How Long Does Impetigo Last?
Quick Answer
Impetigo lasts 1–3 weeks. With antibiotic treatment, it typically clears in 7–10 days. Without treatment, it can persist for 2–3 weeks or longer.
Typical Duration
Quick Answer
Impetigo typically lasts 1–3 weeks depending on treatment. Antibiotic therapy — either topical or oral — shortens the duration to about 7–10 days, while untreated cases can linger for 2–3 weeks and risk spreading to other body areas or other people.
Treatment Comparison
| Approach | Duration | Details |
|---|---|---|
| Topical antibiotics (mupirocin) | 7–10 days | Applied 2–3 times daily; first-line for mild cases |
| Oral antibiotics (cephalexin, dicloxacillin) | 7–10 days | Used for widespread or bullous impetigo |
| No treatment | 2–3+ weeks | Lesions may spread; risk of complications |
| Antibacterial washes only | 2–3 weeks | May reduce spread but does not treat infection |
Types of Impetigo and Duration
There are two main forms of impetigo, and each follows a slightly different timeline:
| Type | Appearance | Typical Duration |
|---|---|---|
| Non-bullous (most common, ~70%) | Honey-colored crusts on red sores | 1–2 weeks with treatment |
| Bullous | Large fluid-filled blisters | 2–3 weeks with treatment |
| Ecthyma (deep form) | Painful ulcers with thick crusts | 3–4 weeks; may scar |
Non-bullous impetigo is the most common form, caused primarily by Staphylococcus aureus or Streptococcus pyogenes. Bullous impetigo, caused exclusively by S. aureus, tends to take slightly longer to resolve.
Healing Timeline
| Day | What to Expect |
|---|---|
| Days 1–2 | Start antibiotics; keep sores clean and covered |
| Days 3–4 | Sores stop spreading; crusts begin to dry |
| Days 5–7 | Crusts fall off; new skin forms underneath |
| Days 7–10 | Most lesions fully healed; no longer contagious 48 hours after starting antibiotics |
| Weeks 2–3 | Residual pink marks fade; no scarring in most cases |
Contagious Period
Impetigo is highly contagious until 48 hours after starting antibiotic treatment or until sores have completely crusted over and healed. Children should stay home from school or daycare during the contagious period. The bacteria spread through direct contact with sores or contaminated items like towels and clothing.
Factors That Affect Duration
- Prompt treatment: Starting antibiotics within the first few days leads to faster resolution
- Type of impetigo: Bullous and ecthyma forms take longer
- Immune status: Immunocompromised individuals may experience prolonged illness
- Hygiene practices: Regular cleaning and covering sores prevents reinfection and spread
- MRSA involvement: Methicillin-resistant strains may require alternative antibiotics and longer treatment
When to See a Doctor
Seek medical attention if sores are not improving after 3 days of antibiotic treatment, the rash is spreading rapidly, fever develops, or urine turns dark or red — which could indicate a rare kidney complication (post-streptococcal glomerulonephritis).