Dichloralphenazone is a 1:2 mixture of antipyrine with chloral hydrate

Chloral hydrate

Chloral hydrate is a sedative and hypnotic drug as well as a chemical reagent and precursor. The name chloral hydrate indicates that it is formed from chloral by the addition of one molecule of water. Its chemical formula is C2H3Cl3O2....

. In combination with paracetamol

Paracetamol

Paracetamol INN , or acetaminophen USAN , is a widely used over-the-counter analgesic and antipyretic . It is commonly used for the relief of headaches and other minor aches and pains and is a major ingredient in numerous cold and flu remedies...

 and isometheptene

Isometheptene

Isometheptene is a sympathomimetic amine sometimes used in the treatment of migraines and tension headaches due to its vasoconstricting properties, that is, it causes constriction of blood vessels...

, it is the active ingredient of medications for migraine and vascular (tension) headaches, including Epidrin and Midrin. Performance impairments are common with this drug and caution is advised, for example when driving motor vehicles. Additional uses of dichloralphenazone include sedation for the treatment of short-term insomnia

Insomnia

Insomnia is most often defined by an individual's report of sleeping difficulties. While the term is sometimes used in sleep literature to describe a disorder demonstrated by polysomnographic evidence of disturbed sleep, insomnia is often defined as a positive response to either of two questions:...

, although there are probably better drug choices for the treatment of insomnia.