Melissa officinalis (leaf extract)

Lemon balm is part of combined herbal products (Iberogast and analogues) with a confirmed effect in functional dyspepsia – post-prandial fullness, early satiety and epigastric pain per Rome IV criteria. Lemon balm essential oils relax intestinal smooth muscle and ease spasm. EMA HMPC separately recognises lemon balm for mild GI cramps. In monotherapy lemon balm has scarce data – clinical benefit is mainly proven for combined formulations. Taking 1–2 g of dried herb or an equivalent extract 2–3 times daily for 2–4 weeks is acceptable for mild symptoms. If symptoms persist beyond a month or come with weight loss, vomiting or blood in stool, gastroscopy is needed, not herbs.

Lemon balm is used for mild sleep disturbance and nervous tension – often combined with valerian. EMA HMPC in 2013 confirmed traditional-use status for these indications based on 30 years of practice. Several small RCTs with the proprietary Cyracos extract (Naturex) showed modest improvement in subjective sleep quality and lower anxiety, but samples were small and trials manufacturer-funded. No positive systematic review exists. The AASM 2021 insomnia guideline does not mention lemon balm. For mild episodic insomnia a short course of 300–600 mg of extract in the evening is acceptable. If the herb was prescribed as monotherapy for severe chronic insomnia, consider seeking a second opinion; the evidence for first-line CBT-I is far stronger.