Lemon Balm Side Effects

By HerbaZest Editorial Team | Updated: Jun 18, 2020

Lemon Balm Side Effects

Although lemon balm has been safely used since ancient times - and it is still widely popular - there are some possible side effects and interactions to consider before consuming it.

Most Reported Side Effects of Lemon Balm

Unlike other sedative drugs, in adequate doses, lemon balm appears to be safe, and its sedating effects are not intensified by alcohol. However, some side effects have been reported:

  • Lemon balm may have a dependency risk

    It can lead to withdrawal symptoms when consumption is abruptly discontinued. According to a case study published in Medical Archives (2015), a university graduate who started an herbal treatment with Melissa officinalis and drank it regularly at night, without combining it with another plant-based tea, developed symptoms of dependency after increasing consumption from one cup every night to four cups daily, experiencing irritability and sleep disorders when not drinking it. He also experienced withdrawal after he stopped taking it and had to undergo a 10-day recovery.

    The study concluded that, although lemon balm tea side effects are extremely unusual and it is preferred by many people as an alternative to pharmaceutical drugs, there is a risk of dependency if it is taken in large doses for a long time.
  • Lemon balm can decrease alertness

    A double-blind study published in Psychosomatic Medicine (2004) reported that the consumption of 600 milligrams of M. officinalis under laboratory-induced psychological stress, along with significantly increased self-ratings of calmness, caused decreased alertness with and without drowsiness. On the other hand, a significant increase in the speed of mathematical processing, with no reduction in accuracy, was observed in participants who ingested just 300 milligrams.

    Although the results of the study suggest the potential of lemon balm to mitigate the effects of stress, they also highlight that the side effects of lemon balm are connected with higher-than-recommended dosage, especially when this herb is consumed during the day.

Unconfirmed Side Effects of Lemon Balm

  • Lemon balm may cause heart rate alterations

    Although no human studies have been conducted, a laboratory trial published in Research in Cardiovascular Medicine (2015) showed that elevated doses of M. officinalis may affect healthy cardiac functioning, slowing ventricular conductivity by blocking sodium, potassium, or both.

It's important to have in mind that all herbs affect the body in one way or another and the sensitivity to their medicinal actions may greatly vary from person to person.

Lemon Balm Cautions & Interactions

Lemon balm may cause undesirable effects under certain health conditions and interact with other herbs, supplements, or medications.

Lemon Balm Cautions

  • Heart conditions. Lemon balm can affect proper heart functioning. Until human studies are conducted and the results show no evidence of harm, people with cardiac conditions should avoid lemon balm consumption.

  • Hypotension. Since lemon balm can lower blood pressure, people with hypotension should not consume it.

  • Pregnancy. The safety of consumption of lemon balm during pregnancy and lactation has not been established. Although it has been traditionally used for morning sickness, due to the lack of scientific data to validate this practice it is recommendable to discontinue lemon balm's consumption during pregnancy and lactation.

Before taking any herbal supplement, people with preexisting conditions - e.g., chronic illnesses and genetic conditions - as well as those who are pregnant or breastfeeding should follow general precautions in accordance with medical advice.

Lemon Balm Interactions

Lemon balm may interact with sedatives and thyroid medications. This is why it is advised to avoid it when taking HIV medication, since it is not clear whether lemon balm interacts with antiretroviral agents.

According to the data collected, it can be concluded that the reported side effects of lemon balm are minimal compared with its medicinal value, therefore validating the safety of its consumption at appropriate doses.


  • Medical Archives, Does Melissa Officinalis Cause Withdrawal or Dependence?, 2015
  • Psychosomatic Medicine, Attenuation of laboratory-induced stress in humans after acute administration of Melissa officinalis (Lemon Balm), 2004
  • Research in Cardiovascular Medicine, Evaluation of Melissa officinalis (Lemon Balm) Effects on Heart Electrical System, 2015
  • University of Michigan Health, Lemon Balm
  • University of Maryland Medical Center, Lemon Balm