Several studies have found that lemon balm combined with other calming herbs (such as valerian, hops, and chamomile) helps reduce anxiety and promote sleep. In a recent 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.