Condition
Cold Sores
Cold sores are blisters on or around the lips, caused by herpes simplex virus type 1, which lingers in nerve cells after childhood infection and can flare with stress, sun, or illness. L-lysine, topical honey, and zinc have the strongest evidence among supplements, rated moderate, but the one lysine study found no clear difference in how often sores came back. That trial was tiny, just 26 people, so it says little either way.
Sources: PMID 26252373
- Supplements studied
- 3
- Graded outcomes
- 1
- Trials
- 1
- People studied
- 3,673
Evidence by supplement
- Strong
- Moderate
- Limited
- Very limited
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Cold Sore Recurrence Frequency No effect | NoneNo effect | 1 study | 26 people | |||
Studies that measured cold sore recurrence frequency | ||||||
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Cold Sore Symptom Severity | Improves (the measure goes down) | 1 study | 66 people | |||
Studies that measured cold sore symptom severity | ||||||
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Cold Sore Symptom Duration | Improves (the measure goes up) | 1 study | 839 people | |||
Studies that measured cold sore symptom duration | ||||||
Key findings
- Cold Sore Recurrence Frequency
The Cold Sores (Herpes Labialis) Prevention and Treatment protocol
2 primary supplements · 6 supporting supplements
- L-Lysine1,000 mg 3 times daily during outbreak; 500–1,000 mg daily for prevention
- Honey (Topical)Apply medical-grade honey (Manuka or similar) to lesion 3–4 times daily
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Studies cited
1 study from PubMed