This drug may make you dizzy or drowsy or cause blurred vision. Do not drive, use machinery, or do any activity that requires alertness or clear vision until you are sure you can perform such activities safely. Avoid alcoholic beverages.
The dosage is based on your age, medical condition, and response to treatment. There are many brands and forms of diphenhydramine available. Read the dosing instructions carefully for each product because the amount of diphenhydramine may be different between products. Do not increase your dose or take this medication more often than directed.
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.
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.Information last revised November 2016. 2016 First Databank, Inc.
If your doctor has directed you to use this medication, remember that he or she 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.
l your doctor if your condition does not improve or if it worsens.
Take the tablet, capsule, or liquid form by mouth with or without food. Measure liquid forms of this medication using a special measuring device/spoon. Do not use a household spoon because you may not get the correct dose. If you have a single-dose form of this medication (such as a single-use whistle), you do not need to measure the dose.
GENERIC NAME(S): Diphenhydramine Hcl.
The rapidly-dissolving tablet or strip should be allowed to dissolve on the tongue and then swallowed, with or without water. The chewable tablets should be chewed thoroughly before being swallowed.
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.
l your doctor right away if you have any serious side effects, including: mental/mood changes (such as restlessness, confusion), difficulty urinating, fast/ irregular heartbeat.
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Liquid products, chewable tablets, or dissolving tablets/strips may contain sugar and/or aspartame. Liquid products may also contain alcohol. Caution is advised if you have diabetes, liver disease, phenylketonuria (PKU), or any other condition that requires you to limit/avoid these substances in your diet. Ask your doctor or pharmacist about using this product safely.
If you miss a dose, take it as soon as you remember. If it is near the time of your next dose, skip themissed dose and resume your usual dosing schedule. Do not double the dose to catch up.
This medication may interfere with certain laboratory tests (including allergy skin test), possibly causing false test results. Make sure laboratory personnel and all your doctors know you use this drug.
Get medical help right away if you have any very serious side effects, including: seizures.
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 (including 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.
To relieve dry mouth, suck (sugarless) hard candy or ice chips, chew (sugarless) gum, drink water, or use a saliva substitute.
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.
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Older adults may be more sensitive to the side effects of this drug, especially drowsiness, dizziness, confusion, constipation, or trouble urinating. Drowsiness, dizziness, and confusion can increase the risk of falling.
This drug passes into breast milk and may have undesirable effects on a nursing infant. Consult your doctor before breast -feeding.
To prevent motion sickness, take your dose 30 minutes before starting activity such as travel. To help you sleep, take your dose about 30 minutes before bedtime. If you continue to have difficulty sleeping for longer than 2 weeks, contact your doctor.
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Children may be more sensitive to the side effects of this drug. This drug can often cause excitement in young children instead of drowsiness.
Diphenhydramine is an antihistamine used to relieve symptoms of allergy, hay fever, and the common cold. These symptoms include rash, itching, watery eyes, itchy eyes /nose/throat, cough, runny nose, and sneezing. It is also used to prevent and treat nausea, vomiting and dizziness caused by motion sickness. Diphenhydramine can also be used to help you relax and fall asleep.
Keep all regular medical and laboratory appointments.
Before using this medication, l your doctor or pharmacist your medical history, especially of: breathing problems (such as asthma, emphysema ), high pressure in the eye ( glaucoma ), heart problems, high blood pressure, liver disease, seizures, stomach /intestine problems (such as ulcers, blockage), overactive thyroid ( hyperthyroidism ), difficulty urinating (for example, due to enlarged prostate ).
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This medication works by blocking a certain natural substance ( histamine ) that your body makes during an allergic reaction. Its drying effects on such symptoms as watery eyes and runny nose are caused by blocking another natural substance made by your body (acetylcholine).
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Store at room temperature away from moisture and light. Do not store in the bathroom. Do not freeze liquid forms of this medication. Keep all medications away from children and pets.
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Cough -and-cold products have not been shown to be safe or effective in children younger than 6 years. Therefore, do not use this product to treat cold symptoms in children younger than 6 years unless specifically directed by the doctor. Some products (such as long-acting tablets/capsules) are not recommended for use in children younger than 12 years. Ask your doctor or pharmacist for more details about using your product safely.
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. Canada residents can call a provincial poison control center. Symptoms of overdose may include: severe drowsiness, seizures, widened pupils. In children, mental/mood changes (such as restlessness, irritability, hallucinations ) may occur before drowsiness.
Some products that may interact with this drug include: antihistamines applied to the skin (such as diphenhydramine cream, ointment, spray).
Before having surgery, l your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).
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Follow all directions on the product package. If your doctor has prescribed this medication, take it as directed. If you are uncertain about any of the information, consult your doctor or pharmacist.
These products do not cure or shorten the length of the common cold and may cause serious side effects. To decrease the risk for serious side effects, carefully follow all dosage directions. Do not use this product to make a child sleepy. Do not give other cough -and-cold medication that might contain the same or similar ingredients (see also Drug Interactions section). Ask the doctor or pharmacist about other ways to relieve cough and cold symptoms (such as drinking enough fluids, using a humidifier or saline nose drops/spray).
CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.
Drowsiness, dizziness, constipation, stomach upset, blurred vision, or dry mouth /nose/throat may occur. If any of these effects persist or worsen, l your doctor or pharmacist promptly.
During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.
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l your doctor or pharmacist if you are taking other products that cause drowsiness such as opioid pain or cough relievers (such as codeine, hydrocodone ), alcohol, drugs for sleep or anxiety (such as alprazolam, lorazepam, zolpidem), muscle relaxants (such as carisoprodol, cyclobenzaprine ), or other antihistamines (such as cetirizine, chlorpheniramine ).
COMMON BRAND NAME(S): Benadryl, Genahist, Naramin, Sominex, Unisom.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at.
In the US.
WebMD does not provide medical advice, diagnosis or treatment. See additional information.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
Before taking diphenhydramine, l your doctor or pharmacist if you are allergic to it; or to dimenhydrinate ; 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.Diphenhydramine