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Terms Of Use


Brand Name(s) : Prozac, Oxactin, Prozep
Side Effects


Fluoxetine should be used with caution in:

It should not be used in:

  • Patients who are allergic to fluoxetine or to any other ingredients contained in the medicine
  • During the manic phase of patients with bipolar disorder
  • Patients who are being treated for depression with a mono-amine oxidase inhibitor (MAOIs) or have taken them in the last two weeks. Examples of MAOIs include moclobemide, phenelzine, tranylcypromine and isocarboxazid.

Also see list of precautions and interactions


Do not store above 30ºC (Prozac)

Do not store above 25ºC (generic)


  • Fluoxetine is used to help relieve depression by altering the amount of serotonin in the brain. Serotonin is one of many chemical compounds found in the brain which act as neurotransmitters or chemical messengers between nerve cells. Serotonin has a number of actions in the brain including regulation of mood.
  • Fluoxetine is a selective serotonin re-uptake inhibitor antidepressant, sometimes known as an SSRI.
  • It is used to relieve the symptoms of depression.
  • Benefits of being on this drug can include improvement in mood in patients who are feeling depressed.

Listed below are the typical uses of fluoxetine.

On occasion your doctor may prescribe this medicine to treat a condition not on the above list. Such conditions are listed below.


How often do I take it?

  • Take this medication orally usually once a day, with or without food. The capsules should be swallowed whole with a glass of water.
  • Use this medication regularly in order to get the most benefit from it.
  • Remember to use it at the same time each day - unless specifically told otherwise by your doctor.
  • It may take up to a few weeks before the full benefit of this drug takes effect.
  • Certain medical conditions may require different dosage instructions as directed by your doctor.

What dose?

  • Dosage is based on your age, gender, medical condition, response to therapy, and use of certain interacting medicines. Your doctor may decide to increase or decrease your dose of fluoxetine depending on your response to treatment.

Do I need to avoid anything?

  • Fluoxetine may affect your judgement or co-ordination and you should not drive or use machinery. Consult your doctor or pharmacist for more details.

When can I stop?

  • It is important to continue taking this medication even if you feel well, unless your doctor tells you to stop.


If any of these persist or you consider them severe then inform your doctor or pharmacist.

Tell your doctor immediately if you develop any of the following symptoms:

  • Rash or other allergic reactions such as itching, swollen lips or face or shortness of breath (if this happens stop taking fluoxetine immediately)
  • Skin turns red or starts to blister or peel
  • Unexplained fever with faster breathing or heart rate, stiff muscles or tremor and changes in your mental state such as confusion, irritability and feeling very agitated (these symptoms may be associated with the very rare serotonin or neuroleptic malignant syndrome)
  • Restlessness and unable to sit or stand still (akathisia)
  • Weakness, drowsiness or confusion (most common in elderly people and those taking water tablets also known as diuretics)
  • Long and painful erection of the penis
  • Feeling irritable and very agitated
  • Thoughts of suicide and worsening of depression or anxiety (this can be more common in younger patients, including children, than in older patients)

You may experience some side effects when you stop taking fluoxetine including:

These symptoms are generally mild and disappear within a few weeks. If you experience any of these symptoms when stopping fluoxetine tell your doctor.

Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

A serious allergic reaction to this drug is unlikely, but seek immediate medical attention if it occurs. Symptoms of a serious allergic reaction include: rash, itching/swelling (especially of the face/tongue/throat), dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

The Yellow Card Scheme allows you to report suspected side effects from any type of medicine (which includes vaccines, herbals and over the counter medicines) that you are taking. It is run by the medicines safety watchdog called the Medicines and Healthcare products Regulatory agency (MHRA). Please report any suspected side effect on the Yellow Card Scheme website.


Before taking fluoxetine, tell your doctor or pharmacist if you are allergic to it; or to other SSRIs; or if you have any other allergies.

This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: an allergy to fluoxetine or to any other ingredients contained in the medicine, are being treated for depression with mono-amine oxidase inhibitor (MAOIs) or have taken them within the last two weeks, are pregnant or breast feeding.

Before using this medication, tell your doctor or pharmacist your medical history, especially any of the following:

  • Liver disease
  • Kidney disease
  • Epilepsy or fits (seizures)
  • Mania (very high energy and mood)
  • Susceptibility to angle-closure glaucoma (increased pressure in the eye)
  • Diabetes
  • Heart disease
  • You are receiving electro-convulsive therapy (ECT)
  • History of bleeding problems or develop bruising or unusual bleeding

Before having surgery, tell your doctor or dentist that you are taking this medication.

Does alcohol intake affect this drug?

  • You should avoid alcohol whilst taking fluoxetine

The elderly. Extra care should be taken if the dose of fluoxetine is increased in the elderly.

Pregnancy and breast-feeding - please ensure you read the detailed information below


It is not recommended to use fluoxetine during pregnancy. Fluoxetine should be avoided particularly during the first and third trimester as well as just before giving birth as it can produce side effects in the newborn baby.

It is sensible to limit use of medication during pregnancy whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


Fluoxetine passes into breast milk and is not recommended for use in breastfeeding.

Ask your doctor or pharmacist if you have any doubts or questions about this.

It is sensible to limit use of medication during breastfeeding whenever possible. However, your doctor may decide that the benefits outweigh the risks in individual circumstances and after a careful assessment of your specific health situation.

If you have any doubts or concerns you are advised to discuss the medicine with your doctor or pharmacist.


Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with them first.

This drug should not be used with the following medications because very serious, possibly fatal interactions may occur:

  • Non-selective or reversible mono-amine oxidase inhibitor (MAOIs) or a MAOI type A drugs. Examples of MAOIs include moclobemide, phenelzine, tranylcypromine and isocarboxazid. Some type B MAOIs such as selegiline can be used with fluoxetine provided that your doctor monitors you carefully.

If you are currently using any of these medications, or have taken them up to 5 weeks ago, tell your doctor or pharmacist before starting fluoxetine.

Before using this medication, tell your doctor or pharmacist of all prescription and non-prescription/herbal products you may use, especially of:

Remember to tell your doctor that you have taken any of these medicines even if it was up to 5 weeks ago.

This information does not contain all possible interactions. Therefore, before using fluoxetine, tell your doctor or pharmacist of all the products you use.


Symptoms of an overdose include feeling and being sick, fits (seizures), heart problems, lung problems and changes in mental condition ranging from agitation to coma. If you take too many capsules, go to your nearest hospital emergency department (or casualty) or tell your doctor straight away. Take the pack of fluoxetine with you if you can.

If you think you, or someone you care for, might have accidentally taken more than the recommended dose of fluoxetine or intentional overdose is suspected, contact your local hospital, GP or if in England call 111. In Scotland call NHS 24. In Wales, call NHS Direct Wales. In the case of medical emergencies, always dial 999.


If you miss a dose, take your next dose the next day at the usual time. Do not double the dose to catch up.

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Source: Selected from data included with permission and copyrighted by Boots UK Limited. This copyrighted material is sourced from a licensed data provider and is not for distribution, except as may be authorised by the applicable terms of use.
CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgement of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse events, nor should it be construed to indicate that use of a particular medicine is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any medicine, changing any diet, or discontinuing any course of treatment.

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