There are a number of important precautions and warnings with citalopram to be aware of, including serious side effects to look out for. Citalopram may potentially cause gastrointestinal bleeding, suicidal thoughts or behavior, or seizures in some people. Do not take citalopram if you are allergic to any components of the medicine, have taken an MAOI within the past two weeks, or are currently taking pimozide.

• Bipolar disorder or a family history of bipolar disorder (manic depression)
• A history of suicide attempts or suicidal thoughts
• Had a recent heart attack or have unstable heart disease
• Seizures or epilepsy
• Liver disease, including liver failure or cirrhosis
• Kidney problems, including kidney failure (renal failure)
• Any allergies, including allergies to food, dyes, or preservatives.
   

• Pregnant or thinking of becoming pregnant
• Breastfeeding.
   

• Antidepressants (including citalopram) may increase the risk of suicidal thinking or behavior in children, teenagers, and adults (see Depression and Suicide for more information). Therefore, if you notice any changes in symptoms or new symptoms, talk to your healthcare provider immediately. Some of these symptoms may include: anxiety, hostility, agitation, panic, restlessness, hallucinations, extreme hyperactivity, and suicidal thinking or behavior (see Celexa and Suicide for more information).
   
• Before prescribing citalopram for depression, your healthcare provider should make sure that you do not have bipolar disorder (instead of depression). Sometimes, the symptoms of bipolar disorder and depression are very similar, and citalopram can cause problems in people with bipolar disorder.
   
• If you have a seizure disorder, there is a possibility that taking citalopram may cause seizures. Talk to your healthcare professional before taking citalopram if you have seizures.
   
• If you are stopping citalopram, you should be monitored by a healthcare professional for citalopram withdrawal symptoms. If you do develop any symptoms of a withdrawal, such as irritability, anxiety, confusion, headache, lethargy, or insomnia, your healthcare provider may slow down the rate at which the citalopram is stopped (see Citalopram Withdrawal).
   
• Citalopram may cause bleeding in the stomach or intestines. This risk is increased in those taking aspirin or nonsteroidal anti-inflammatory drugs (NSAIDS), such as ibuprofen. Symptoms of gastrointestinal bleeding may include:

o Bright red blood coating the stool

o Dark blood mixed with the stool

o Black or tarry stool

o Bright red blood in vomit

o Vomit that has the appearance of coffee grounds.

If you experience any of these symptoms, call your healthcare provider.

• If you are elderly or taking a diuretic, citalopram could cause low salt levels in the blood (hyponatremia). This generally returns to "normal" when you stop using the medication.
   
• If you have liver or kidney problems, you may need a lower citalopram dose (since the liver and kidneys help remove citalopram from the blood).
   
• Citalopram may affect your ability to perform complex tasks requiring mental and motor skills. Therefore, it is recommended that you become accustomed to its effect on you before becoming involved in activities requiring mental or motor concentration (such as driving a car or operating machinery).
   
• Citalopram can interact with certain medications (see Drug Interactions With Citalopram).
   
• Citalopram is a considered a pregnancy Category C medication. This means that citalopram may not be safe to use during pregnancy. Talk to your healthcare provider about the risks and benefits of using citalopram during pregnancy (see Celexa and Pregnancy for more information).
   
• Citalopram passes through breast milk. Therefore, if you are breastfeeding or plan to start breastfeeding, be sure to talk with your healthcare provider about using citalopram (see Celexa and Breastfeeding for more information).