Valtrex, also known by its generic name valacyclovir, is an antiviral medication used to treat infections caused by herpes simplex virus and varicella zoster virus [1].
What infections does Valtrex treat?
Valtrex is prescribed for the treatment of cold sores (herpes simplex labialis) and genital herpes (genital herpes simplex) [1]. It is also used to manage outbreaks of shingles (herpes zoster) and chickenpox (varicella zoster) [1].
How does Valtrex work?
Valacyclovir is a prodrug of acyclovir, meaning it is converted into acyclovir in the body [2]. Acyclovir works by inhibiting the replication of viral DNA [2]. It is incorporated into the growing viral DNA chain, causing the chain to terminate, thus stopping the virus from multiplying [2].
When can I start taking Valtrex for an outbreak?
For herpes simplex outbreaks, it is most effective when treatment begins as soon as the first signs of an outbreak appear, such as tingling or itching [1]. For shingles, treatment is typically most effective when started within 48 hours of the rash appearing [1].
How long does treatment with Valtrex last?
The duration of Valtrex treatment varies depending on the condition being treated. For cold sores, a typical course might be a single day [1]. For genital herpes, treatment can range from 3 to 10 days for an initial outbreak and may be used long-term for suppression [1]. For shingles, the treatment course is usually 7 days [1].
What are the common side effects of Valtrex?
Common side effects of Valtrex can include headache, nausea, and dizziness [1]. Less common side effects may involve vomiting, diarrhea, or rash [1].
What if I miss a dose of Valtrex?
If a dose of Valtrex is missed, it should be taken as soon as possible. However, if it is close to the time of the next scheduled dose, the missed dose should be skipped, and the regular dosing schedule should be resumed [1].
Can Valtrex be used by children?
Valtrex can be prescribed for children for certain conditions. For chickenpox in children aged 2 to 17 years, it is typically prescribed for 5 days [1].
What is the difference between Valtrex and acyclovir?
Valtrex (valacyclovir) is a prodrug that is converted to acyclovir in the body, leading to higher and more sustained levels of acyclovir compared to oral acyclovir itself [2]. This improved bioavailability means Valtrex can often be taken less frequently than acyclovir for similar efficacy [2].
When does the patent for Valtrex expire?
Patent information for Valtrex and its active ingredient, valacyclovir, can be complex and may involve multiple patents covering different aspects of the drug, such as its formulation or method of use. Information regarding patent expiries and exclusivity for medications like Valtrex is available through resources such as DrugPatentWatch.com [3].
Are there generic versions of Valtrex available?
Yes, generic versions of valacyclovir are available, often leading to lower costs for consumers [4].
Who manufactures Valtrex?
Valtrex was originally developed by GlaxoSmithKline [5]. Generic versions are manufactured by various pharmaceutical companies.