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Clemastine

Precautions

Before taking clemastine, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: breathing problems (such as asthma, emphysema), a certain eye problem (glaucoma), heart problems, high blood pressure, liver disease, seizures, stomach problems (such as ulcers, blockage), overactive thyroid (hyperthyroidism), urination problems (such as trouble urinating due to enlarged prostate, urinary retention).

This drug may make you dizzy or drowsy or blur your vision. Alcohol or marijuana (cannabis) can make you more dizzy or drowsy. Do not drive, use machinery, or do anything that needs alertness or clear vision until you can do it safely. Limit alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).

Liquid preparations of this product may contain sugar and/or alcohol. Caution is advised if you have diabetes, alcohol dependence, or liver disease. Ask your doctor or pharmacist about the safe use of this product.

Older adults may be more sensitive to the side effects of this drug, especially drowsiness, constipation, problems urinating, or confusion. Drowsiness and confusion can increase the risk of falling.

Children may be more sensitive to the effects of antihistamines. In young children, this medication may cause agitation/excitement instead of drowsiness.

During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.

This drug passes into breast milk and may have undesirable effects on a nursing infant. Consult your doctor before breastfeeding.

Side Effects

Drowsiness, dizziness, headache, constipation, stomach upset, blurred vision, trouble walking/clumsiness, or dry mouth/nose/throat may occur. These effects may decrease as your body adjusts to the medication. If any of these effects last or get worse, contact your doctor or pharmacist promptly.

To relieve dry mouth, suck on (sugarless) hard candy or ice chips, chew (sugarless) gum, drink water, or use a saliva substitute. Clemastine can dry up and thicken mucus in your lungs, making it more difficult to breathe and clear your lungs. To help prevent this effect, drink plenty of fluids unless otherwise directed by your doctor.

To reduce the risk of dizziness and lightheadedness, get up slowly when rising from a sitting or lying position.

If your doctor has prescribed this medication, remember that your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if you have any serious side effects, including: mental/mood changes (such as hallucinations, irritability, nervousness, confusion), ringing in the ears, trouble urinating, easy bruising/bleeding, fast/irregular heartbeat, seizure.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

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Drug information is selected from data included with permission and copyrighted by First DataBank, Inc. This is a summary and does not contain all possible information about this product. For complete information about this product or your specific health needs, ask your healthcare professional. Always seek the advice of your healthcare professional if you have any questions about this product or your medical condition. This information is not intended as individual medical advice and does not substitute for the knowledge and judgment of your healthcare professional. This information does not contain any assurances that this product is safe, effective or appropriate for you.

This information is intended only for residents of the United States. Products sold under the same brand names in other countries may contain different ingredients.

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Information expires December 2024.