This information from Lexicomp® explains what you need to know about this medication, including what it’s used for, how to take it, its side effects, and when to call your healthcare provider.
Brand Names: Canada
What is this drug used for?
- It is used to ease allergy signs.
- It is used to treat hives.
- It may be given to you for other reasons. Talk with the doctor.
What do I need to tell my doctor BEFORE I take this drug?
- If you are allergic to this drug; any part of this drug; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
- If you have ever had a long QT on ECG or other heartbeat that is not normal.
- If you are also taking any of these drugs: Cyclosporine, diltiazem, erythromycin, ketoconazole, rifampin, or ritonavir.
- If you are taking any drugs that can cause a certain type of heartbeat that is not normal (prolonged QT interval). There are many drugs that can do this. Ask your doctor or pharmacist if you are not sure.
- If you are taking any drugs that can cause electrolyte problems. There are many drugs that can do this. Ask your doctor or pharmacist if you are not sure.
This is not a list of all drugs or health problems that interact with this drug.
Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take this drug with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.
What are some things I need to know or do while I take this drug?
- Tell all of your health care providers that you take this drug. This includes your doctors, nurses, pharmacists, and dentists.
- Do not take more than what your doctor told you to take. Taking more than you are told may raise your chance of very bad side effects.
- Do not take this drug for longer than you were told by your doctor.
- Avoid driving and doing other tasks or actions that call for you to be alert until you see how this drug affects you.
- Talk with your doctor before you use alcohol, marijuana or other forms of cannabis, or prescription or OTC drugs that may slow your actions.
- If you drink grapefruit juice or eat grapefruit often, talk with your doctor.
- Different forms of this drug may be for use in different ages of children. Talk with the doctor before giving this drug to a child.
- Tell your doctor if you are pregnant, plan on getting pregnant, or are breast-feeding. You will need to talk about the benefits and risks to you and the baby.
What are some side effects that I need to call my doctor about right away?
WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:
- Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
- Slow heartbeat.
- Cold sweats.
- Upset stomach.
- Shortness of breath.
- A type of abnormal heartbeat (prolonged QT interval) has happened with this drug. Sometimes, this has led to another type of unsafe abnormal heartbeat (torsades de pointes). Call your doctor right away if you have a fast or abnormal heartbeat, or if you pass out.
What are some other side effects of this drug?
All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:
- Feeling dizzy or sleepy.
- Stomach pain.
Dispersible tablets and liquid (solution):
- Eye irritation.
- Nose irritation.
- Feeling tired or weak.
These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.
You may report side effects to your national health agency.
You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.
How is this drug best taken?
Use this drug as ordered by your doctor. Read all information given to you. Follow all instructions closely.
- Take on an empty stomach. Take at least 1 hour before or 2 hours after eating food or drinking fruit juice.
- Take with a full glass of water.
- If needed, you can break the tablet in half to make it easier to swallow. Be sure to take the whole tablet as a single dose.
- Take by mouth only.
- Let dissolve in your mouth. Water is not needed.
- If needed, you may mix the tablet in a teaspoon of water. Do not mix in grapefruit juice or other fruit juices. After the dose is taken, make sure none of the tablet is left in the spoon.
- Measure liquid doses carefully. Use the measuring device that comes with this drug. If there is none, ask the pharmacist for a device to measure this drug.
What do I do if I miss a dose?
- Take a missed dose as soon as you think about it.
- If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
- Do not take 2 doses at the same time or extra doses.
How do I store and/or throw out this drug?
- Store at room temperature in a dry place. Do not store in a bathroom.
- Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
- Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.
General drug facts
- If your symptoms or health problems do not get better or if they become worse, call your doctor.
- Do not share your drugs with others and do not take anyone else’s drugs.
- Some drugs may have another patient information leaflet. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
- Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
- If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.
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