Diphenhydramine (Systemic

This information from Lexicomp® explains what you need to know about this medication, including what it’s used for, how to take it, its side effects, and when to call your healthcare provider.

Brand Names: US

Aler-Dryl [OTC] [DSC]; Allergy Childrens [OTC]; Allergy Relief Childrens [OTC]; Allergy Relief [OTC]; Anti-Hist Allergy [OTC]; Aurodryl Allergy Childrens [OTC] [DSC]; Banophen [OTC]; Benadryl Allergy Childrens [OTC]; Benadryl Allergy Extra Str [OTC]; Benadryl Allergy Ultratabs [OTC]; Benadryl Allergy [OTC]; Complete Allergy Relief [OTC]; Di-Phen [DSC]; Diphen [DSC]; Diphen [OTC]; Diphenhist [OTC] [DSC]; FT Allergy Relief Childrens [OTC]; FT Allergy Relief [OTC]; FT Nighttime Sleep Aid [OTC]; FT Sleep-Aid Maximum Strength [OTC]; Geri-Dryl [OTC]; GoodSense Allergy Relief [OTC]; GoodSense Sleep Aid [OTC]; GoodSense Sleep-Aid Max Str [OTC]; M-Dryl [OTC]; MAXAllergy Kids [OTC]; Naramin [OTC]; Nighttime Sleep Aid [OTC]; Nytol Maximum Strength [OTC] [DSC]; Nytol [OTC] [DSC]; Ormir [OTC] [DSC]; PediaCare Childrens Allergy [OTC]; PediaClear Cough Childrens [OTC] [DSC]; Pharbedryl [OTC]; Siladryl Allergy [OTC]; Simply Sleep [OTC]; Sleep Tabs [OTC]; Total Allergy Medicine [OTC]; Total Allergy [OTC]; Vanamine PD [OTC] [DSC]; ZzzQuil [OTC]

Brand Names: Canada

Diphenist

What is this drug used for?

  • It is used to ease allergy signs.
  • It is used to help motion sickness.
  • It is used to treat sleep problems.
  • It is used to relieve coughing.
  • It is used to treat signs like Parkinson’s disease caused by other health problems.

What do I need to tell the doctor BEFORE my child takes this drug?

  • If your child is allergic to this drug; any part of this drug; or any other drugs, foods, or substances. Tell the doctor about the allergy and what signs your child had.
  • If your child is a premature baby or is a newborn. Do not give this drug to a premature baby or a newborn.

If your child is breast-feeding a baby:

  • Your child may need to avoid breast-feeding a baby.

This is not a list of all drugs or health problems that interact with this drug.

Tell the doctor and pharmacist about all of your child’s drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe to give this drug with all of your child’s other drugs and health problems. Do not start, stop, or change the dose of any drug your child takes without checking with the doctor.

What are some things I need to know or do while my child takes this drug?

All products:

  • Tell all of your child’s health care providers that your child is taking this drug. This includes your child’s doctors, nurses, pharmacists, and dentists.
  • Do not give your child more of this drug than what the doctor told you to give. Giving more of this drug than you are told may raise the chance of severe side effects.
  • Do not have your child use longer than you have been told by your child’s doctor.
  • Have your child avoid tasks or actions that call for alertness until you see how this drug affects your child. These are things like riding a bike, playing sports, or using items such as scissors, lawnmowers, electric scooters, toy cars, or motorized vehicles.
  • Alcohol may interact with this drug. Be sure your child does not drink alcohol.
  • Talk with your child’s doctor before your child uses marijuana, other forms of cannabis, or prescription or OTC drugs that may slow your child’s actions.
  • If the patient is a child, use this drug with care. The risk of feeling excitable may be higher in children.
  • Do not give your child other products that have diphenhydramine.

If your child is pregnant:

  • Tell the doctor if your child is pregnant or becomes pregnant. You will need to talk about the benefits and risks of your child using this drug while pregnant.

Products for sleep problems:

  • This drug is not for use in children younger than 12 years of age. However, the doctor may decide the benefits of taking this drug outweigh the risks. If your child has been given this drug, ask the doctor for information about the benefits and risks. Talk with the doctor if you have questions about giving this drug to your child.

