As might be expected given its 2,000-year history of traditional use as a food, tea and medicine, lemon balm has an excellent safety track record. No serious negative effects have been associated with lemon balm to date.[1] The flip side of lemon balm’s calming, sedative effect, however, is that it may reduce alertness.[2][3][1]
Other things to be aware of:
- People with glaucoma should use care because of anecdotal reports that lemon balm may increase intraocular pressure.[2][1]
- People with thyroid conditions should use care because of the theoretical possibility of lemon balm affecting thyroid hormone levels.[4][5][6][7][8]
- People who take selective serotonin reuptake inhibitors (SSRIs) should be aware of the theoretical possibility that lemon balm could reduce their effectiveness.[3][1]