Common side effects (these can affect from 1 to 10 users in 100 patients treated) • Tiredness, trouble sleeping, anxiety, feeling agitated or having abnormal dreams. • Tremor or numbness, including numbness or tingling of the skin. • Diarrhoea, being sick (vomiting), heartburn, breaking wind, stomach pain. • Tinnitus (perception of sound in the ear when there is no external sound). • Blurred eyesight. • Feeling the heart pumping in the chest, flushing, increased sweating, night sweats • Problems getting an erection, less sex drive. • (Itchy) rash. • Muscle pain, muscle tightness, muscle spasm. • Increased yawning. • Lack of appetite, weight loss.