All other products:

  • Different brands of this drug may be for use in different ages of children. Talk with the doctor before giving this drug to a child.
  • Do not use to make a child sleepy. Talk with the doctor.

What are some side effects that I need to call my child’s doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your child’s doctor or get medical help right away if your child has any of the following signs or symptoms that may be related to a very bad side effect:

  • Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Severe dizziness or passing out.
  • Change in balance.
  • Feeling less alert.

What are some other side effects of this drug?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your child’s doctor or get medical help if any of these side effects or any other side effects bother your child or do not go away:

  • Feeling dizzy or sleepy.
  • Thickening of mucus in nose or throat.
  • Feeling nervous and excitable.
  • Upset stomach or throwing up.

These are not all of the side effects that may occur. If you have questions about side effects, call your child’s doctor. Call your child’s doctor for medical advice about side effects.

You may report side effects to your national health agency.

How is this drug best given?

Give this drug as ordered by your child’s doctor. Read all information given to you. Follow all instructions closely.

All oral products:

  • Give this drug with or without food. Give with food if it causes an upset stomach.

Products for sleep problems:

  • Give at bedtime.

Chewable tablets and oral-disintegrating tablets:

  • Have your child chew or dissolve in the mouth. Do not let your child swallow it whole.
  • If your child has phenylketonuria (PKU), talk with your child’s doctor. Some products have phenylalanine.

Oral strip:

  • Have your child place oral strip on the tongue and let dissolve.

All liquid products:

  • Measure liquid doses carefully. Use the measuring device that comes with this drug. If there is none, ask the pharmacist for a device to measure this drug.
  • If your child has phenylketonuria (PKU), talk with your child’s doctor. Some products have phenylalanine.

Liquid (suspension):

  • Shake well before use.

Injection:

  • It is given as a shot into a muscle or vein.
  • This drug may cause tissue damage if it is given into the skin or into the fatty part under the skin. Talk with the doctor.

What do I do if my child misses a dose?

Products for sleep problems:

  • This drug is given on an as needed basis. Do not give to your child more often than told by the doctor.

All other oral products:

  • If your child takes this drug on a regular basis, give a missed dose as soon as you think about it.
  • If it is close to the time for your child’s next dose, skip the missed dose and go back to your child’s normal time.
  • Do not give 2 doses at the same time or extra doses.
  • Many times this drug is given on an as needed basis. Do not give to your child more often than told by the doctor.

Injection:

  • Call your child’s doctor to find out what to do.

How do I store and/or throw out this drug?

All oral products:

  • Store at room temperature protected from light. Store in a dry place. Do not store in a bathroom.

All liquid products:

  • Do not freeze.

Liquid (suspension):

  • Throw away any part not used after 8 weeks.

Injection:

  • If you need to store this drug at home, talk with your child’s doctor, nurse, or pharmacist about how to store it.

All products:

  • Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
  • Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.

General drug facts

  • If your child’s symptoms or health problems do not get better or if they become worse, call your child’s doctor.
  • Do not share your child’s drug with others and do not give anyone else’s drug to your child.
  • Some drugs may have another patient information leaflet. If you have any questions about this drug, please talk with your child’s doctor, nurse, pharmacist, or other health care provider.
  • If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Consumer Information Use and Disclaimer

This generalized information is a limited summary of diagnosis, treatment, and/or medication information. It is not meant to be comprehensive and should be used as a tool to help the user understand and/or assess potential diagnostic and treatment options. It does NOT include all information about conditions, treatments, medications, side effects, or risks that may apply to a specific patient. It is not intended to be medical advice or a substitute for the medical advice, diagnosis, or treatment of a health care provider based on the health care provider’s examination and assessment of a patient’s specific and unique circumstances. Patients must speak with a health care provider for complete information about their health, medical questions, and treatment options, including any risks or benefits regarding use of medications. This information does not endorse any treatments or medications as safe, effective, or approved for treating a specific patient. UpToDate, Inc. and its affiliates disclaim any warranty or liability relating to this information or the use thereof. The use of this information is governed by the Terms of Use, available at https://www.wolterskluwer.com/en/know/clinical-effectiveness-terms.

Last Reviewed Date

2023-12-22

Copyright

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Last Updated

Monday, December 12, 2022