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Chloral Hydrate - Oral

Pronunciation: KLOR-al HYE-drate

Common Brand Name(s): Noctec

Important: How To Use This Information

This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.

Uses

This medication is used to calm you just before surgery or other procedures. It belongs to a class of drugs known as hypnotics. It works by affecting certain parts of the brain to cause calmness.

How To Use

Take this medication by mouth with or without food as directed by your doctor, usually 30 minutes before your surgery/procedure. Follow your doctor's directions for how much liquid or food you can have before your procedure.

If you are using the liquid form of this medication, carefully measure the dose using a special measuring device/spoon. Do not use a household spoon because you may not get the correct dose. Mix your dose with a full glass of water or other liquid (such as fruit juice, ginger ale) before taking it.

Dosage is based on your medical condition and response to treatment. In children, the dosage is also based on weight.

Though it helps many people, this medication may sometimes cause addiction. This risk may be higher if you have a substance use disorder (such as overuse of or addiction to drugs/alcohol). Do not increase your dose, take it more often, or use it for a longer time than prescribed. Properly stop the medication when so directed.

If you suddenly stop using this medication, you may have withdrawal symptoms (such as sweating, trembling, anxiety, confusion, seizures, and hallucinations). Withdrawal from chloral hydrate can be severe (rarely fatal). To help prevent withdrawal, your doctor may lower your dose slowly. Withdrawal is more likely if you have used chloral hydrate for a long time or in high doses. Tell your doctor or pharmacist right away if you have withdrawal.

When this medication is used for a long time, it may not work as well. Talk with your doctor if this medication stops working well.

Side Effects

Drowsiness and trouble waking up in the morning, nausea, vomiting, stomach pain, diarrhea, and headache may occur. Stomach problems can be reduced by taking chloral hydrate with a full glass of water. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if you have any serious side effects, including:

  • mental/mood changes (such as confusion, thinking that others wish to harm you)
  • sleep-walking
  • staggering walk/loss of balance
  • severe dizziness
  • fainting

Long-term use may cause serious stomach problems (gastritis) or kidney problems. Tell your doctor right away if any of these serious side effects occur:

  • vomit that looks like coffee grounds
  • difficult/painful swallowing
  • black/tarry stools
  • severe stomach/abdominal pain
  • change in the amount of urine

Get medical help right away if you have any very serious side effects, including:

  • slow/shallow breathing

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:

  • rash
  • itching/swelling (especially of the face/tongue/throat)
  • severe dizziness
  • trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Precautions

Before taking chloral hydrate, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of:

  • personal or family history of a substance use disorder (such as overuse of or addiction to drugs/alcohol)
  • heart problems
  • kidney problems
  • liver problems
  • mental/mood conditions (such as depression, thoughts of suicide)
  • irritation of the swallowing tube (esophagus)
  • stomach problems (such as ulcer, gastritis)
  • a certain blood/liver disease (porphyria)
  • breathing problems (such as sleep apnea)

This drug may make you drowsy. Alcohol or marijuana (cannabis) can make you more drowsy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Avoid alcoholic beverages. Very severe side effects from use with alcohol may include inability to wake up and slowed breathing. Drinking alcohol may also result in severe stomach upset/cramps, nausea, vomiting, headache, or flushing. Talk to your doctor if you are using marijuana (cannabis).

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Older adults may be more sensitive to the side effects of this drug, especially drowsiness and confusion. These side effects can increase the risk of falling.

During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.

This drug passes into breast milk and may have undesirable effects on a nursing infant. Consult your doctor before breast-feeding.

Drug Interactions

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (such as prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Some products that may interact with this drug include:

  • "blood thinners" (such as warfarin)

The risk of serious side effects (such as slow/shallow breathing, severe drowsiness/dizziness) may be increased if this medication is taken with other products that may also cause drowsiness or breathing problems. Tell your doctor or pharmacist if you are taking other products such as opioid pain or cough relievers (such as codeine, hydrocodone), alcohol, marijuana (cannabis), other drugs for sleep or anxiety (such as alprazolam, lorazepam, zolpidem), muscle relaxants (such as carisoprodol, cyclobenzaprine), or antihistamines (such as cetirizine, diphenhydramine).

Check the labels on all your medicines (such as allergy or cough-and-cold products) because they may contain ingredients that cause drowsiness. Ask your pharmacist about using those products safely.

This medication may interfere with certain lab tests (such as certain urine tests for sugar, catecholamines, 17-hydroxycorticosteroids), possibly causing false test results. Make sure lab personnel and all your doctors know you use this drug.

Overdose

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Alberta residents can call PADIS (Poison and Drug Information Service) 24 hours a day at 1-800-332-1414. Canada residents can call a provincial poison control center. Symptoms of overdose may include: irregular heartbeat, fainting, inability to wake up, slowed breathing, bluish/cold skin.

Notes

Do not share this medication with others. Sharing it is against the law.

Missed Dose

Not applicable.

Storage

Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.

This information does not replace the advice of a doctor. Healthwise, Incorporated, disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. Learn how we develop our content.