Vivien was also addicted to the sedative chloral hydrate. For example, barbiturates, ethanol, and chloral hydrate may precipitate this effect. It was considered to have superior sedative effects to both paraldehyde and chloral hydrate. Historically, chloral hydrate was utilized primarily as a psychiatric medication. In 1832 produced chloral hydrate, the first synthetic sleeping drug. Small amounts of chloral hydrate occur in some chlorinated water. The chloral hydrate is distilled from the reaction mixture. However, chloral hydrate was quite polar but nonetheless a potent hypnotic. Her death was attributed to an overdose of the chloral hydrate. Dichloralphenazone is a 1&colon;2 mixture of antipyrine with chloral hydrate. Deuterochloroform can be prepared by the reaction of sodium deuteroxide with chloral hydrate. This has led to chloral hydrate being replaced by alternative reagents in microscopy procedures. These diols are stable when strong electron withdrawing groups are present, as in chloral hydrate. Also chloral hydrate and guanethidine have been observed to increase BUN values. Its solution is used as an analytical reagent for chloral, aromatics, and vitamin A.