May increase risk of death in older adults with dementia-related conditions. May cause serious, irreversible movement disorder. May cause hyperglycemia; diabetics should check blood sugar levels regularly. May cause high cholesterol and triglyceride levels. Find emergency attention at once if you experience an allergic reaction, overdose symptoms, or serious drug reaction that affects many body parts. Contact doctor as soon as possible if you encounter serious effects such as: uncontrolled muscle movements, speech/swallowing problems, swelling in hands/feet, confusion, unusual moods/thought/behavior, sudden weakness/ill feeling, fever and flu symptoms, liver issue symptoms, high blood sugar symptoms, stiff muscles, uneven pulse, feeling faint. Other side effects may include: weight gain, appetite increase, headache, dizziness, drowsiness, fatigue, restlessness, speech/memory problems, tremors, numbness and tingling, personality changes, dry mouth or increased salivation, stomach pain, constipation, pain in limbs.