What to do if I'm having dental work done and is being given noctec (chloral hydrate) since she is neele phobic. Any dangers?

Side effects. there is no drug without side effects. Noctec (chloral hydrate) is a sedative hypnotic can cause gastric and mucosal irritation. It will keep you comfortable during the dental procedure. If any concerns discussed with your sedation provider.
Informed consent. It is the responsibility of the health care practitioner actually treating you to discuss your treatment including any associated risks so that you fully understand it.