First anti-comet medication

When Halley’s Comet passed through the inner Solar System in 1910 it was known that the Earth would pass through its tail. Spectroscopy had discovered the presence of cyanogen in the comet’s tail and this led to scaremongering that the toxic gas would destroy life on Earth. Panic buying of gas masks by the public followed as well as anti-comet umbrellas and anti-comet pills. In reality the gas in Halley’s tail was far too diffuse to affect Earth and those who took the anti-comet pills survived, along with everyone else.