Evidence Level
Emerging
Magnolia bark has strong mechanistic evidence and growing clinical data. Alexeev et al. (2012) elucidated the mechanism, showing honokiol is a potent and selective positive allosteric modulator of GABA-A receptors. Talbott et al. (2013) provided the best clinical evidence with a 6-week RCT of Relora showing reduced cortisol and stress. Kuribara et al. (2000) demonstrated anxiolytic effects of honokiol in animal models comparable to diazepam without motor impairment. Qu et al. (2012) showed honokiol improved sleep in mice via GABA-A receptor modulation. The compound is notable for its efficient BBB penetration and multi-target pharmacology including anti-inflammatory and antioxidant effects.