Before starting a new medication, make sure to go over all of the drug's precautions and warnings. With fluoxetine, you should look out for any symptoms of serotonin syndrome, be aware of certain drug interactions, and consult your doctor if you are breastfeeding. Fluoxetine is not suitable for everyone; do not take the medication if you are allergic to any components of the drug, have taken an MAOI within the past two weeks, or are also taking pimozide or thioridazine.

• 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 if you have heart disease
• Diabetes
• Seizures or epilepsy
• Suicidal thoughts
• Liver disease, including liver failure or cirrhosis
• Any allergies, including allergies to food, dyes, or preservatives.
   

• Pregnant or thinking of becoming pregnant
• Breastfeeding.
   

 

• Antidepressants (including fluoxetine) 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 Prozac and Suicide for more information).
   
• Before prescribing fluoxetine 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 fluoxetine can cause problems in people with bipolar disorder.
   
• Fluoxetine can cause rashes or other allergic reactions. If you develop an unexplained rash or hives, talk to your healthcare provider.
   
• Taking fluoxetine with other medications that affect serotonin can increase your risk of a developing a dangerous group of symptoms called serotonin syndrome. These other medications include other antidepressants, triptans (migraine medications), and several other medications (see Drug Interactions With Fluoxetine for more information). Contact your healthcare provider immediately if you have any possible symptoms of serotonin syndrome, including:

o Confusion

o Seeing or hearing things that are not really there (hallucinations)

o Fast heartbeat (tachycardia)

o Feeling faint

o Fever

o Sweating

o Muscle spasms

o Difficulty walking

o Diarrhea.

• Fluoxetine can cause insomnia and anxiety. Talk to your healthcare provider if you are experiencing problems sleeping or anxiety while taking fluoxetine.
   
• There is a possibility that fluoxetine may cause unwanted weight loss (see Prozac and Weight Loss).
   
• If you have a seizure disorder, there is a possibility that taking fluoxetine may cause seizures. Talk to your healthcare professional before taking fluoxetine if you have seizures.
   
• If you are stopping fluoxetine, you should be monitored by a healthcare professional for fluoxetine withdrawal symptoms. If you do develop any withdrawal symptoms, such as irritability, anxiety, confusion, headache, lethargy, or insomnia, your healthcare provider may slow down the rate at which the fluoxetine is stopped. However, the antidepressant may be less likely than other medications to cause withdrawal symptoms because it stays in your system for such a long time (see Prozac Withdrawal).
   
• Fluoxetine 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, fluoxetine could cause low salt levels in the blood (hyponatremia). This generally returns to "normal" when fluoxetine is discontinued.
   
• If you have liver problems, you may need a lower fluoxetine dose, since the liver helps to remove fluoxetine from the blood.
   
• Fluoxetine stays in your system for a long time. This means that you may not see the effects of a change in dose for several weeks.
   
• Fluoxetine 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).
   
• Fluoxetine can interact with certain medications (see Drug Interactions With Fluoxetine).
   
• Fluoxetine is a considered a pregnancy Category C medication. This means that it may not be safe to use during pregnancy. Talk to your healthcare provider about the risks and benefits of using fluoxetine during pregnancy (see Prozac and Pregnancy for more information).
   
• Fluoxetine passes through breast milk. Therefore, if you are breastfeeding or plan to start breastfeeding, be sure to talk with your healthcare provider about using fluoxetine (see Fluoxetine and Breastfeeding).