The 400 mg strength of acyclovir is like the "just right" bowl of porridge in the Goldilocks story - not too strong, not too weak, but often exactly what's needed for many viral conditions. This middle-dose option balances effectiveness with tolerability for millions of patients worldwide.
What Conditions Use 400 mg Strength?
Doctors frequently prescribe 400 mg tablets for:
- Genital herpes outbreaks - 3 times daily for 5-10 days
- Cold sore treatment - 3 times daily for 5 days
- Long-term suppression - Twice daily for 6-12 months
- Shingles in some cases - As part of combination therapy
Why 400 mg Hits the Sweet Spot
Feature |
200 mg |
400 mg |
800 mg |
Dosing Frequency |
5x/day |
3x/day |
2x/day |
Effectiveness |
Good |
Excellent |
Excellent |
Side Effects |
Rare |
Occasional |
More common |
Typical 400 mg Treatment Schedules
For Active Outbreaks
Take one 400 mg tablet:
- First dose upon noticing symptoms
- Then every 8 hours (e.g., 7am, 3pm, 11pm)
- With or without food
- Continue full course even if symptoms improve
For Daily Suppression
Take one 400 mg tablet:
- Every 12 hours (e.g., 8am and 8pm)
- At consistent times each day
- May continue for years under doctor supervision
What Makes This Dose Special?
The 400 mg strength offers unique advantages:
- Convenient dosing - Fits between meal times
- Proven effectiveness - Used in major clinical trials
- Good tolerability - Most people experience minimal side effects
- Cost-effective - Often covered by insurance
Patient Experiences with 400 mg
"The 400 mg dose three times daily worked perfectly for my genital herpes outbreak. By day 3, the pain was gone." - Rachel, 29
"I've taken 400 mg twice daily for prevention for 2 years with no outbreaks and no side effects." - James, 42
Important Safety Information
- Kidney function matters - Dosage may need adjustment
- Stay hydrated - Helps prevent rare kidney issues
- Watch for interactions - Especially with other nephrotoxic drugs
- Don't crush tablets - Unless directed for swallowing difficulties
For complete prescribing information about this dosage, see acyclovir 400 mg details from medical professionals.
Frequently Asked Questions
Can I split 400 mg tablets?
Only if scored - but check with your pharmacist first as it may affect absorption.
What if I miss a 400 mg dose?
Take as soon as remembered unless near next dose time - never double up.
Is 400 mg safe for elderly patients?
Often yes, but may require adjustment based on kidney tests.
Key Benefits of 400 mg Strength
- Reduces outbreak severity by 70-80% when started early
- Convenient 3-times-daily dosing for treatment
- Twice-daily option for prevention
- Available as affordable generics
