What is Fluoxetine? Uses, warnings & side effects

How to take Fluoxetine

• Take your medicine as directed. Your dose may need to be changed several times to find what works best for you. 

• This medicine should come with a medication guide. Ask your pharmacist for a copy if you do not have one.

• You may need to take this medicine for a month or longer before you feel better. If you feel that the medicine is not working well, tell your doctor right away. Do not take more than your normal dose.

• Take fluoxetine doses at the same time each day.

• Fluoxetine doses can be taken with or without food.

• How to take fluoxetine tablets or capsules

  • Swallow the tablet or capsule whole with a glass of water.

  • Store fluoxetine tablets or capsules at room temperature away from light.

• How to take fluoxetine oral solution

  • You do not need to shake the bottle before measuring a dose.

  • Measure the dose using a calibrated oral syringe or similar calibrated device. 

  • Store fluoxetine oral solution at room temperature away from light.

What to do if you miss a dose of Fluoxetine

• Fluoxetine should be taken once per day in the morning.

• If you miss a dose or forget to take your medicine, take it as soon as you can on the day you were supposed to take it. 

• If the dose is remembered the next day, just skip the missed dose and take the next dose as scheduled in the morning. 

• Do not use extra medicine to make up for a missed dose.

Fluoxetine contraindications - Who shouldn't take Fluoxetine?

• This medicine is not right for everyone. 

• Do not use it if you have had an allergic reaction to fluoxetine.

Fluoxetine warnings

• Tell any doctor or other healthcare provider who treats you that you are using this medicine.

• Your doctor may need to do lab tests regularly to check your progress and any effects of the medicine. Keep all appointments.

• For some children, teenagers, and young adults, this medicine increases the risk of suicidal thoughts and behaviors. It may worsen depression or emotional problems. Talk with your doctor right away if you notice any thoughts or behavior changes that concern you. 

• Tell your doctor if you or anyone in your family has a history of bipolar disorder, mania, hypomania, other mental illnesses, or suicide attempts.

• Tell your doctor if you are pregnant or breastfeeding.

• Tell your doctor if you have:

  • Kidney disease

  • Liver disease

  • Bleeding problems

  • Diabetes

  • High blood pressure

  • Glaucoma

  • A history of seizures

  • Heart disease, including heart failure or a history of heart attacks

  • A heart rhythm problem (such as QT prolongation)

  • A history of stroke

• This medicine may cause the following problems:

  • Serotonin syndrome (may be life-threatening when used with certain other medicines)

  • Higher risk of bleeding

  • Vision problems

  • Seizures

  • Manic or hypomanic episodes

  • Low sodium levels in the blood

  • Heart rhythm changes

  • Changes in appetite or weight

  • Severe allergic reactions

• This medicine may make you dizzy or drowsy. Do not drive or do anything else that could be dangerous until you know how this medicine affects you.

• Do not stop using this medicine suddenly. Your doctor will need to slowly decrease your dose before you stop it completely.

Fluoxetine interactions & what to avoid when taking Fluoxetine

• To avoid potentially hazardous drug interactions, tell the prescribing healthcare provider about all prescription drugs, over-the-counter medications, and supplements you use before taking fluoxetine.

• Tell other healthcare providers you are using this medicine before they prescribe new medications.

• If you are using an MAO inhibitor (MAOI), do not start taking fluoxetine until you’ve stopped taking the MAO inhibitor for at least 14 days. Do not start an MAOI until you’ve stopped taking fluoxetine for 5 weeks.

• Fluoxetine should never be taken with the antipsychotic medications pimozide or thioridazine.

• Some medicines and foods can affect how fluoxetine works or increase the risk or severity of side effects. Alternatively, fluoxetine can change the effectiveness and safety of other drugs. Tell your doctor if you are taking:

  • Other antidepressants

  • Drugs that treat mental health conditions such as anxiety, mood problems, or psychosis

  • Amphetamines

  • Blood thinners

  • Drugs that treat heart rhythm problems

  • Drugs that make you pee (diuretics)

  • Migraine treatments called triptans

  • Phenothiazine drugs

  • NSAIDs such as aspirin or ibuprofen

  • The narcotic painkillers tramadol, fentanyl, methadone, or levomethadyl

  • The anti-seizure drugs carbamazepine or phenytoin

  • The antibiotics erythromycin, moxifloxacin, gatifloxacin, or sparfloxacin

  • The malaria drugs mefloquine or halofantrine

  • Dolasetron, tacrolimus, probucol, or pentamidine

  • The supplements St. John’s wort or tryptophan

• Do not drink alcohol while you are using this medicine.

• Tell your doctor if you use anything else that makes you sleepy. Some examples are allergy medicine, narcotic pain medicine, muscle relaxants, and alcohol.

Find more detailed information about fluoxetine interactions to avoid here.