Diphedryl

Diphedryl is an antihistamine used to treat sneezing, runny nose, watery eyes, hives, skin rash, itching, and other cold or allergy symptoms.

Diphedryl is also used to treat motion sickness, help with sleep, and address certain symptoms of Parkinson's disease. This sleep aid is not for use in children younger than 12 years old.

There are many brands and forms of diphenhydramine available. Not all brands are included in this leaflet.

Diphedryl may also be used for reasons not mentioned in this medication guide.

Use exactly as directed on the label, or as prescribed by your doctor. Diphedryl is only for short-term use until your symptoms clear up.

Taking too much Diphedryl can lead to serious heart problems, seizures, coma, or death.

Always follow directions on the medicine label about giving Diphedryl to a child. Do not use the medicine only to make a child sleepy. Death can occur from the misuse of antihistamines in very young children.

For motion sickness, take Diphedryl 30 minutes before you will be in a situation that causes you motion sickness (such as a long car ride, airplane or boat travel, amusement park rides, etc). Continue taking this medicine with meals and at bedtime for the rest of the time you will be in a motion-sickness situation.

As a sleep aid, take Diphedryl within 30 minutes before bedtime.

You must chew the chewable tablet before you swallow it.

Measure liquid medicine carefully. Use the dosing syringe provided, or use a medicine dose-measuring device (not a kitchen spoon).

Remove an orally disintegrating tablet from the package only when you are ready to take the medicine. Place the tablet in your mouth and allow it to dissolve, without chewing. Swallow several times as the tablet dissolves.

Call your doctor if the condition you are treating with Diphedryl does not improve, or if you have a fever with a headache, cough, or skin rash.

Do not use Diphedryl for longer than 2 weeks to treat sleep problems, or longer than 7 days to treat cold or allergy symptoms.

Diphedryl can affect the results of allergy skin tests. Tell any doctor who treats you that you are using Diphedryl.

Store at room temperature away from moisture and heat.

Use Diphedryl exactly as directed. Taking too much Diphedryl can cause serious heart problems, seizures, coma, or death.

Do not use this medicine to make a child sleepy. Diphedryl sleep aid medicine is not for use in children younger than 12 years old.

You should not use Diphedryl if you are allergic to it.

Ask a doctor or pharmacist if this medicine is safe to use if you have ever had:

• an enlarged prostate or problems with urination;
• asthma, chronic obstructive pulmonary disease (COPD), or another breathing issue;
• glaucoma; or
• a thyroid condition.

Ask a doctor before using this medicine if you are pregnant or breastfeeding. Diphedryl may slow down breast milk production.

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

Diphedryl may cause serious side effects. Stop using Diphedryl and call your doctor right away if you experience:

• severe drowsiness; or
• painful or difficult urination.

Side effects like dry mouth, constipation, and confusion may happen more often in older adults.

Common side effects of Diphedryl may include:

• drowsiness;
• dry eyes, blurred vision;
• dry mouth, nose, or throat;
• decreased urination;
• constipation;
• feeling restless or excited (especially in children); or
• daytime drowsiness or a "hangover" feeling after using it at night.

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 the FDA at 1-800-FDA-1088.

Since Diphedryl is taken as needed, you might not have a regular dosing schedule. If you miss a dose and it's almost time for your next dose, just skip the missed dose. Do not take two doses at the same time.

Seek emergency medical help or call the Poison Help line at 1-800-222-1222. Taking too much diphenhydramine can be fatal.

Signs of an overdose may include vomiting, confusion, severe drowsiness, ringing in your ears, no urination, very dry eyes and mouth, dilated pupils, fast heartbeats, tremors, agitation, hallucinations, or seizures.

Do not drive or do anything dangerous until you know how Diphedryl will affect you. Your reactions may be impaired.

Drinking alcohol can increase some side effects of diphenhydramine.

Ask a doctor or pharmacist before using any other medicine that may contain Diphedryl. This includes medicines for sleep, cold/allergy symptoms, or anti-itch medicine for the skin. Taking too much of this medicine may lead to a fatal overdose.

Ask a doctor or pharmacist before using Diphedryl with any other medicines, especially those that can cause drowsiness (such as opioid medication, sleep medicine, a muscle relaxer, or medicine for anxiety or seizures). Inform your doctor about all your current medicines and any medicine you begin or stop using. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed here.