ZzzQuil

Generic Name: diphenhydramine (DYE fen HYE dra meen)
Brand Name: Allergy Relief (Diphenhydramine HCl), Allermax, Banophen, Benadryl, Compoz Nighttime Sleep Aid, Diphedryl, Diphenhist, Dytuss, Nytol QuickCaps, PediaCare Children's Allergy, Q-Dryl, QlearQuil Nightitme Allergy Relief, Quenalin, Scot-Tussin Allergy Relief Formula, Siladryl Allergy, Silphen Cough, Simply Sleep, Sleepinal, Sominex, Tranquil, Twilite, Unisom Sleepgels Maximum Strength, Valu-Dryl, Vanamine PD, Z-Sleep, ZzzQuil

Medically reviewed by Drugs.com on Jan 20, 2020 – Written by Cerner Multum

• Overview
• Side Effects
• Dosage
• Interactions
• Pregnancy
• More

What is ZzzQuil?

ZzzQuil is an antihistamine that reduces the effects of natural chemical histamine in the body.

ZzzQuil is used as a sleep-aid for the relief of occasional sleeplessness, and to reduce the time it takes to fall asleep if you have difficulty falling asleep.

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

Important Information

You should not use antihistamine medication to make a child sleepy.

Before taking this medicine

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

This medicine is not for use in children under the age of 12 years.

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

• blockage in your digestive tract (stomach or intestines);

• bladder obstruction or other urination problems;

• a colostomy or ileostomy;

• liver or kidney disease;

• asthma, chronic obstructive pulmonary disease (COPD), or other breathing disorder;

• cough with mucus, or cough caused by smoking, emphysema, or chronic bronchitis;

• heart disease, low blood pressure;

• glaucoma;

• a thyroid disorder; or

• if you take potassium (Cytra, Epiklor, K-Lyte, K-Phos, Kaon, Klor-Con, Polycitra, Urocit-K).

It is not known whether ZzzQuil will harm an unborn baby. Ask a doctor before using this medicine if you are pregnant.

Diphenhydramine can pass into breast milk and may harm a nursing baby. Antihistamines may also slow breast milk production. Ask a doctor before using this medicine if you are breast-feeding.

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

How should I take ZzzQuil?

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.

Do not give this medication to a child younger than 12 years old.

You should not use antihistamine medication to make a child sleepy.

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

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

Call your doctor if your symptoms do not improve after 7 days of treatment, or if you have a fever with a headache, cough, or skin rash.

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

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Since ZzzQuil is used when needed, you may not be on a dosing schedule. If you are on a schedule, use the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not use 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 ZzzQuil?

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.

Ask a doctor or pharmacist before using any other cold, cough, allergy, or sleep medicine. Antihistamines are contained in many combination medicines. Taking certain products together can cause you to get too much of this type of medicine. Check the label to see if a medicine contains an antihistamine.

ZzzQuil side effects

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

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

• pounding heartbeats or fluttering in your chest;

• painful or difficult urination;

• little or no urinating;

• confusion, feeling like you might pass out; or

• tightness in your neck or jaw, uncontrollable movements of your tongue.

Common side effects may include:

• dizziness, drowsiness, loss of coordination;

• dry mouth, nose, or throat;

• constipation, upset stomach;

• dry eyes, blurred vision; or

• day-time drowsiness or "hangover" feeling after night-time use.

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.

What other drugs will affect ZzzQuil?

Ask a doctor or pharmacist before using ZzzQuil if you are also using any other drugs, including prescription and over-the-counter medicines, vitamins, and herbal products. Some medicines can cause unwanted or dangerous effects when used together. Not all possible interactions are listed in this medication guide.

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

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.