From the Guidelines
For shingles, acyclovir is typically prescribed at a dose of 800 mg five times daily for 7-10 days, with treatment starting as soon as possible after symptoms appear, ideally within 72 hours of rash onset, as recommended by the most recent guidelines 1.
Key Considerations
- The treatment duration may be extended to 10-14 days for older adults or those with compromised immune systems.
- Alternative antiviral medications for shingles include valacyclovir and famciclovir, which may offer better compliance due to fewer daily doses.
- Acyclovir works by inhibiting viral DNA synthesis, preventing the herpes zoster virus from replicating and spreading to new cells.
Important Details
- Treatment should begin as soon as possible after shingles symptoms appear to reduce pain and speed healing.
- Adequate hydration is important while taking acyclovir to protect the kidneys.
- Side effects may include nausea, headache, diarrhea, and dizziness.
Recommendations for Special Populations
- For immunocompromised patients, antiviral therapy is recommended for HZ, with oral valacyclovir or famcyclovir as the preferred treatment for uncomplicated cases, and intravenous acyclovir for complicated cases 1.
- Treatment should be prescribed within 72 hours of rash onset and continue for a minimum of 7-10 days.
From the FDA Drug Label
In a double-blind, placebo-controlled study of immunocompetent patients with localized cutaneous zoster infection, acyclovir (800 mg 5 times daily for 10 days) shortened the times to lesion scabbing, healing, and complete cessation of pain, and reduced the duration of viral shedding and the duration of new lesion formation In a similar double-blind, placebo-controlled study, acyclovir (800 mg 5 times daily for 7 days) shortened the times to complete lesion scabbing, healing, and cessation of pain; reduced the duration of new lesion formation; and reduced the prevalence of localized zoster-associated neurologic symptoms (paresthesia, dysesthesia, or hyperesthesia) The recommended dose and length of treatment for shingles with acyclovir is:
- Dose: 800 mg 5 times daily
- Length: 7 to 10 days Treatment was most effective if started within the first 48 hours of rash onset 2.
From the Research
Acyclovir Dosage and Duration for Shingles
- The recommended dosage of acyclovir for shingles is 800 mg, taken five times daily 3.
- The typical duration of acyclovir treatment for shingles is 7 to 10 days 4, 5, 3.
- One study found that oral acyclovir therapy for 10 days at a dosage of 800 mg five times per day was superior to a 400 mg five times per day dose schedule in shortening the period of viral shedding and accelerating the time to healing 3.
- Another study compared 7 days of acyclovir therapy with 21 days of therapy and found that the longer duration did not provide significant benefits over the standard 7-day treatment 5.
Efficacy of Acyclovir in Reducing Pain and Postherpetic Neuralgia
- Acyclovir has been shown to reduce the duration and severity of acute pain associated with shingles 6, 3.
- However, acyclovir does not appear to influence the incidence of postherpetic neuralgia (PHN) 4, 5.
- Other antiviral agents, such as valaciclovir and famciclovir, have been found to be more effective than acyclovir in reducing the risk of PHN and herpes-zoster-associated pain 7.