Type of medicine: antihistamine
Generic and brand names: clemastine fumarate, oral; clemastine, oral; Tavist Allergy (There may be other brand names for this medicine.)
This medicine is taken by mouth to treat symptoms of colds and allergies such as sneezing, runny nose, watery eyes, itching, and rash.
It may also be used to treat itching and swelling due to hives.
Before taking this medicine, tell your healthcare provider if you have:
Do not take this medicine if you have taken MAO inhibitors such as phenelzine (Nardil), tranylcypromine (Parnate), or isocarboxazid (Marplan) within the past 2 weeks. Talk with your healthcare provider about this.
Females of childbearing age: Tell your healthcare provider if you are pregnant or plan to become pregnant. Do not breast-feed while taking this medicine without your healthcare provider's approval.
Check the label on the medicine for directions about your specific dose. Take this medicine exactly as your healthcare provider prescribes. Do not take more of it or take it more often than prescribed. Taking too much can make you very drowsy and can increase the risk of other side effects.
You may take this medicine with or without food. Taking it with meals may lessen the chance the drug will upset your stomach.
This medicine may come in different forms. If you have extended-release tablets or capsules, do not break, crush, or chew them. Swallow them whole. Ask your pharmacist if you have the extended-release tablets or capsules. If you are using the liquid, measure the correct dose with a special dose-measuring spoon or cup. You may need to shake the liquid medicine before taking it. Follow the directions on the label.
If you are using the dissolving strips, dissolving tablets, or chewable tablets, follow the directions on the medicine package for the proper way to take the medicine.
You can buy some forms of this medicine without a prescription. Follow the directions on the package exactly.
If you miss a dose, take it as soon as you remember unless it is almost time for the next scheduled dose. Do not take double doses. If you are not sure of what to do if you miss a dose, or if you miss more than one dose, contact your healthcare provider.
If you or anyone else has intentionally taken too much of this medicine, call 911 or go to the emergency room right away. If you pass out, have seizures, weakness or confusion, or have trouble breathing, call 911. If you think that you or anyone else may have taken too much of this medicine, call the poison control center. Do this even if there are no signs of discomfort or poisoning. The poison control center number is 800-222-1222.
Symptoms of an acute overdose may include: drowsiness, confusion, weakness, blurred vision, pinpoint or large pupils, dry mouth, cold clammy skin, flushing, hallucinations, restlessness, tremors, seizures.
Read the instructions on the medicine package carefully. Many prescription and nonprescription cold and allergy medicines may contain this medicine or a similar medicine. Check nonprescription medicine labels carefully before using two or more medicines at the same time. Taking these medicines together could result in an overdose. This is especially important when giving these medicines to young children. Do not give a child under age 4 any cough and cold medicines unless specifically instructed to do so by your healthcare provider. Talk with your healthcare provider about this.
This medicine may make you dizzy or drowsy. It may be best to take it at bedtime. When taken at bedtime, you may still be drowsy the next day. Do not drive or operate machinery unless you are fully alert.
Antihistamines increase the effects of alcohol and other drugs that slow down the nervous system. Do not drink alcohol or take other medicines unless your healthcare provider approves.
This medicine may make your skin more sensitive to the sun, which may lead to painful sunburns. While you are taking this medicine, avoid long exposure to the sun. Wear protective clothing, a hat, and sunscreen lotion when you need to be outdoors. Do not use a sunlamp. If you get a severe sunburn, contact your healthcare provider right away.
Adults over the age of 65 may be at greater risk for side effects. Talk with your healthcare provider about this.
Contact your healthcare provider if your condition does not improve in a few days or if it gets worse.
If you need emergency care, surgery, allergy skin tests, or dental work, tell the healthcare provider or dentist you are taking this medicine.
Along with its needed effects, your medicine may cause some unwanted side effects. Some side effects may be very serious. Some side effects may go away as your body adjusts to the medicine. Tell your healthcare provider if you have any side effects that continue or get worse.
Life-threatening (Report these to your healthcare provider right away. If you cannot reach your healthcare provider right away, get emergency medical care or call 911 for help): Allergic reaction (hives; itching; rash; trouble breathing; tightness in your chest; swelling of your lips, tongue, and throat); seizures.
Serious (report these to your doctor right away): Unusual weakness or tiredness, unexplained fever, sore throat, unusual bleeding or bruising, trouble urinating, irregular or pounding heartbeat, chest pain, hallucinations, severe unsteadiness.
Other: Drowsiness, trouble sleeping, dizziness, heavier phlegm, heartburn, nausea, loss of appetite, vomiting, dry mouth, sweating, headache, nervousness, confusion, blurred vision.
When you take this medicine with other medicines, it can change the way this or any of the other medicines work. Nonprescription medicines, vitamins, natural remedies, and certain foods, may also interact. Using these products together might cause harmful side effects. Talk to your healthcare provider if you are taking:
Do not drink alcohol while taking this medicine.
If you are not sure if your medicines might interact, ask your pharmacist or healthcare provider. Keep a list of all your medicines with you. List all the prescription medicines, nonprescription medicines, supplements, natural remedies, and vitamins that you take. Be sure that you tell all healthcare providers who treat you about all the products you are taking.
Store this medicine at room temperature. Keep the container tightly closed. Protect it from heat, high humidity, and bright light.
This advisory includes selected information only and may not include all side effects of this medicine or interactions with other medicines. Ask your healthcare provider or pharmacist for more information or if you have any questions.
Ask your pharmacist for the best way to dispose of outdated medicine or medicine you have not used. Do not throw medicine in the trash.
Keep all medicines out of the reach of children.
Do not share medicines with other people.
