Cold sores
Supplements studied for cold sores.
Overview
Lysine has the strongest cold sore evidence here, with 10 indexed studies. Daily oral lysine around 1000–1248 mg, or 1000 mg three times daily, may reduce recurrence frequency and severity of herpes labialis, with longer six- to twelve-month regimens also studied.
Topical Zinc creams and zinc oxide–glycine formulations may shorten outbreaks and ease blistering, itching, and pain. Reishi has only been tested within a multi-herb mixture that shortened healing in one small trial, so isolated reishi effects remain unknown. See the heatmap and evidence reviews below.
Effect graph
Relevant supplements
Relevant supplements sorted by DEX Score.
Studies
Find individual evidence reviews for supplements sorted by DEX Score.
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LysineView supplement →
Consider purchase·★★★★★
How we scored this▸
- Research shows that taking lysine supplements (about 1000–1248 mg a day, or 1000 mg three times a day) can help reduce how often cold sores (herpes labialis) come back.
- Smaller studies also find that taking 1000 mg daily for up to a year, or 1000 mg three times a day for 6 months, may make cold sores less severe and shorten healing time.
Browse 10 studies
MetaInterventions for prevention of herpes simplex labialis (cold sores on the lips)2015n=295
A Cochrane review of 32 RCTs (2,640 participants) found oral aciclovir 400 mg twice daily modestly reduced herpes labialis recurrence (RR 0.26), while evidence for other preventive agents including lysine was limited or inconclusive.
- Effect
- No Benefit
- Duration
- 4 months
- Dose
- 400 mg 2×/day
- Participants
- 295
Open-labelSafety and effectiveness of an L-lysine, zinc, and herbal-based product on the treatment of facial and circumoral herpes2005n=30
An open-label study of a topical L-lysine, zinc, and herbal cream in facial/circumoral herpes found 87% of lesions fully resolved by day 6 vs typical 21-day course without treatment.
- Duration
- 3–6 days
- Population
- Adults
- Participants
- 30
Clinical effectiveness of lysine in treating recurrent aphthous ulcers and herpes labialis1994
A clinical report on oral lysine for recurrent aphthous ulcers and herpes labialis suggested symptomatic benefit, though the uncontrolled design limits firm conclusions.
- Effect
- Benefit
Controlled trialSuccess of L-lysine therapy in frequently recurrent herpes simplex infection. Treatment and prophylaxis1987n=27
A 6-month randomized trial in patients with frequently recurrent herpes simplex infection found that oral L-lysine (1 g three times daily) significantly reduced the number of recurrences, symptom severity, and healing time compared with placebo, supporting its use for both treatment and prophylaxis.
- Effect
- Benefit
- Duration
- 6 months
- Dose
- 1 g 3×/day
- Participants
- 27
RCTFailure of lysine in frequently recurrent herpes simplex infection. Treatment and prophylaxis1984n=21
A double-blind RCT of 21 patients with frequent herpes recurrences found 1,200 mg/day lysine did not significantly improve recurrence rate or severity vs placebo.
- Effect
- No Benefit
- Dose
- 200 mg/day
- Population
- Adults
- Participants
- 21
RCTLysine as a prophylactic agent in the treatment of recurrent herpes simplex labialis1984n=26
A 12-month double-blind crossover RCT of 26 patients with recurrent herpes labialis found 1,000 mg/day lysine significantly reduced lesion frequency when serum lysine exceeded 165 nmol/mL.
- Effect
- Benefit
- Dose
- 1000 mg/day
- Participants
- 26
RCTTreatment of recurrent herpes simplex infections with L-lysine monohydrochloride1984n=41
A double-blind crossover RCT of 41 patients found 1,248 mg/day L-lysine reduced herpes simplex recurrence rate and severity, while 624 mg/day was ineffective.
- Effect
- Benefit
- Dose
- 624 mg/day
- Population
- Adults
- Participants
- 41
Subjective response to lysine in the therapy of herpes simplex1983n=1,543
A survey of 1,543 patients taking ~936 mg/day lysine for 6 months reported 84% felt it prevented or reduced herpes recurrence frequency and 83% said lesions healed within 5 days.
