What side effects does Atomoxetine (Strattera) cause?

There are many possible side effects of atomoxetine. The most common include: nausea, vomiting, dry mouth, abdominal pain, headaches and decreased appetite. Other common effects include: fatigue, irritability, mood swings, jitteriness, shakiness, increased sweating, hot flashes, chills, constipation, indigestion or heartburn, difficulty passing urine, pain while urinating, impotence, decreased sexual drive, menstrual problems and weight loss.  Less common, but often more serious, side effects include: dizziness, lightheadedness, fainting, painful erection of the penis that does not go away (priapism), shortness of breath, chest pain or tightness, increased blood pressure, fast or irregular heart beat, sudden death, stroke, heart attack, liver damage, rash, seizures, confusion, suicidal thoughts, behavior changes (such as becoming more outgoing or aggressive), hallucinations, agitation, restlessness and allergic reactions (such as rash, itching, hives, wheezing, trouble with breathing or swelling).