Common side effects: affect 1 to 10 users in 100 • Changes in the levels of some blood cells and circulating fats. • Increases in the level of sugars in the blood and urine. • Feeling more hungry. • Dizziness. • Restlessness. • Tremor. • Muscle stiffness or spasm (including eye movements). • Problems with speech. • Unusual movement (especially of the face or tongue). • Constipation. • Dry mouth. • Rash. • Loss of strength. • Extreme tiredness. • Water retention leading to swelling of the hands, ankles or feet. • In the early stages of treatment, some people may feel dizzy or faint (with a slow heart rate), especially when getting up from a lying or sitting position.