Chloral hydrate (By mouth)


Chloral Hydrate (KLOR-al HYE-drate)

Treats insomnia (trouble sleeping) and used to calm patients before or after surgery.

Brand Name(s)


There may be other brand names for this medicine.

When This Medicine Should Not Be Used

You should not use this medicine if you have ever had an allergic reaction to chloral hydrate. You should not use chloral hydrate if you have liver or kidney disease, severe heart disease, gastritis (inflammation of the stomach), or stomach ulcers.

How to Use This Medicine

Liquid Filled Capsule, Liquid

  • Your doctor will tell you how much medicine to take and how often.
  • Take this medicine exactly as your doctor ordered.
  • Do not chew or open the capsule. Swallow it whole with a full glass of water or fruit juice.
  • Mix the oral liquid with one-half glass of water, ginger ale, or fruit juice.

If a dose is missed:

  • Take your medicine as soon as you remember that you have missed your dose.
  • If it is nearly time for your next dose, wait until then to take the medicine and skip the missed dose.
  • You should not use two doses at one time.

How to Store and Dispose of This Medicine

  • Keep your medicine at room temperature in a tightly closed container, away from direct light. Do not freeze.
  • Keep all medicine out of the reach of children.

Drugs and Foods to Avoid

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

  • Avoid drinking alcohol or taking any medicine that could make you sleepy such as cold or allergy medicines, sleeping pills, other sedatives, muscle relaxants, tranquilizers, or narcotic pain killers while taking chloral hydrate.
  • Make sure your doctor knows if you are taking Coumadin®.

Warnings While Using This Medicine

  • If you are pregnant or breastfeeding, talk to your doctor before taking this medicine.
  • Check with your doctor before taking this medicine if you have severe heart disease.
  • This medicine may cause drowsiness. Be careful if you are driving or are using machinery.
  • This medicine may be habit-forming. You should not use more of this drug that your doctor ordered. Do not suddenly stop taking chloral hydrate without first asking your doctor.

Possible Side Effects While Using This Medicine

Call your doctor right away if you notice any of these side effects:

  • Hallucinations or confusion
  • Severe rash or hives
  • Trouble breathing

If you notice these less serious side effects, talk with your doctor:

  • Nausea, vomiting, stomach pain
  • Diarrhea
  • Dizziness or lightheadedness
  • Headache

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Version Info

  • Last Reviewed on 06/12/2013

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