ill-smelling European herb with rugose leaves and whorls of dark purple flowers

GoldBamboo

... Black horehound is different from white horehound, which is used to relieve colds and bloating.

Black horehound is believed to prevent or relieve spasms of the stomach which may also lessen nausea and vomiting. Because it also has mild sedative properties, black horehound has been used for treating "nervous" stomach associated with anxiety. Traditionally, it has been used to prevent and relieve motion sickness, although no evidence from human studies supports this use. Both its antinausea and anti-anxiety effects make black horehound useful for treating insomnia and general nervousness. In Europe, it is used commonly to relieve mild nervous conditions. ...

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?Black Horehound Scientific classification Kingdom: Plantae ...
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