HTN, heart disorders, thyroid disease, glaucoma, prostate hypertrophy, emphysema. Patients w/ impaired liver & kidney functions, DM, increased intraocular tension. Debility & hypoxia patients. May cause resp & CNS depression in large doses or in patients w/ resp disorders (eg, asthma, emphysema). Discontinue if insomnia, palpitation & dizziness occur. May impair the ability to drive the vehicle or operate the machinery. Pregnancy & lactation.