The aim of this article is to discuss chloral hydrate and its place in current therapy in various paediatric settings following the 2021 safety update from the Medicines and Healthcare products Regulatory Agency (MHRA). There are two case studies presented to apply learning relating to the place of chloral hydrate in both paediatric sedation and neurology.

When the MHRA issued a drug safety update in October 2021 relating to the use of chloral hydrate and its prodrug cloral betaine in paediatric patients, it sparked concern for families and the paediatric medical community.1 While no new safety concerns were identified, previously known carcinogenicity data in animals, and lack of long-term studies in humans (particularly in infants and neonates), led to the MHRA issuing new prescribing restrictions and advice for healthcare professionals and parents/carers.

MHRA advice to prescribers can be summarised as follows:

Use in children and adolescents is not routinely recommended, and should be under the supervision of a specialist

Indicated in severe insomnia for those with a suspected or definite neurodevelopmental disorder where other treatments have failed

Short-term use only (maximum of 2 weeks) with repeated courses not recommended (only if it has undergone specialist reassessment)

Following prolonged treatment of 2 weeks or more, slowly taper the dose down before discontinuing to avoid withdrawal symptoms, including delirium

Chloral hydrate is one of the oldest known synthetic agents and has been used as a hypnotic and sedative agent since the 1800s. It is metabolised to an active metabolite, trichloroethanol, which is responsible for its pharmacological effects.2 The proposed mechanisms for depression of the central nervous system include potentiating γ- Aminobutyric acid type A (GABA-A) receptors, inhibition of excitatory amino acid-activated currents mediated by N-methyl-D-aspartate, and allosteric modulation of the 5- hydroxytryptamine three receptor-mediated depolarisation of the vagus nerve.3 …