CLEMASTIN is an antihistamine. It works by blocking the action of histamine, reducing the symptoms of an allergic reaction.

They need to know if you have any of these conditions:

• glaucoma or increased pressure in the eye;
• a stomach ulcer;
• an enlarged prostate, bladder problems, or difficulty urinating;
• an overactive thyroid (hyperthyroidism);
• hypertension or any type of heart problems; or
• asthma

Take each dose with a full glass of water. Clemastine can be taken with or without food. Never take more of this medication than is prescribed for you. The maximum amount of clemastine that you should take in 1 day is 8.04 mg.

Take the missed dose as soon as you remember. However, if it is almost time for your next dose, skip the missed dose and take only your next regularly scheduled dose. Do not take a double dose of this medication unless otherwise directed by your doctor.

• monoamine oxidase inhibitors (MAOI)
• over-the-counter cough, cold, allergy, or insomnia medications
• anxiety or sleep medicines such as alprazolam (Xanax), diazepam (Valium), chlordiazepoxide (Librium), temazepam (Restoril), or triazolam (Halcion);
• medications for depression such as amitriptyline (Elavil), doxepin (Sinequan), nortriptyline (Pamelor), fluoxetine (Prozac), sertraline (Zoloft), or paroxetine (Paxil)
• any other medications that make you feel drowsy, sleepy or relaxed

Tell your prescriber or health care professional about all other medicines you are taking, including non-prescription medicines, nutritional supplements, or herbal products. Also tell your prescriber or health care professional if you are a frequent user of drinks with caffeine or alcohol, if you smoke, or if you use illegal drugs. These may affect the way your medicine works. Check with your health care professional before stopping or starting any of your medicines.

Use caution when driving, operating machinery, or performing other hazardous activities. Clemastine may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities. Use alcohol cautiously. Alcohol may increase drowsiness and dizziness while you are taking clemastine.

Clemastine is in the FDA pregnancy category B. This means that it is unlikely to harm an unborn baby. Do not take clemastine without first talking to your doctor if you are pregnant. Clemastine passes into breast milk. Infants are especially sensitive to the effects of antihistamines, and serious side effects could occur in a nursing baby. Clemastine is not recommended if you are breast-feeding a baby. Do not take clemastine without first talking to your doctor if you are nursing a baby. If you are over 60 years of age, you may be more likely to experience side effects from clemastine. You may require a lower dose of this medication.

Side effects that you should report to your prescriber or health care professional as soon as possible:

• allergic reaction (difficulty breathing; closing of your throat; swelling of your lips, tongue, or face; or hives)

Side effects that usually do not require medical attention (report to your prescriber or health care professional if they continue or are bothersome):

• sleepiness, fatigue, or dizziness;
• headache;
• dry mouth; or
• difficulty urinating or an enlarged prostate

This list may not describe all possible side effects.

Store clemastine at room temperature away from moisture and heat. Keep out of the reach of children. Never share your medicines with others.