Aciclovir

Key points

• Starting treatment as soon as an outbreak begins gives the best results, since the medicine limits how far the virus spreads to new cells.
• As a tablet taken systemically, it treats infection throughout the body rather than only at the skin’s surface, suiting genital herpes and shingles.
• Because the kidneys clear this medicine, doctors check kidney function beforehand and encourage good fluid intake during treatment.

What is Aciclovir?

Aciclovir is a pharmaceutical antiviral compound that targets herpes viruses specifically. It belongs to a class of medicines called nucleoside analogues, which interfere with viral replication. Several brands and formulations exist because herpes infections vary in location and severity, requiring different dosing approaches. The tablet form offers a convenient oral option for managing outbreaks at home.

What Aciclovir is Used For

Aciclovir is used for infections caused by the herpes simplex virus, including cold sores around the mouth and genital herpes. It is also prescribed for Varicella Zoster Infection, the virus responsible for shingles and chickenpox. Treatment works best when started early in an outbreak, as the medicine limits the virus’s ability to spread to new cells. Patients with recurrent Herpes Simplex episodes may use it to shorten the duration and severity of symptoms.

How Does Aciclovir Work?

Aciclovir works by blocking the virus’s ability to copy its genetic material, which it needs to multiply. Once inside an infected cell, the medicine is converted into its active form, which then gets incorporated into the growing viral DNA chain. This causes the chain to stop extending, effectively halting viral replication. For you, this means fewer new virus particles are produced, giving your immune system a better chance to control the infection and allowing sores or blisters to heal more quickly.

Aciclovir Brands and Forms

The tablet form of aciclovir is the most widely used oral formulation, offering straightforward dosing for patients managing herpes outbreaks. As part of the broader Antivirals category, aciclovir tablets are available under brand names such as Zovirax. The tablet format is suitable for systemic treatment, meaning it works throughout the body rather than being applied directly to a sore. This makes it practical for genital herpes and shingles, where the infection affects areas beyond the skin surface.

Safety Overview for Aciclovir

What to Check Before Using This Medicine

Before starting aciclovir, let your doctor know about any kidney problems, as the medicine is filtered by your kidneys and may require dose adjustments. Dehydration can also affect how the body processes the drug, so adequate fluid intake matters during treatment. Inform your healthcare provider of any other medicines you are taking, including over-the-counter products.

Possible Reactions and Tolerability

Most people tolerate aciclovir well, though some may experience mild stomach upset, headache or dizziness. Skin rash is a less common reaction that should be reported to a doctor. Staying well hydrated during treatment supports the kidneys in clearing the medicine from your system.

Interactions and Health Factors

Aciclovir can interact with other medicines that affect kidney function, potentially altering how either drug is processed. Your doctor will review your full medication list to identify any concerns before prescribing. Pre-existing kidney disease is the most significant health factor to discuss, as it directly influences dosing.

Product labelling and verified clinical sources remain the correct references for specific contraindications, interactions and reactions.

Further reading

• Acyclovir: MedlinePlus Drug Information
• ACICLOVIR 800 MG TABLETS BP
• Acyclovir - StatPearls - NCBI Bookshelf