Which administration route of acyclovir is indicated for treating herpes simplex encephalitis?

Acyclovir is primarily indicated for the treatment of herpes simplex encephalitis through the intravenous route due to the severity and urgency of this condition. Herpes simplex encephalitis is a critical and potentially life-threatening infection that affects the brain. In such cases, rapid and effective medication delivery is essential, making the intravenous route the preferred choice.

When administered intravenously, acyclovir achieves higher plasma concentrations, which are crucial for effectively combating the viral infection in the central nervous system. This route allows for quick absorption and immediate therapeutic effects, ensuring that the medication can cross the blood-brain barrier effectively, which oral or topical routes may not achieve in sufficient concentrations.

Other routes, such as oral, topical, or buccal, are typically not suitable for treating severe systemic infections like herpes simplex encephalitis. Oral acyclovir may be used for milder infections or prophylaxis but may not reach the required levels in the bloodstream quickly enough for serious cases. Topical and buccal forms are designed for localized treatment and do not provide the necessary systemic exposure required to address a serious condition affecting the brain. Thus, intravenous administration is clearly indicated for treating herpes simplex encephalitis.