Generic Name: clemastine (KLEM-ass-teen)
Brand Name: Examples include Allerhist-1 and Tavist-1
Allerhist-1 is used for:
Preventing or treating symptoms of hay fever and other upper respiratory allergies or the common cold, such as runny nose, sneezing, itching of the nose and throat, and itchy, watery eyes, and relieving cough. It may also be used for other conditions as determined by your doctor.
Allerhist-1 is an antihistamine. It works by blocking the action of histamine, reducing the symptoms of an allergic reaction.
Do NOT use Allerhist-1 if:
- you are allergic to any ingredient in Allerhist-1 or other similar medicines
- you are taking sodium oxybate (GHB)
- you are currently taking or have taken a monoamine oxidase (MAO) inhibitor (eg, phenelzine) in the past 14 days
- you are breast-feeding
Contact your doctor or health care provider right away if any of these apply to you.
Before using Allerhist-1:
Some medical conditions may interact with Allerhist-1. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:
- if you are pregnant, planning to become pregnant, or are breast-feeding
- if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
- if you have allergies to medicines, foods, or other substances
- if you have asthma, chronic obstructive pulmonary disease (COPD), chronic bronchitis, emphysema, lung disease, shortness of breath, or sleep apnea
- if you have blockage of the stomach, intestine, or urinary tract; difficulty urinating; diabetes; ulcers; enlargement of the prostate; glaucoma; heart disease; high blood pressure; porphyria; or thyroid disease
Some MEDICINES MAY INTERACT with Allerhist-1. Tell your health care provider if you are taking any other medicines, especially any of the following:
- Sodium oxybate (GHB) because an increase in sleep duration and a decrease in the ability to breathe are likely to occur
- MAO inhibitors (eg, phenelzine) because they can cause serious, sometimes fatal, reactions
This may not be a complete list of all interactions that may occur. Ask your health care provider if Allerhist-1 may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.
How to use Allerhist-1:
Use Allerhist-1 as directed by your doctor. Check the label on the medicine for exact dosing instructions.
- Allerhist-1 may be taken with or without food.
- Use Allerhist-1 exactly as directed on the package, unless instructed differently by your doctor. If you are taking Allerhist-1 without a prescription, follow any warnings and precautions on the label.
- If you miss a dose of Allerhist-1 and you are taking it regularly, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.
Ask your health care provider any questions you may have about how to use Allerhist-1.
Important safety information:
- Allerhist-1 may cause drowsiness or dizziness. Do not drive, operate machinery, or do anything else that could be dangerous until you know how you react to Allerhist-1. Using Allerhist-1 alone, with certain other medicines, or with alcohol may lessen your ability to drive or perform other potentially dangerous tasks.
- Avoid drinking alcohol or taking other medications that cause drowsiness (eg, sedatives, tranquilizers) while taking Allerhist-1. Allerhist-1 will add to the effects of alcohol and other depressants. Ask your pharmacist if you have questions about which medicines are depressants.
- Allerhist-1 may cause dizziness. Alcohol, hot weather, exercise, and fever can increase this effect. To prevent it, sit up or stand slowly, especially in the morning. Also, sit or lie down at the first sign of dizziness.
- Do not become overheated in hot weather or during exercise or other activities since heatstroke may occur.
- Do not use Allerhist-1 with any other medicine that contains clemastine. Before you begin taking any new prescription or over-the-counter medicine, including one used on the skin, read the ingredients to see if it also contains clemastine. If it does, or if you are uncertain if it does, contact your doctor or pharmacist.
- Do not use Allerhist-1 for persistent or chronic cough, such as that occurs with smoking, asthma, or emphysema, or if the cough is accompanied by excessive mucus, unless directed by a health care provider.
- If you are using Allerhist-1 for cough, cold, or allergy symptoms, stop use and contact your doctor if your symptoms do not improve within 7 days or are accompanied by fever.
- Use Allerhist-1 with caution in the ELDERLY because they may be more sensitive to its effects, especially dizziness, sedation, and lightheadedness upon standing.
- Use Allerhist-1 with extreme caution in CHILDREN. Talk to your doctor or pharmacist if you have any questions about the brand you are using.
- PREGNANCY and BREAST-FEEDING: If you become pregnant, discuss with your doctor the benefits and risks of using Allerhist-1 during pregnancy. Allerhist-1 is excreted in breast milk. Do not breast-feed while taking Allerhist-1.
Possible side effects of Allerhist-1:
All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:
Seek medical attention right away if any of these SEVERE side effects occur:
Dizziness; drowsiness; dry mouth, throat, and nose; excitability; thickening of mucus in nose or throat.
Severe allergic reactions (rash; hives; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); convulsions; fast heartbeat or pounding in the chest; decreased alertness; hallucinations; tremor; wheezing.
This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.
If OVERDOSE is suspected:
Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately. Symptoms may include coma; excitement; hallucinations; loss of consciousness; muscle twitching; seizures; tremor; weakness.Proper storage of Allerhist-1:
Store Allerhist-1 at room temperature, between 68 and 77 degrees F (20 and 25 degrees C), or according to directions on the package label. Store in the original package or container. Store away from heat, moisture, and light. Do not store in the bathroom. Keep Allerhist-1 out of the reach of children and away from pets.
- If you have any questions about Allerhist-1, please talk with your doctor, pharmacist, or other health care provider.
- Allerhist-1 is to be used only by the patient for whom it is prescribed. Do not share it with other people.
- If your symptoms do not improve or if they become worse, check with your doctor.
- Check with your pharmacist about how to dispose of unused medicine.
This information should not be used to decide whether or not to take Allerhist-1 or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about Allerhist-1. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to Allerhist-1. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using Allerhist-1.
Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using this medicine.