Valacyclovir vs acyclovir: Everything you need to know
Dr. Aysha Butt is the Medical Director of FROM MARS, and is a GP Partner at Woodcote NHS Medical Practice.
Both meds work in a similar way. They stop the herpes virus from multiplying and spreading, but there are differences between them. So, if you have a herpes infection which is better for you?
Here we’ll let you know how the meds work, the differences and which is better, valacyclovir or acyclovir?
What is herpes?
Before we get on to acyclovir and valacyclovir a quick review of herpes.
Herpes is a virus. A family of viruses to be precise called herpes simplex viruses (HSV). They generally infect your skin and cause blisters and sores to form. If the infection is on your face we call it cold sores, if the infection is on and around your genitals we call it genital herpes.
Unfortunately there’s no cure for herpes. Once a herpes virus infects you it stays in your body for life. Most of the time it lies dormant in the nerve cells in your skin and you have no symptoms. Every once in a while the virus reactivates and you get another outbreak of sores, blisters and other symptoms.
Although herpes infections can’t be cured they can be managed with medications like valacyclovir and acyclovir.
What is acyclovir?
Acyclovir is an antiviral medication used to treat herpes infections. It works by stopping the virus from multiplying.
When you’re first infected or the herpes virus reactivates it spreads through your skin cells. The virus uses your cells’ natural DNA copying process to make copies of itself so it can invade and infect other cells.
Acyclovir stops this. It blocks an enzyme (called DNA polymerase) from working. The enzyme that’s needed to copy the virus’s DNA. It actually mimics this enzyme taking its place, but then working in a different way. This slows how fast the virus spreads and gives your immune system a better chance to clear it from your skin cells.
You usually take acyclovir by swallowing it as a pill. You can also buy creams that contain acyclovir that you apply directly to infected skin.
Acyclovir is the medical/generic name for the medication and you can also buy branded versions called Zovirax and Sitavig.
What is valacyclovir?
Valacyclovir is a similar antiviral medication to acyclovir. You take it to manage herpes infections – to reduce the severity of outbreaks and to prevent outbreaks from happening.
As with acyclovir you usually take valacyclovir as an oral pill. Valacyclovir is the medical/generic name for the medication and you can also buy a branded version called Valtrex.
Valacyclovir works in exactly the same way as acyclovir. It blocks the enzyme DNA polymerase from working, stopping the virus from copying itself. It works in the same way as when you use valacyclovir, your body actually converts it into acyclovir.
So, if your body turns valacyclovir into acyclovir are they effectively the same medication?
Nearly. There’s one key difference.
What’s the difference between acyclovir and valacyclovir?
Although valacyclovir is converted into acyclovir, valacyclovir appears to be the more effective medication.
This is because valacyclovir is absorbed into your body better than acyclovir. So even though valacyclovir becomes acyclovir in your body, you’re likely to get more of it into your system if you swallow valacyclovir rather than acyclovir.
Research has shown you can get the same or better results by taking valacyclovir instead of acyclovir. And because it’s absorbed better into your system you can take valacyclovir less often than acyclovir and still get the same or superior results. You typically take valacyclovir pills twice a day and acyclovir pills five times a day.
Acyclovir vs valacyclovir: which is better for you?
Everyone responds differently to medication and both drugs are effective, but you may get better results with valacyclovir than acyclovir.
What is the difference between acyclovir, valacyclovir and famciclovir?
Acyclovir is an antiviral drug that can treat herpes infections. Valacyclovir is a similar medication that also treats herpes infections. Once you take valacyclovir your body converts it into acyclovir before it gets to work. Your body absorbs valacyclovir more effectively than acyclovir though.
Famciclovir is also an antiviral medication that can also treat herpes. It’s a different drug to acyclovir and valacyclovir, but it works in a similar way. However, Famciclovir is more often used to treat shingles – a rash similar to chickenpox.
Is valacyclovir stronger than acyclovir?
Valacyclovir isn’t necessarily stronger than acyclovir, but it’s absorbed by your body more efficiently than acyclovir. This means more valacyclovir makes it into your system.
Can I take acyclovir and valacyclovir at the same time?
No, you shouldn’t take acyclovir and valacyclovir at the same time. Valacyclovir is converted inside your body into acyclovir, so if you take both you risk taking too much acyclovir. This can increase your risk of side effects, including serious ones like kidney damage. Only take one of these medications and always take it exactly as prescribed.
How long does it take for valacyclovir to start working?
Valacyclovir gets to work as soon as you start taking it. How quickly you see results will depend on the severity of your symptoms and how soon you take valacyclovir once an outbreak starts. In general it can provide pain relief in two to three days and can help you clear up outbreaks in around five days.
If you’re interested in trying valacyclovir or Valtrex you can order them directly FROM MARS.