Get emergency medical help if you have signs of an allergic reaction: skin rash or hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Report any new or worsening symptoms to your doctor, such as: mood or behavior changes, anxiety, panic attacks, trouble sleeping, or if you feel impulsive, irritable, agitated, hostile, aggressive, restless, hyperactive (mentally or physically), more depressed, or have thoughts about suicide or hurting yourself. Call your doctor at once if you have: blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights; racing thoughts, unusual risk-taking behavior, feelings of extreme happiness or sadness; pain or burning when you urinate; (in a child taking escitalopram) slow growth or weight gain; low levels of sodium in the body--headache, confusion, slurred speech, severe weakness, vomiting, loss of coordination, feeling unsteady; or severe nervous system reaction--very stiff (rigid) muscles, high fever, sweating, confusion, fast or uneven heartbeats, tremors, feeling like you might pass out. Seek medical attention right away if you have symptoms of serotonin syndrome, such as: agitation, hallucinations, fever, sweating, shivering, fast heart rate, muscle stiffness, twitching, loss of coordination, nausea, vomiting, or diarrhea. Common side effects may include: painful urination; dizziness, drowsiness, tiredness, weakness; feeling anxious or agitated; increased muscle movements, feeling shaky; sleep problems (insomnia); sweating, dry mouth, increased thirst, loss of appetite; nausea, constipation; yawning; nosebleed, heavy menstrual periods; or decreased sex drive, impotence, or difficulty having an orgasm. This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.