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URL of this page: https://medlineplus.gov/druginfo/meds/a682537.html

Doxylamine

pronounced as (dox il' a meen)

Why is this medication prescribed?

Doxylamine is used in the short-term treatment of insomnia (difficulty falling asleep or staying asleep). Doxylamine is also used in combination with decongestants and other medications to relieve sneezing, runny nose, and nasal congestion caused by the common cold. Doxylamine should not be used to cause sleepiness in children. Doxylamine is in a class of medications called antihistamines. It works by blocking the action of histamine, a substance in the body that causes allergic symptoms.

How should this medicine be used?

Doxylamine comes as a tablet to take by mouth for sleep, and in combination with other medications as a liquid and liquid-filled capsule to treat symptoms of the common cold. When doxylamine is used to reduce difficulty falling asleep, it usually is taken 30 minutes before bedtime. When doxylamine is used to treat cold symptoms, it is usually taken every 4 to 6 hours. Follow the directions on the package label or on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take doxylamine exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor or directed on the package label.

Doxylamine comes alone and in combination with pain relievers, fever reducers, and cough suppressants, If you are choosing a product to treat cough or cold symptoms, ask your doctor or pharmacist for advice on which product is best for your symptoms. Check nonprescription cough and cold product labels carefully before using two or more products at the same time. These products may contain the same active ingredient(s) and taking them together could cause you to receive an overdose.

Nonprescription cough and cold combination products, including products that contain doxylamine, can cause serious side effects or death in young children. Do not give nonprescription products that contain doxylamine to children younger than 4 years of age. Ask a doctor before giving these products to children 4 to 12 years of age.

Cough and cold symptoms that get worse or that do not go away may be signs of a more serious condition. If you are taking doxylamine in combination with other medications to treat cough and cold symptoms, call your doctor if your symptoms worsen or if they last longer than 7 days.

If you are taking doxylamine to treat insomnia, you will probably become very sleepy soon after you take the medication and will remain sleepy for some time after you take the medication. Plan to remain asleep for 7 to 8 hours after taking the medication. If you get up too soon after taking doxylamine, you may be drowsy.

Doxylamine should only be used to treat insomnia for a short time. Call your doctor if you feel that you need to take doxylamine for longer than 2 weeks.

If you are using the liquid, do not use a household spoon to measure your dose. Use the measuring cup or spoon that came with the medication or use a spoon that is made especially for measuring medication.

Other uses for this medicine

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

What special precautions should I follow?

Before taking doxylamine,

  • tell your doctor and pharmacist if you are allergic to doxylamine, any other medications, or any of the ingredients in the doxylamine preparation. Ask your doctor or pharmacist or check the package label for a list of the ingredients.
  • tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: medications for colds, hay fever, or allergies; medications for depression; muscle relaxants; narcotic medications for pain; sedatives; sleep medications; and tranquilizers.
  • tell your doctor if you have or have ever had asthma, emphysema, chronic bronchitis, or other breathing problems; glaucoma (a condition in which increased pressure in the eye can lead to gradual loss of vision); ulcers; difficulty urinating (due to an enlarged prostate gland); heart disease, high blood pressure, seizures,or an overactive thyroid gland.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking doxylamine, call your doctor.
  • if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking doxylamine.
  • you should know that this medication may make you drowsy. Do not drive a car or operate machinery until you know how this medication affects you.
  • remember that alcohol can add to the drowsiness caused by this medication. Avoid alcoholic beverages while you are taking this medication.
  • talk to your doctor about the risks and benefits of taking doxylamine if you are 65 years of age or older. Older adults should not usually take doxylamine because it is not as safe or effective as other medications that can be used to treat the same condition.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget a dose?

Doxylamine is usually taken as needed. If your doctor has told you to take doxylamine regularly, take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

What side effects can this medication cause?

Doxylamine may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • dry mouth, nose, and throat
  • drowsiness
  • nausea
  • increased chest congestion
  • headache
  • excitement
  • nervousness

Some side effects can be serious. If you experience any of the following symptoms, call your doctor immediately:

  • vision problems
  • difficulty urinating

Doxylamine may cause other side effects. Call your doctor if you have any unusual problems while you are taking this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What other information should I know?

Ask your pharmacist any questions you have about doxylamine.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Aldex AN®
  • Nighttime Sleep Aid
  • Unisom® SleepTabs

Brand names of combination products

  • Alka-Seltzer Plus® Night Cold Formula (containing Aspirin, Dextromethorphan, Doxylamine, Phenylephrine)
  • Coricidin® HBP Nighttime Multi-Symptom Cold (containing Acetaminophen, Dextromethorphan, Doxylamine)
  • Tylenol® Cold and Cough Nighttime (containing Acetaminophen, Dextromethorphan, Doxylamine)
  • Vicks NyQuil® Cold and Flu Relief (containing Acetaminophen, Dextromethorphan, Doxylamine)
  • Vicks NyQuil® Cold and Flu Symptom Relief Plus Vitamin C (containing Acetaminophen, Dextromethorphan, Doxylamine)
  • Vicks NyQuil® Cough (containing Dextromethorphan, Doxylamine)
  • Vicks NyQuil® Sinex Nighttime Sinus Relief (containing Acetaminophen, Doxylamine, Phenylephrine)
  • Zicam® Multi-Symptom Cold and Flu Nighttime (containing Acetaminophen, Dextromethorphan, Doxylamine)
Last Revised - 07/15/2018