Diphen

Generic Name: diphenhydramine (DYE fen HYE dra meen)
Brand Name: Aler-Dryl, Allergy, Allergy Relief (Diphenhydramine HCl), Allermax, Altaryl, Banophen, Benadryl, Calm-Aid, Compoz Nighttime Sleep Aid, Diphedryl, Diphen, Diphenhist, Dytuss, Genahist, Hydramine, Nytol QuickCaps, PediaCare Children's Allergy, Scot-Tussin Allergy Relief Formula, Siladryl, Silphen Cough, Simply Sleep, Sleep-ettes, Sleepinal, Sominex, Theraflu Thin Strips Multi Symptom, Tranquil, Triaminic Thin Strips Allergy, Twilite, Unisom Sleepgels Maximum Strength, Unisom SleepMelts, ZzzQuil

What is Diphen (diphenhydramine)?

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

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

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

Diphenhydramine may also be used for purposes not listed in this medication guide.

What is the most important information I should know about Diphen (diphenhydramine)?

Do not use diphenhydramine if you have taken an MAO inhibitor in the past 14 days. A dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, phenelzine, rasagiline, selegiline, and tranylcypromine.

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What should I discuss with my healthcare provider before taking Diphen (diphenhydramine)?

Do not use diphenhydramine if you have taken an MAO inhibitor in the past 14 days. A dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, phenelzine, rasagiline, selegiline, and tranylcypromine.

Ask a doctor or pharmacist if it is safe for you to take this medicine if you have other medical conditions, especially:

• a blockage in your stomach or intestines;

• urination problems;

• a stomach ulcer;

• heart disease, high blood pressure;

• asthma or COPD;

• glaucoma;

• a thyroid disorder; or

• an enlarged prostate, bladder problems or if you are unable to urinate.

• hypertension or any type of heart problems; or

• asthma.

FDA pregnancy category B. Diphenhydramine is not expected to harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment.

Diphenhydramine can pass into breast milk and may harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

Diphenhydramine may pass into breast milk and may harm a nursing baby. Antihistamines may also slow breast milk production. Do not use this medicine without medical advice if you are breast-feeding a baby.

Older adults may be more likely to have side effects from this medicine.

How should I take Diphen (diphenhydramine)?

Use exactly as directed on the label, or as prescribed by your doctor. Do not use in larger or smaller amounts or for longer than recommended.

Take each dose with a full glass of water.

Measure liquid medicine with a special dose-measuring spoon or medicine cup. If you do not have a dose-measuring device, ask your pharmacist for one.

Diphenhydramine 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, diphenhydramine should be taken approximately 30 minutes before bedtime.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking Diphen (diphenhydramine)?

This medication may cause blurred vision and may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert and able to see clearly.

Drinking alcohol can increase certain side effects of diphenhydramine.

Diphen (diphenhydramine) side effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Stop using diphenhydramine and call your doctor at once if you have:

• fast or uneven heart rate;

• mood changes;

• tremor, seizure (convulsions);

• easy bruising or bleeding, unusual weakness;

• shortness of breath; or

• little or no urinating.

Common side effects may include:

• dizziness, drowsiness;

• dry mouth, nose, or throat;

• constipation;

• blurred vision; or

• feeling nervous or restless.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Diphen side effects (in more detail)

What other drugs will affect Diphen (diphenhydramine)?

Taking diphenhydramine with other drugs that make you sleepy or slow your breathing can increase these effects. Ask your doctor before taking diphenhydramine with a sleeping pill, narcotic pain medicine, muscle relaxer, or medicine for anxiety, depression, or seizures.

Ask a doctor or pharmacist if it is safe for you to use diphenhydramine if you are also using any of the following drugs:

• bladder or urinary medicines such as darifenacin, fesoterodine, oxybutynin, tolterodine, solifenacin;

• bronchodilators such as ipratropium or tiotropium;

• cold or allergy medicine that contains an antihistamine;

• medication for Parkinson's disease; or

• medication to treat excess stomach acid, stomach ulcer, motion sickness, or irritable bowel syndrome.

This list is not complete. Other drugs may interact with diphenhydramine, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

Where can I get more information?

• Your pharmacist can provide more information about diphenhydramine.