Doxepin (Insomnia)
Brand Name(s): Silenor®; also available generically
WHY is this medicine prescribed?
Doxepin (Silenor) is used to treat insomnia (difficulty falling asleep or staying asleep) in people who have trouble staying asleep. Doxepin (Silenor) is in a class of medications called tricyclic antidepressants. It works by slowing activity in the brain to allow sleep.
Doxepin is also available as a capsule and liquid to treat depression and anxiety. This monograph only gives information about doxepin (Silenor) for insomnia. If you are using this medication for depression or anxiety, read the monograph entitled doxepin (depression, anxiety).
HOW should this medicine be used?
Doxepin (Silenor) comes as a tablet to take by mouth. It is usually taken once a day, within 30 minutes of bedtime. Do not take doxepin (Silenor) within 3 hours of a meal. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take doxepin (Silenor) exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.
You will probably become very sleepy soon after you take doxepin (Silenor) and will remain sleepy for some time after you take the medication. Plan to go to bed right after you take doxepin (Silenor) and to stay in bed for 7 to 8 hours. Do not take doxepin (Silenor) if you will be unable to go to bed right away and remain asleep for 7 to 8 hours after taking the medication.
You should begin to sleep better during the first few days of treatment with doxepin (Silenor). If your sleep does not improve within 7-10 days, or gets worse call your doctor.
Your doctor or pharmacist will give you the manufacturer's patient information sheet (Medication Guide) when you begin treatment with doxepin (Silenor) and each time you refill your prescription. Read the information carefully and ask your doctor or pharmacist if you have any questions. You can also visit the Food and Drug Administration (FDA) website (https://www.fda.gov/Drugs/DrugSafety/ucm085729.htm) to obtain the Medication Guide.
Are there OTHER USES for this medicine?
This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.
What SPECIAL PRECAUTIONS should I follow?
Before taking doxepin (Silenor),
- tell your doctor and pharmacist if you are allergic to doxepin (Silenor), amoxapine, loxapine, any other medications, or any of the ingredients in doxepin (Silenor) tablets. Ask your pharmacist or check the Medication Guide for a list of the ingredients.
- tell your doctor if you are taking a monoamine oxidase (MAO) inhibitor such as isocarboxazid (Marplan), phenelzine (Nardil), selegiline (Eldepryl, Emsam, Zelapar), and tranylcypromine (Parnate), or if you have stopped taking an MAO inhibitor within the past 14 days. Also tell your doctor if you are taking or receiving methylene blue (Provayblue) or linezolid (Zyvox). Your doctor will probably tell you not to take doxepin. If you stop taking doxepin, you should wait at least 14 days before you start to take an MAO inhibitor.
- tell your doctor and pharmacist what other 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: cimetidine (Tagamet); medications for cough, cold, or allergies; quinidine (in Nuedexta); sedatives; selective serotonin reuptake inhibitors (SSRIs) such as citalopram (Celexa), escitalopram (Lexapro), fluoxetine (Prozac, Sarafem, Selfemra, in Symbyax), fluvoxamine (Luvox), paroxetine (Brisdelle, Paxil, Pexeva), and sertraline (Zoloft); other sleeping pills; tolazamide; and tranquilizers. Your doctor may need to change the doses of your medications or monitor you carefully for side effects. Many other medications may also interact with doxepin (Silenor), so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list.
- tell your doctor if you have or have ever had glaucoma that is not being treated, or urinary retention (inability to empty your bladder completely or at all). Your doctor may tell you not to take doxepin (Silenor).
- tell your doctor if you have or have ever drunk large amounts of alcohol, used street drugs, or over-used prescription medications. Also tell your doctor if you have or have ever had depression, mental illness, suicidal thoughts, sleep apnea (a sleep disorder that causes breathing to stop for short periods during sleep), or kidney or liver disease.
- tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking doxepin (Silenor), call your doctor.
- you should know that doxepin (Silenor) may make you drowsy. Do not drive a car, operate machinery, or do other dangerous activities at night after taking doxepin (Silenor). Do not drive a car or operate machinery the next day until you know how this medication affects you.
- you should know that alcohol can add to the drowsiness caused by this medication. Do not drink alcohol while you are taking doxepin (Silenor).
- you should know that some people who took doxepin (Silenor) got out of bed and drove their cars, prepared and ate food, had sex, made phone calls, were sleep-walking, or were involved in other activities while not fully awake. After they woke up, these people were usually unable to remember what they had done. Call your doctor right away if you find out that you have been driving or doing anything else unusual while you were sleeping.
What SPECIAL DIETARY instructions should I follow?
Unless your doctor tells you otherwise, continue your normal diet.
What should I do IF I FORGET to take a dose?
Doxepin (Silenor) should only be taken at bedtime. If you did not take doxepin (Silenor) before you went to bed and you are having trouble sleeping, you may take doxepin (Silenor) if you will be able to stay in bed for at least 7 to 8 hours afterward. Do not take a double dose of doxepin (Silenor) to make up for a missed dose.
What SIDE EFFECTS can this medicine cause?
Doxepin (Silenor) may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:
Doxepin (Silenor) may cause other side effects. Call your doctor if you have any unusual problems while 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 (https://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 light, and excess heat and moisture (not in the bathroom).
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 (https://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.
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. https://www.upandaway.org
What should I do in case of 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.
Symptoms of overdose may include:
- irregular heart beat
- feeling agitated, confused, or drowsy
- trouble concentrating
- seizures
- muscle stiffness
- vomiting
- increase in pupil size
- hallucination (seeing things or hearing voices that do not exist)
- fever
- cold body temperature
- coma (loss of consciousness for a period of time)
What OTHER INFORMATION should I know?
Keep all appointments with your doctor.
Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.
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.
This report on medications is for your information only, and is not considered individual patient advice. Because of the changing nature of drug information, please consult your physician or pharmacist about specific clinical use.
The American Society of Health-System Pharmacists, Inc. represents that the information provided hereunder was formulated with a reasonable standard of care, and in conformity with professional standards in the field. The American Society of Health-System Pharmacists, Inc. makes no representations or warranties, express or implied, including, but not limited to, any implied warranty of merchantability and/or fitness for a particular purpose, with respect to such information and specifically disclaims all such warranties. Users are advised that decisions regarding drug therapy are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and the information is provided for informational purposes only. The entire monograph for a drug should be reviewed for a thorough understanding of the drug's actions, uses and side effects. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information is not a substitute for medical care.
AHFS® Patient Medication Information™. © Copyright, 2024. The American Society of Health-System Pharmacists®, 4500 East-West Highway, Suite 900, Bethesda, Maryland. All Rights Reserved. Duplication for commercial use must be authorized by ASHP.
Selected Revisions: May 24, 2017.