Following are the common side effects: Difficulty sleeping, Dizziness, Drooling, Drowsiness, Fatigue, Nausea, Severe dizziness when standing or sitting from a lying position, Stomach pain, Vomiting, Weakness Check with your doctor as soon as possible if any of the following side effects occur: Agitation, Confusion, disorientation, Difficulty swallowing, Increasing restlessness, Irritability, Signs of depression (poor concentration, changes in weight, changes in sleep, decreased interest in activities, thoughts of suicide), Signs of parkinsonism (tremor, muscle stiffness, difficulty starting movement, decrease in facial expressions, speech problems), Stop taking the medication and seek medical help immediately if any of the following symptoms occur:, Signs of heartbeat problems (dizziness, sensation of a pounding or irregular heartbeat, fainting, or seizures), Signs of neuroleptic malignant syndrome (high fever, muscle stiffness, confusion, profuse sweating, racing or irregular heartbeat), Signs of a serious allergic reaction (abdominal cramps, difficulty breathing, nausea and vomiting, or swelling of the face and throat)