Anticholinergic effects can be produced by therapeutic doses although these can frequently be minimized or eliminated by careful dosage. They include: dryness of the mouth, mydriasis, blurring of vision, giddiness, lightheadedness, and gastrointestinal disturbances such as nausea, vomiting, epigastric distress, and constipation. Occasionally an allergic reaction such as a skin rash may be encountered. Feelings of muscular weakness may occur. Acute suppurative parotitis as a complication of dry mouth has been reported.