Thanks for asking. Two tablets of Celexa (Citalopram) should not give rise to major side effects in a 3 year old. However, the side effects could be- * drowsiness, dizziness, weakness * anxiety, feeling shaky, sleep problems * vision changes * nausea, loss of appetite, diarrhea, constipation * dry mouth, yawning * cold symptoms such as stuffy nose, sneezing, sore throat, cough * increased sweating I do not expect long term side effects. If present, long term side effects could include: * changes in weight I would insist you not to worry, especially because she has already been taken to the ER where the doctors can take appropriate interventions if required. Hope that helps.