Recommended Application Frequency for Xerese
Apply Xerese (acyclovir 5% and hydrocortisone 1% cream) to cold sores 5 times daily, approximately every 4 hours while awake.[1] Use a thin layer covering the entire sore and 0.5 inches of surrounding skin. Treatment typically lasts 5 days, starting at the first sign of a cold sore (like tingling or itching).[1]
How Much to Apply Each Time
One tube (5g) provides enough for a full 5-day course. Squeeze out about 0.25-inch (0.6 cm) ribbon of cream per application—roughly fingertip unit size. Avoid over-application to prevent skin irritation.[1]
When to Start and Stop Treatment
Begin as soon as symptoms appear for best results; it reduces healing time by about one day compared to placebo.[2] Stop after 5 days or if the sore heals earlier. Do not extend beyond 5 days without doctor advice.[1]
Common Mistakes and Tips
Patients often under-apply or start too late, reducing effectiveness. Wash hands before and after; avoid picking at the sore. It works on lips or face but not inside the mouth.[1] Store at room temperature.
Who Should Avoid or Adjust Use
Not for children under 12, immunocompromised patients, or those with eczema/herpes complications without doctor guidance. Pregnant or breastfeeding individuals: use only if benefits outweigh risks.[1] Possible side effects include dry skin, burning, or redness (usually mild).[2]
How Xerese Differs from Other Cold Sore Treatments
| Treatment | Active Ingredients | Frequency | Key Difference |
|-----------|---------------------|-----------|---------------|
| Xerese | Acyclovir + hydrocortisone | 5x/day | Adds steroid to reduce swelling/itch faster than antivirals alone [2] |
| Abreva (docosanol) | Docosanol | 5x/day | OTC, no prescription; shorter healing by ~0.5 days [3] |
| Zovirax (acyclovir only) | Acyclovir | 5x/day | No anti-inflammatory; similar antiviral effect [1] |
| Valtrex (valacyclovir pills) | Valacyclovir | 2x/day oral | Systemic; better for frequent outbreaks [3] |
Xerese requires a prescription and is FDA-approved for ages 12+.[1]
[1]: Xerese Prescribing Information (Medscape)
[2]: FDA Label for Xerese
[3]: Cold Sore Treatment Comparison (WebMD)