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Benadryl

What is Benadryl

Benadryl is an antihistamine. Benadryl blocks the effects of the naturally occurring chemical histamine in your body.

Benadryl is used to treat sneezing; runny nose; itching, watery eyes; hives; rashes; itching; and other symptoms of allergies and the common cold.

Benadryl is also used to suppress coughs, to treat motion sickness, to induce sleep, and to treat mild forms of Parkinson's disease.

Benadryl may also be used for purposes other than those listed in this medication guide.

General medical information about Benadryl

Use caution when driving, operating machinery, or performing other hazardous activities. Benadryl may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities.

Use alcohol cautiously. Alcohol may increase drowsiness and dizziness while you are taking Benadryl.

Who should not take Benadryl

Do not take Benadryl if you have taken a monoamine oxidase inhibitor (MAOI) such as isocarboxazid (Marplan), phenelzine (Nardil), or tranylcypromine (Parnate) in the last 14 days. A very dangerous drug interaction could occur, leading to serious side effects.

Before taking this medication, tell your doctor if you have:
- glaucoma or increased pressure in the eye;
- a stomach ulcer;
- an enlarged prostate, bladder problems or difficulty urinating;
- an overactive thyroid (hyperthyroidism);
- hypertension or any type of heart problems; or
- asthma.

You may not be able to take Benadryl, or you may require a lower dose or special monitoring during treatment if you have any of the conditions listed above.

Benadryl is in the FDA pregnancy category B. This means that it is unlikely to harm an unborn baby. Do not take Benadryl without first talking to your doctor if you are pregnant.

Infants are especially sensitive to the effects of antihistamines, and serious side effects could occur in a breast-feeding baby. Benadryl is not recommended if you are breast-feeding. Do not take Benadryl without first talking to your doctor if you are nursing a baby.

If you are over 60 years of age, you may be more likely to experience side effects from Benadryl. You may require a lower dose of this medication.

How should take Benadryl

Take Benadryl exactly as directed on the package or as directed by your doctor. If you do not understand these directions, ask your pharmacist, nurse, or doctor to explain them to you.

Take each dose with a full glass of water.

Benadryl can be taken with or without food.

For motion sickness, a dose is usually taken 30 minutes before motion, then with meals and at bedtime for the duration of exposure.

As a sleep aid, Benadryl should be taken approximately 30 minutes before bedtime.

To ensure that you get a correct dose, measure the liquid forms of Benadryl with a special dose-measuring spoon or cup, not with a regular tablespoon. If you do not have a dose-measuring device, ask your pharmacist where you can get one.

Never take more of this medication than is prescribed for you. The maximum amount of Benadryl that you should take in any 24-hour period is 300 mg.

Store Benadryl at room temperature away from moisture and heat.

If you miss a dose:

Take the missed dose as soon as you remember. However, if it is almost time for your next dose, skip the missed dose and take only your next regularly scheduled dose. Do not take a double dose of this medication unless otherwise directed by your doctor.

What happens if you overdose:

Seek emergency medical attention.

Symptoms of a Benadryl overdose include extreme sleepiness, confusion, weakness, ringing in the ears, blurred vision, large pupils, dry mouth, flushing, fever, shaking, insomnia, hallucinations, and possibly seizures.

Avoid while taking Benadryl

Use caution when driving, operating machinery, or performing other hazardous activities. Benadryl may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities.

Use alcohol cautiously. Alcohol may increase drowsiness and dizziness while you are taking Benadryl.

Possible side effects of Benadryl

Stop taking Benadryl and seek emergency medical attention if you experience an allergic reaction (difficulty breathing; closing of your throat; swelling of your lips, tongue, or face; or hives).

Other, less serious side effects may be more likely to occur. Continue to take Benadryl and talk to your doctor if you experience
- sleepiness, fatigue, or dizziness;
- headache;
- dry mouth; or
- difficulty urinating or an enlarged prostate.

Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.

What other drugs will affect Benadryl

Do not take Benadryl if you have taken a monoamine oxidase inhibitor (MAOI) such as isocarboxazid (Marplan), phenelzine (Nardil), or tranylcypromine (Parnate) in the last 14 days. A very dangerous drug interaction could occur, leading to serious side effects.

Talk to your pharmacist before taking other over-the-counter cough, cold, allergy, or insomnia medications. These products may contain medicines similar to Benadryl, which could lead to an antihistamine overdose.

Before taking this medication, tell your doctor if you are taking any of the following medicines:
- anxiety or sleep medicines such as alprazolam (Xanax), diazepam (Valium), chlordiazepoxide (Librium), temazepam (Restoril), or triazolam (Halcion);
- medications for depression such as amitriptyline (Elavil), doxepin (Sinequan), nortriptyline (Pamelor), fluoxetine (Prozac), sertraline (Zoloft), or paroxetine (Paxil); or
- any other medications that make you feel drowsy, sleepy, or relaxed.

Drugs other than those listed here may also interact with Benadryl. Talk to your doctor and pharmacist before taking any prescription or over-the-counter medicines.

All prescription drugs:

A
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B
baclofen
bactrim bactroban baycol benadryl bextra biaxin boniva bontril buspar buspirone
C
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D
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E
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F
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G
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H
herceptin humalog humira hydroxyzine hyzaar  
I
ibuprofen imdur imitrex imodium inderal insulin integrilin iressa 
K
kaletra keflex kenalog keppra ketek klonopin kytril  
L
lamictal lamisil lanoxin lantus lasix lescol levaquin levitra levothyroxine levoxyl lexapro lidoderm lipitor lisinopril lithium lorazepam lortab lotensin lotrel lotrisone lovenox lupron luveris  
M
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N
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O
omeprazole omnicef orthovisc oxybutynin oxycodone oxycontin oxytrol  
P
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R
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S
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T
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U
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V
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W
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X
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Y
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Z
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