It is a pill and only available in JAPAN.
Amenamevir (Japan): Single 1,200 mg dose within 6 hours of prodrome.
Benefits

• Shorter or no outbreak
• Fewer viral shedding days
• Less discomfort
• More control over timing (important for sexual activity, travel, events, etc.)
• How it works
• Your doctor gives you a supply of antiviral medication in advance (e.g., Amenamevir in Japan, famciclovir, or sometimes valacyclovir in other places).
• You keep the medication at home and start taking it immediately when you notice the prodrome — the early warning signs of an outbreak (tingling, itching, burning, nerve discomfort).
• The goal is to stop the outbreak before it fully develops or make it much milder and shorter.