Herbs that Regulate Qi

Which herb "breaks up stagnant qi" to treat epigastric or abdominal distention? Because of its strong, downward nature, use caution during pregnancy.

Zhi Shi has a strong action which breaks the qi. It also unblocks plugs, whatever that means.

Source: Bensky, D. (2004). Chinese Herbal Medicine: Materia Medica. Seattle, WA: Eastland Press. pp. 517 [Q871]