- Duration
- 6 months
- Dose
- 936 mg/day
- Participants
- 1,543
Controlled trialLysine prophylaxis in recurrent herpes simplex labialis: a double-blind, controlled crossover study1980n=65
A double-blind crossover RCT of 65 patients found 1,000 mg/day lysine prophylaxis produced significantly more recurrence-free periods vs placebo (p=0.05), though overall recurrence rates did not differ.
- Effect
- No Benefit
- Duration
- 12 weeks
- Dose
- 1000 mg/day
- Population
- Adults
- Participants
- 65
A multicentered study of lysine therapy in Herpes simplex infection1978n=45
A multicenter study of 45 patients with recurrent herpes simplex given 312–1,200 mg/day lysine found accelerated recovery and reduced recurrence in a substantial proportion of participants.
- Effect
- Benefit
- Dose
- 200 mg/day
- Population
- Adults
- Participants
- 45
ZincView supplement →
Consider purchase·★★★★★
How we scored this▸
- Applying zinc creams or ointments can help shorten and lessen cold sore outbreaks.
- Zinc sulfate can ease symptoms for both mouth and genital herpes.
- A cream with 0.3% zinc oxide and glycine used every 2 hours may reduce blisters, itching, and pain, and shorten healing time from about 6.5 days to 5 days if started within 24 hours of the first symptoms.
- A product containing zinc oxide, L-lysine, and other ingredients can also help relieve symptoms.
- However, zinc treatments may not prevent frequent herpes recurrences.
Browse 5 studies
Open-labelSafety and effectiveness of an L-lysine, zinc, and herbal-based product on the treatment of facial and circumoral herpes2005n=30
An open-label study of a topical L-lysine, zinc, and herbal cream in facial/circumoral herpes found 87% of lesions fully resolved by day 6 vs typical 21-day course without treatment.
- Effect
- Benefit
- Duration
- 3–6 days
- Population
- Adults
- Participants
- 30
RCTA randomized clinical trial on the treatment of oral herpes with topical zinc oxide/glycine2001n=46
In 46 herpes patients starting zinc oxide/glycine cream within 24 hours of onset, mean lesion duration was 5.0 versus 6.5 days on placebo, with reduced blistering, soreness, itching, and tingling.
- Effect
- Benefit
- Duration
- 21 days
- Population
- Adults
- Participants
- 46
RCTLow concentration zinc sulphate solution in the management of recurrent herpes simplex infection1985
A clinical study evaluated low-concentration topical zinc sulphate solution for managing recurrent herpes simplex infection.
Clinical trialUse of topical zinc to prevent recurrent herpes simplex infection: review of literature and suggested protocols1985
A literature review reported that topical zinc preparations shorten duration and severity of orolabial and genital herpes outbreaks and that long-term use may greatly reduce genital herpes recurrences.
Clinical trialTopical treatment of recurrent herpes simplex and post-herpetic erythema multiforme with low concentrations of zinc sulphate solution1981
Clinical reports found low-concentration zinc sulphate solution (0.025–0.05% on skin, 0.01–0.025% on oral mucosa) prevented recurrent herpes simplex and post-herpetic erythema multiforme relapses.
- Effect
- Benefit
- Dose
- 0.025–0.05% zinc sulphate (skin); 0.01–0.025% (oral mucosa)
ReishiView supplement →
Reconsider purchase·★★★★★
How we scored this▸
- Reishi mushroom has only been studied as part of a mixture with other herbs for treating cold sores.
- In one small study, taking this herbal mix including reishi mushroom for about a week shortened cold sore healing time by almost 4 days compared to past outbreaks.
- There is no clear proof that reishi mushroom alone helps cold sores.
- More research is needed to understand if reishi by itself can treat or prevent cold sores effectively.
Browse 1 study
Clinical trialHerbal mixtures containing the mushroom Ganoderma lucidum improve recovery time in patients with herpes genitalis and labialis2007n=13
In 28 patients with recurrent herpes simplex, an herbal mix including Ganoderma lucidum shortened symptom resolution time compared with prior unsuccessful conventional treatment.
- Effect
- Benefit
- Population
- Patients with herpes genitalis and labialis
- Participants
- 13
- Avg age
- ~44–49
Evidence visualised
Same ratings as above, aggregated so you can see coverage and imbalance.