt
Last reviewed 07 April 2021
Last updated 18 October 2021


Product reviews

Aciclovir 400mg tablets rated 4.79/5 in 28 product reviews

See over 35,000 service reviews of Dr Fox

Aciclovir 400mg tablets

Fantastic fast and effective

08/06/2022 17:21
A. Baines Verified

Aciclovir 400mg tablets

Really helps with breakouts which has benefited me both mentally and socially. Couldn't recommend this service more.

11/04/2022 09:55
Anonymous Verified

Aciclovir 400mg tablets

Great, works quickly!

24/03/2022 08:59
Anonymous Verified

Aciclovir 400mg tablets

Quick delivery

02/03/2022 10:11
Anonymous Verified

Aciclovir 400mg tablets

Does as prescribed, quick delivery and very helpful.

01/03/2022 09:08
Anonymous Verified

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