Before hops was used in beer recipes, beer could make you hallucinate or even kill you. Read more here:

The earliest mention of beer in history was in the year 974. Today, hops is the main flavoring agent used in beer, but that wasn’t always the case. Before the 11th century, a compound called gruit was where beer got its flavoring. Gruit is made of several different plants, including Hyoscyamus Niger, commonly known as “Stinking Nightshade”.

When Stinking Nightshade is consumed by humans and most animals, it releases chemical to the brain as natural defense system. Side effects from ingesting the plant include hallucinations, dilated pupils, the sensation of flight, extreme energy, flushed skin, and in some cases death. This plant was also used in conjunction with other plants as a remedy for pain.

During the 11th to 16th centuries, beer recipes began to call for hops instead of gruit (along with Stinking Nightshade). Due to the deaths of Stinking Nightshade, a law was set in place. In 1516, The Bavarian Purity Law, also known as the German Purity Law went into effect. It stated, that beer was only allowed to be made using four ingredients: barley, hops, yeast and water. This is the common recipe still used today.

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