Lemon Balm

Description

 

Lemon Balm, also known as Melissa, is a relaxant sometimes used in flavouring ice cream and herbal teas^[1]. One product, Lemon Balm Extract - 2 oz. - Liquid from Gaia Herbs, has an incredible flavor reminiscent of a citrus like essence. Although, it doesn't only carry Lemon Balm it's most predominant flavor is sweet citrus and is enjoyable enough to drink without restraint (although it wouldn't be recommended due to its sedative nature and bell-like response curve - see Overdosing section). The manner by which this product works involves GABA, a neurotransmitter whose application is related to anxiety and epilepsy^[3][4]. It is also found to have strong antioxidant effects in the hippocampus. There is also discussion to its benefit in ADHD^[5], but it is possible that this would more along the lines alleviate hyperactivity due to its sedative nature.

Mechanism of Action

A novel pharmacological mechanism of action for the anxiolytic botanical  Melissa officinalis L. (lemon balm) is reported. The methanol extract  was identified as a potent in vitro inhibitor of rat brain GABA  transaminase (GABA-T), an enzyme target in the therapy of anxiety,  epilepsy and related neurological disorders. Bioassay-guided  fractionation led to the identification and isolation of rosmarinic acid  (RA) and the triterpenoids, ursolic acid (UA) and oleanolic acid (OA)  as active principles. Phytochemical characterization of the crude  extract determined RA as the major compound responsible for activity  (40% inhibition at 100 microg/mL) since it represented approximately  1.5% of the dry mass of the leaves. Synergistic effects may also play a  role. Copyright 2009 John Wiley & Sons, Ltd.^[3]

Possible Interactions

Lemon balm is generally  regarded as safe. However, it may potentially interact with the  following medications:


Sedatives, thyroid medications  -- Although there is no scientific evidence of this, lemon balm may  interact with sedatives and thyroid medications. If you are taking  sedatives (for insomnia or anxiety) or medications to regulate your  thyroid, ask your doctor before taking lemon balm.

Overdosing

The highest dose [1600 mg of encapsulated dried leaf], however, was not associated with any benefits, and led to the most pronounced decrements on the memory tasks along with reduced ‘alertness’ at all postdose testing sessions.^[6]

Research
Cognitive Enhancement

In another double-blind, placebo-controlled study, 18 healthy volunteers  received two separate single doses of a standardized lemon balm extract  (300 mg and 600 mg) or placebo for 7 days. The 600 mg dose of lemon  balm increased mood and significantly increased calmness and alertness.^[2]

Melissa officinalis (Lemon balm) is a herbal medicine that has  traditionally been attributed with memory-enhancing properties, but  which is currently more widely used as a mild sedative and sleep aid. In  a previous study it was demonstrated that a commercial Melissa extract  led to dose-specific increases in calmness, and dose-dependent  decrements in timed memory task performance. However, the extract  utilized in that study did not exhibit in vitro cholinergic  receptor-binding properties. The current study involved an initial  screening of samples of M. officinalis for human acetylcholinesterase  inhibition and cholinergic receptor-binding properties. The cognitive  and mood effects of single doses of the most cholinergically active  dried leaf were then assessed in a randomized, placebo-controlled,  double-blind, balanced crossover study. Following the in vitro analysis,  20 healthy, young participants received single doses of 600, 1000, and  1600 mg of encapsulated dried leaf, or a matching placebo, at 7-day  intervals. Cognitive performance and mood were assessed predose and at  1, 3, and 6 h postdose using the Cognitive Drug Research computerized  assessment battery and Bond–Lader visual analog scales, respectively. In  vitro analysis of the chosen extract established IC50 concentrations of  0.18 and 3.47 mg ml 1, respectively, for the displacement of  [3H]-(N)-nicotine and [3H]-(N)-scopolamine from nicotinic and muscarinic  receptors in human cerebral cortex tissue. However, no cholinesterase inhibitory properties were detected. The most notable  cognitive and mood effects were improved memory performance and  increased ‘calmness’ at all postdose time points for the highest (1600  mg) dose. However, while the profile of results was overwhelmingly  favorable for the highest dose, decrements in the speed of timed memory  task performance and on a rapid visual information-processing task  increased with decreasing dose. These results suggest that doses of  Melissa officinalis at or above the maximum employed here can improve  cognitive performance and mood and may therefore be a valuable adjunct  in the treatment of Alzheimer’s disease. The results also suggest that  different preparations derived from the same plant species may exhibit  different properties depending on the process used for the sample  preparation.^[6]

Alzheimer's Disease

Objective: To assess the efficacy and safety of Melissa officinalis extract using a fixed dose (60 drops/day) in patients with mild to moderate Alzheimer’s disease.

Design: A four month, parallel group, placebo controlled trial undertaken in three centres in Tehran, Iran.


Methods: Patients with mild to moderate Alzheimer’s disease aged between 65 and 80 years (n = 42; 18 women, 24 men) with a score of ≥ 12 on the cognitive subscale of Alzheimer’s disease assessment scale (ADAS-cog) and ≤ 2 on the clinical dementia rating (CDR) were randomised to placebo or fixed dose of Melissa officinalis extract. The main efficacy measures were the change in the ADAS-cog and CDR-SB scores compared with baseline. Side effects were systematically recorded.

Results: At four months, Melissa officinalis extract produced a significantly better outcome on cognitive function than placebo (ADAS-cog: df = 1, F = 6.93, p = 0.01; CDR: df = 1, F = 16.87, p < 0.0001). There were no significant differences in the two groups in terms of observed side effects except agitation, which was more common in the placebo group (p = 0.03).


Conclusions:Melissa officinalis extract is of value in the management of mild to moderate Alzheimer’s disease and has a positive effect on agitation in such patients.

Herpes

Some studies suggest that topical ointments containing lemon balm may  help heal cold sores caused by the herpes simplex virus (HSV). In one  study of 116 people with HSV, those who applied lemon balm cream to  their lip sores experienced significant improvement in redness and  swelling after only 2 days. Other symptoms, such as pain and scabbing,  did not improve. Both the patients and their doctors reported that the  lemon balm ointment was highly effective. Several animal studies also  support the value of topical lemon balm for herpes lesions.^[2]

References
^[1] Wikipedia: Lemon Balm
^[2] University of Maryland Medical Center - Lemon Balm
^[3] Bioassay-guided fractionation of lemon balm (Melissa officinalis L.) using an in vitro measure of GABA transaminase activity.
^[4] Wikipedia: GABA
^[5] WebMD: Lemon Balm
^[6] Modulation of Mood and Cognitive Performance Following Acute Administration of Single Doses of Melissa Officinalis (Lemon Balm) with Human CNS Nicotinic and Muscarinic Receptor-Binding Properties