Introduction

Diphenhydramine Hydrochloride (dye-fen-HYE-dra-meen hye-droe-KLOR-ide)

Treats severe allergic reactions, motion sickness, and symptoms of Parkinson's disease. This medicine is an antihistamine.

Brand Name(s)

There may be other brand names for this medicine.

Truxadryl, Benadryl, Banaril

When This Medicine Should Not Be Used

You should not use this medicine if you have had an allergic reaction to diphenhydramine, or if you are breast feeding a baby.

How to Use This Medicine

Injectable

• Your doctor will prescribe your exact dose and tell you how often it should be given. This medicine is given through a needle placed in one of your veins.It may also be given as a shot into one of your muscles.
• A nurse or other trained health professional will give you this medicine.

How to Store and Dispose of This Medicine

• If you store this medicine at home, keep it at room temperature, away from heat and direct light.Do not freeze.

Drugs and Foods to Avoid

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

• Tell your doctor if you are using any medicines that make you sleepy. These include sleeping pills, cold and allergy medicine, narcotic pain relievers, and sedatives.
• Tell your doctor if you are also using an MAO inhibitor (Eldepryl®, Marplan®, Nardil®, Parnate®)
• Do not drink alcohol while you are using this medicine.

Warnings While Using This Medicine

• Make sure your doctor knows if you have glaucoma, asthma, thyroid problems, or heart disease. Also make sure your doctor knows if you have high blood pressure, a stomach ulcer, or problems with urination or with your prostate. Tell your doctor if you are pregnant.
• This medicine may make you dizzy or drowsy. Avoid driving, using machines, or doing anything else that could be dangerous if you are not alert.

Possible Side Effects While Using This Medicine

Call your doctor right away if you notice any of these side effects:

• Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing.
• Lightheadedness or fainting.
• Painful sore on your skin where the needle is placed.
• Seizures.

If you notice these less serious side effects, talk with your doctor:

• Blurred vision.
• Change in how much or how often you urinate.
• Constipation, stomach upset.
• Dry nose, mouth, or throat.
• Feeling confused or excited.
• Problems with coordination.
• Thick mucus in your nose or throat.

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088