Before using it, 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. If you are wearing contact lenses, remove them before using this medication. Ask your doctor when you may replace your contact lenses. Before using this medication, tell your doctor or pharmacist your medical history, especially of personal or family history of glaucoma (angle-closure type), high blood pressure, overactive thyroid (hyperthyroidism), diabetes, heart disease (e.g., irregular heart rhythm, coronary artery disease), Down's syndrome, brain damage or spastic paralysis (in children). Antihistamines (e.g., diphenhydramine, meclizine), antispasmodics (e.g., dicyclomine), certain anti-arrhythmic drugs (e.g., quinidine), certain drugs for Parkinson's disease (e.g., anticholinergics such as benztropine, trihexyphenidyl), MAO inhibitors (isocarboxazid, linezolid, methylene blue, moclobemide, phenelzine, procarbazine, rasagiline, safinamide, selegiline, tranylcypromine), other eye medications, tricyclic antidepressants (e.g., amitriptyline).