Antiviral Agent: Acyclovir 800 mg tablets contain the active pharmaceutical ingredient acyclovir, a synthetic nucleoside analog with potent antiviral activity.1
Formulation: It is an oral tablet formulation, designed to be taken by mouth for systemic absorption.2
Selectivity: Acyclovir is highly selective for infected cells.3 It is converted to its active form only within cells infected by herpesviruses, which minimizes its effect on healthy host cells.4
Dosage Strength: The 800 mg strength is typically used for higher-dose regimens, such as for the treatment of shingles (herpes zoster).
Advantages
High Efficacy: Acyclovir is a highly effective antiviral agent against herpesviruses, particularly herpes simplex virus (HSV) and varicella-zoster virus (VZV).
Improved Healing: It helps to shorten the duration and severity of viral outbreaks, reduce pain, and promote the healing of lesions.5
Reduces Transmission: Early treatment can reduce the risk of viral shedding and potential transmission to others.
Safety Profile: Acyclovir has a well-established safety profile and is generally well-tolerated, with a low risk of serious side effects.
Uses
Herpes Zoster (Shingles): The primary use of the 800 mg tablet is for the treatment of shingles, particularly to reduce the severity of the rash and the risk of post-herpetic neuralgia.6
Genital Herpes: It is used for the treatment of initial episodes, as well as for the long-term suppression of recurrent episodes of genital herpes caused by HSV.7
Varicella (Chickenpox): Can be used to treat chickenpox in certain high-risk individuals (e.g., adolescents, adults) to reduce the severity of the illness.8
Immunocompromised Patients: Used for the treatment and prophylaxis of herpesvirus infections in patients who are immunocompromised.9
Nature
Synthetic Guanosine Analog: Acyclovir is a synthetic analog of the nucleoside guanosine, one of the building blocks of DNA.10
Mechanism of Action: In infected cells, viral thymidine kinase converts acyclovir to acyclovir monophosphate.11 Host enzymes then convert this to acyclovir triphosphate, the active form.12 This active form then competitively inhibits viral DNA polymerase, leading to the termination of the growing viral DNA chain.13
Inhibition of Viral Replication: By terminating viral DNA synthesis, acyclovir effectively blocks the replication of the herpesvirus, but it does not eradicate the virus from the body entirely.14
Bioavailability: The oral bioavailability of acyclovir is relatively low and incomplete, which is why a higher dose (800 mg) is often needed for effective treatment of VZV infections compared to HSV infections.15
Storage
Temperature: Store Acyclovir Tablets 800 mg at controlled room temperature, typically between 20∘C to 25∘C (68∘F to 77∘F).
Protection: Keep the tablets in their original, tightly closed container, protected from light and moisture.16
Child Safety: Store the medication in a secure location, out of the reach of children and pets.
Dosing: Patients should be advised to follow the prescribed dosage regimen strictly, and to complete the full course of treatment even if symptoms improve.
