Citalopram can cause a serious movement problem called tardive dyskinesia. Call your doctor right away if you have any of the following symptoms: lip smacking or puckering, puffing of the cheeks, rapid or worm-like movements of the tongue, or other unusual mouth movements.
Stop taking this medication and call your doctor at once if you have a serious side effect such as:
confusion, hallucinations, unusual thoughts or behavior, or problems with memory, concentration, or speech;
chest pain, sudden shortness of breath, swelling in your hands or feet;
a light-headed feeling, like you might pass out;
low cortisol levels-nausea, vomiting, loss of appetite, dizziness, worsening tiredness or weakness; or
high blood pressure (severe headache, blurred vision, buzzing in your ears, anxiety, confusion, chest pain, shortness of breath, uneven heartbeats, seizure).
Less serious citalopram side effects may include:
drowsiness, dizziness, spinning sensation;
sleep problems (insomnia);
stuffy nose, sore throat, runny or stuffy nose, cough;
upset stomach, constipation;
dry mouth, or changes in appetite or weight;
tremor, restless feeling;
feeling anxious, nervous,