Awaiting clinical review. This entry is sourced but has not yet been signed off by a pharmacist or clinician.

Melissa officinalis (leaf)

Lemon Balm

Lemon balm may ease mild anxiety and low mood, but the trials are small and disagree with one another, so the evidence is limited rather than proven. Side effects are rarely reported. The main caution is that the EU regulator says it may impair driving and advises against use in pregnancy, breastfeeding and children under 12.

Written by

Healthy and Herbal editorial team

Updated

29 September 2026

A lemon balm plant with bright green leaves

At a glance

Last reviewed 29 September 2026

Evidence

Limited

Best for

Mild anxiety

Typical form & use

Leaf extract or tea; 1% cold sore cream

Onset

About a week

Safety

May impair driving; avoid in pregnancy. 1 known interaction, most serious with thyroid medication.

Check with your medications →

What it's used for

Evidence is rated per use. The same ingredient can be strong for one thing and traditional for another.

Use	Evidence	What the research shows
Anxiety and low mood	Limited	A 2021 meta-analysis of randomised trials found lemon balm reduced anxiety scores more than placebo (standardised mean difference −0.98, 95% CI −1.63 to −0.33) and depression scores too (−0.47), with no serious side effects. The authors flag high heterogeneity, few trials and differing methods, and say the effect looks strongest in the acute setting. A single-dose study in 20 healthy adults found self-rated calmness rose at the lowest dose (300 mg), while the highest dose (900 mg) reduced alertness.^1,5
Cold sores (cream applied to skin)	Limited	In a trial of 66 people with recurrent cold sores, a 1% lemon balm extract cream applied four times daily for five days gave a lower combined symptom score on day 2 than placebo (4.03 versus 4.94). A 2025 systematic review of 7 herbal trials found lemon balm preparations consistently reduced pain and swelling, sometimes lesion size, and adverse events were minimal. The trials are small and varied in design; the review calls for larger studies.^2,3
Sleep quality	Limited	One double-blind crossover study of a phytosome (absorption-enhanced) lemon balm extract reported a 2.9-point lower Insomnia Severity Index score than placebo, and 87% versus 30% of people reporting better sleep. It is a single small study, the extract is a specific commercial formulation, and several authors are linked to the manufacturer. We found no systematic review of lemon balm alone for sleep.⁴
Mild digestive complaints (bloating, wind)	Traditional	The EU regulator recognises lemon balm leaf for mild gastrointestinal complaints including bloating and flatulence, on the basis of long-standing use alone. We found no clinical trial that we opened to test this.⁶

How much

Ranges below are what studies used and what supplements commonly contain. They are not a recommendation for you. Start at the low end.

EU monograph, tea

1.5–4.5 g leaf in 150 ml boiling water⁶

As an infusion, 1 to 3 times daily, for adults, the elderly and adolescents over 12.

EU monograph, extract

Liquid extract 2–4 ml; tincture 2–6 ml⁶

Each 1 to 3 times daily. Powdered leaf is 0.19–0.55 g, 2 to 3 times daily.

Single dose studied

300–900 mg standardised extract⁵

One acute study in healthy adults tested 300, 600 and 900 mg. Calmness rose at 300 mg; 900 mg lowered alertness. Trial extracts differ, so this is not a general dose.

Cold sore cream

1% extract, 4 times daily for 5 days³

The regimen in the single trial we read. Products on sale vary in strength.

Timing · The sources give no specific time of day. In the acute mood study, effects were assessed from 1 to 6 hours after a single dose. In the cold sore trial the cream was applied four times daily for five days.With food? · No source we read gave food guidance.How long to trial · The EU monograph advises seeing a doctor or qualified health professional if symptoms last longer than 2 weeks, or worsen.

How people take it

Herbal tea1.5–4.5 g leaf in 150 ml water, 1–3 times dailyThe traditional form in the EU monograph. Not the form tested in most trials.

Standardised extract (capsule)Follow the product labelThe form used in the clinical trials, but extracts and strengths differ between products and studies.

Tincture or liquid extract2–6 ml, 1–3 times daily (EU monograph)Contains ethanol, which the EU monograph says must be labelled.

Cream, applied to skin1% extract, 4 times daily for 5 days (trial)For recurrent cold sores. Not the same as the tea or capsule.

Safety

Who should avoid

Pregnancy and breastfeeding — safety not established, EU regulator advises against
Children under 12 — not recommended, too little data
Before driving or operating machinery — may impair ability
Known allergy to lemon balm or related plants

Known interactions

MonitorThyroid medication — Animal and lab studies suggest a water extract may inhibit thyroid stimulating hormone; the EU regulator says the clinical relevance is unknown.

Questions people ask

Does lemon balm work for anxiety?

It may help. A 2021 meta-analysis found lower anxiety scores than placebo, but with high heterogeneity and few trials, so the result should be treated cautiously. It is not a substitute for care if anxiety is affecting daily life.

Does lemon balm cream work for cold sores?

Small trials suggest it reduces pain and swelling and may shorten symptoms compared with placebo. The evidence base is small and the products differ, so it is best seen as a possible adjunct rather than a proven treatment.

Is lemon balm safe to take every day?

Side effects are rarely reported in the trials we read and the EU monograph lists none known. Long-term safety data were not found in the sources we read, and the EU regulator advises seeing a professional if symptoms last more than 2 weeks.

Is lemon balm safe in pregnancy?

It is not recommended. The EU regulator says safety in pregnancy and breastfeeding has not been established and there is not enough data to support use.

Sources

Last reviewed 29 September 2026 · Next review March 2027 · How we rate evidence