It is important that your doctor check your progress at regular visits, to make sure this medicine is working properly. Blood tests may be needed to check for unwanted effects.
Do not take fluoxetine with a monoamine oxidase (MAO) inhibitor (eg, isocarboxazid [Marplan®], linezolid [Zyvox®], methylene blue injection, phenelzine [Nardil®], selegiline [Eldepryl®], tranylcypromine [Parnate®]). Do not start taking fluoxetine during the 2 weeks after you stop a MAO inhibitor and wait 5 weeks after stopping fluoxetine before you start taking a MAO inhibitor. If you take them together or do not wait the proper amount of time, you may develop confusion, agitation, restlessness, stomach or intestinal symptoms, a sudden high body temperature, an extremely high blood pressure, or severe convulsions.
Do not take thioridazine (Mellaril®) with fluoxetine and wait 5 weeks after stopping fluoxetine before you start taking thioridazine. Do not use pimozide (Orap®) with fluoxetine. Using these medicines together can cause very serious heart problems.
Fluoxetine may cause a serious condition called serotonin syndrome if taken together with some medicines. Do not use fluoxetine with buspirone (Buspar®), fentanyl (Abstral®, Duragesic®), lithium (Eskalith®, Lithobid®), tryptophan, St. John's wort, amphetamines, or some pain or migraine medicines (eg, rizatriptan, sumatriptan, tramadol, Frova®, Imitrex®, Maxalt®, Relpax®, Ultram®, Zomig®). Check with your doctor first before taking any other medicines with fluoxetine.
Fluoxetine may cause some teenagers and young adults to be agitated, irritable, or display other abnormal behaviors. It may also cause some people to have suicidal thoughts and tendencies or to become more depressed. Some people may have trouble sleeping, get upset easily, have a big increase in energy, or start to act reckless. If you or your caregiver notice any of these unwanted effects, tell your doctor right away. Let the doctor know if you or anyone in your family has bipolar disorder (manic-depressive) or has tried to commit suicide.
Do not suddenly stop taking this medicine without checking first with your doctor. Your doctor may want you to gradually reduce the amount you are using before stopping it completely. This will decrease the chance of having withdrawal symptoms such as agitation, breathing problems, chest pain, confusion, diarrhea, dizziness or lightheadedness, fast heartbeat, headache, increased sweating, muscle pain, nausea, restlessness, runny nose, trouble sleeping, trembling or shaking, unusual tiredness or weakness, vision changes, or vomiting.
Tell your doctor right away if you develop a rash or hives, swelling of the face, eyes, or mouth, or trouble breathing after taking this medicine.
This medicine may increase your risk for bleeding problems. Make sure your doctor knows if you are also taking other medicines that thin the blood, such as aspirin, nonsteroidal antiinflammatory agents, also called NSAIDs (eg, diclofenac, ibuprofen, naproxen, Advil®, Aleve®, Celebrex®, Voltaren®), or warfarin (Coumadin®, Jantoven®).
Hyponatremia (low sodium in the blood) may occur with this medicine. Check with your doctor right away if you have confusion, difficulty concentrating, headaches, memory problems, weakness, and unsteadiness.
Contact your doctor right away if you have dizziness, fainting, or a fast, pounding, or uneven heartbeat. Make sure your doctor knows if you have ever had a heart rhythm problem, such as QT prolongation, or if you or a family member has had a heart attack, heart failure, low blood pressure, or a stroke.
The use of alcohol is not recommended in patients who are taking fluoxetine.
This medicine may affect blood sugar levels. If you are diabetic and notice a change in the results of your blood or urine sugar tests, check with your doctor.
This medicine may cause some people to become drowsy or less able to think clearly, or to have poor muscle control. Make sure you know how you react to fluoxetine before you drive, use machines, or do anything else that could be dangerous if you are not alert and well able to control your movements.
Check with your doctor right away if you have decreased interest in sexual intercourse, delayed or inability to have an orgasm in women, inability to have or keep an erection in men, or loss in sexual ability, desire, drive, or performance. These could be symptoms of sexual dysfunction.
Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal (eg, St. John's wort) or vitamin supplements.