Histex Syrup is an antihistamine that is used to treat sneezing, runny nose, itchy nose and throat, and itchy or watery eyes caused by allergies such as hay fever.

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

Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

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

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

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

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).

Call your doctor if your symptoms do not improve after 7 days, or if you have a fever, rash, or headaches.

If you need surgery or medical tests, tell the doctor ahead of time if you have taken this medicine within the past few days.

Store at room temperature away from moisture and heat. Do not allow liquid medicine to freeze.

You should not use Histex Syrup if you are allergic to it.

Ask a doctor or pharmacist if Histex Syrup is safe to use if you have:

• a breathing disorder such as chronic bronchitis or emphysema;

• glaucoma; or

• an enlarged prostate and urination problems.

Ask a doctor before using this medicine if you are pregnant or breastfeeding.

This medicine may contain phenylalanine. Check the medication label if you have phenylketonuria (PKU).

Since Histex Syrup is used when needed, you may not be on a dosing schedule. Skip any missed dose if it's almost time for your next dose. Do not use two doses at one time.

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

Avoid driving or hazardous activity until you know how Histex Syrup will affect you. Your reactions could be impaired.

Drinking alcohol can increase certain side effects of triprolidine.

Ask a doctor or pharmacist before using other cough or cold medicines that may contain similar ingredients.

Avoid becoming overheated or dehydrated during exercise and in hot weather. Histex Syrup can decrease sweating and you may be more prone to heat stroke.

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

Histex Syrup may cause serious side effects. Stop using Histex Syrup and call your doctor at once if you have:

• painful or difficult urination.

Common side effects of Histex Syrup may include:

• dizziness, drowsiness;

• blurred vision;

• dry mouth, nose, or throat;

• constipation;

• increased urination; or

• feeling nervous or restless (especially in children).

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.

Avoid using this medicine with other drugs that cause drowsiness or slow your breathing (such as opioid medicine, a muscle relaxer, or medicine for anxiety or seizures). Ask a doctor or pharmacist before using any other medication, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed in this medication guide.