Aciclovir is a medication used to treat genital herpes. Each tablet contains 400mg of the active ingredient aciclovir. If you have an outbreak of genital herpes, a doctor will usually prescribe you a 5 day course of 400mg aciclovir tablets to take 3 times a day. This will reduce the unpleasant symptoms and make you feel better.
15 tablet(s) / 400 mg - £18.00
30 tablet(s) / 400 mg - £23.00
30 tablet(s) / 400 mg - £23.00
45 tablet(s) / 400 mg - £27.00
168 tablet(s) / 400 mg - £40.00
What is aciclovir?
Aciclovir is an antiviral medication used to treat genital herpes. It is used to treat an outbreak of genital herpes, as well as to stop future outbreaks.
Aciclovir is also used to treat:
- chickenpox and shingles
- cold sores and other herpes simplex infections
- or stop herpes outbreaks from happening
Aciclovir is a generic medicine. It is the same as the branded medicine, Zovirax. They both contain the same active ingredient, aciclovir, and work in the same way but have different names. Branded medicines are generally more expensive than generic medicines.
Side effects and contraindications
Aciclovir can be taken by adults up to the age of 65. If you are over 65 years of age, you should speak to your doctor before taking aciclovir.
Common side effects of aciclovir include:
- feeling or being sick
- feeling faint
- feeling tired (fatigue)
- high temperature (fever)
- skin reaction when exposed to light (photosensitivity)
- stomach pain
Uncommon side effects of aciclovir include:
- hair loss
- itchy, hive like rash
Rare side effects of aciclovir include:
- increased liver enzymes
- allergic reaction
- effects on some blood and urine tests
- difficulty speaking
- feeling weak
- fits (seizures)
- hallucinations (seeing things)
- kidney problems
- liver inflammation
- low numbers of red blood cells (anaemia)
- lower back pain
- stiff neck and sensitivity to light
- yellowing of the skin and whites of the eyes (jaundice)
If you have any of these rare side effects you should stop taking them and see a doctor straight away.
Aciclovir is known to interact with some medicines, including:
- mycophenolate mofetil
You should tell your doctor about any prescription or non-prescription drugs you are taking before taking aciclovir, including herbal remedies.
If you want to find out more about aciclovir, please read the patient information leaflet.
Genital herpes is an infection commonly caused by the herpes simplex virus type 2 (HSV-2) but can also be caused by herpes simplex virus type 1 (HSV-1). HSV-1 often causes cold sores. Genital herpesis a sexually transmitted infection and is passed on through sex.
Aciclovir works by stopping the growth of the herpes simplex virus responsible for causing genital herpes. By stopping the virus from multiplying, it helps to reduce the symptoms and stop the infection from spreading.
You should speak to your doctor if you are pregnant, planning on getting pregnant, or breastfeeding before taking aciclovir.
Do not take aciclovir if you:
- are allergic to aciclovir or any other ingredients in the tablets
- have kidney problems
- have any neurological problems
Genital herpes is caused by the herpes simplex virus (HSV). The virus causes an outbreak of blisters in the genital or anal region.
The symptoms include:
- small red blisters that can be sore and open
- burning, itching, or tingling around the genitals
- pain when you pee
- an abnormal vaginal discharge in women
The treatment available for genital herpes is antiviral medicine which helps to control and stop outbreaks.
There are three main treatment options available, they are:
Valaciclovir is a pro-drug, that means your body converts it into aciclovir after you have taken it. Famciclovir is also an antiviral medicine used to treat genital herpes. It works best if it is taken as soon as you notice your symptoms appear.
As well as tablets, aciclovir is also available in a cream which is often used to treat cold sores. Aciclovir cream is not usually recommended to treat genital herpes. If you are not sure if you have herpes, you can take a genital herpes test at home.
The dosage of aciclovir you require will depend on whether you have genital herpes symptoms now. The usual dose for the first episode of genital herpes is 400mg 3 times per day for up to 10 days.
If you have more outbreaks after the first one, the 400mg is used 3 times a day for 5 days.
Aciclovir can also be used to prevent outbreaks. This is recommended for people who have 6 or more outbreaks in a year, or whose outbreaks are very severe when they happen. This is called suppression treatment. For this, 400mg is taken twice a day for 6 to 12 months.
You should take the tablets by mouth, swallowing them whole with a glass of water. Or, you can dissolve the tablet in a glass of water and stir before drinking. Take aciclovir as soon as possible after your symptoms have occurred.
While taking aciclovir tablets, it is important to drink plenty of water to help keep your kidneys working well. Because aciclovir can make you feel tired or drowsy, it may impair your ability to concentrate and react. If you are affected, do not drive or operate machinery.
There are no known interactions between aciclovir and alcohol, so drinking while taking aciclovir tablets should not affect your treatment. When you have an outbreak of genital herpes, it may be best to avoid excessive alcohol drinking to help your body fight and treat the infection.
If you take more aciclovir than you have been prescribed, you should speak to your doctor for advice. It is not usually harmful unless you take too much over several days.
If you forget a dose you should take it as soon as you remember, unless it is nearly time to take your next dose. In this case, skip the missed dose entirely. Do not take a double dose to make up for the missed dose.
Dr Kathryn Basford
Dr Kathryn Basford is a qualified GP who works as a GP in London, as well as with ZAVA. She graduated from the University of Manchester and completed her GP training through Whipps Cross Hospital in London.Meet our doctors
Article created: 16 Sep 2021
Last reviewed: 16 Sep 2021
Aciclovir (2021) NICE [accessed 25 August 2021]
Aciclovir 400mg Tablets Patient Information Leaflet (2019) EMC [accessed 25 August 2021]
Aciclovir for treatment of recurrent genital herpes simplex virus type 2 (2002) Clinical Infectious Diseases [accessed 25 August 2021]
Genital Herpes (2020) NHS [accessed 25 August 2021]
Herpes simplex virus (2020) WHO [accessed 25 August 2021]
(Reviews are for ZAVA UK)
You can treat genital herpes two ways. One treatment option is for when you experience an individual outbreak (acute therapy) and the other is treatment for when you need to avoid regular outbreaks (suppressive). Asda Online Doctor by ZAVA offers both types of treatment through a discreet, convenient service.