What To Know About Prozac (Fluoxetine)

An SSRI Used For Depression Treatment

a woman taking medication

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Prozac (fluoxetine) is a type of medication used to treat depression and depressive symptoms. It belongs to a class of drugs called selective serotonin reuptake inhibitors (SSRI). SSRIs are also used to treat anxiety disorders including panic disorder, bulimia, obsessive-compulsive disorder, among other conditions.

Prozac is also available in a generic formulation called fluoxetine HCL. It is available as a capsule, delayed-release capsule, tablet, and a solution. 

Uses 

The FDA approves Prozac for several mental illnesses and it is use off-label for several conditions.

Major Depressive Disorder

Major depressive disorder (MDD) is a mood disorder characterized by persistent and severe feelings of sadness and despair accompanied by a variety of other emotional, physical, and behavioral changes.

Obsessive-Compulsive Disorder

Obsessive-compulsive disorder (OCD) is a condition, that occurs when a person experiences unwanted and recurrent thoughts. They typically also experience compulsions which are repetitive behaviors intended to help them deal with their obsessive thoughts.

Bulimia

Bulimia is an eating disorder characterized by excessive eating (binge) usually followed by extreme measures such as fasting or inducing vomit to prevent weight gain (purge). 

Panic Disorder

A person living with panic disorder will often experience sudden episodes of intense fear which they have no control over accompanied by a variety of physical and emotional symptoms. 

Treatment-Resistant Depression

Prozac in combination with Zyprexa (olanzapine) has an indication for treating treatment-resistant depression.

Acute Depressive Episodes Associated With Bipolar 1 Disorder

The same Prozac/Zyprexa combination also has an indication for people who have depressive episodes as a result of bipolar 1 disorder.

Premenstrual Dysphoric Disorder (PMDD)

Prozac is sometimes used to treat women who experience severe depressive symptoms just before their menstrual period begins.

Off-Label Uses

Even though they aren’t approved by the FDA , Prozac is sometimes used off-label to alleviate symptoms of the following conditions:

  • Borderline personality disorder 
  • Fibromyalgia
  • Generalized anxiety disorder (GAD)
  • Migraines
  • Premature ejaculation
  • Post-traumatic stress disorder 

Before Taking 

Before taking Prozac talk through the list of active and inactive ingredients with your doctor to ensure that you aren’t allergic to any ingredients in the medication.

Signs of an allergic reaction include rash, difficulty breathing and swelling of the face, tongue, or throat. If you suspect that you're having an allergic reaction, get medical help immediately. 

It’s a good rule of thumb to disclose to your doctor any other medication, vitamins, and supplements you might be taking to make sure that they don’t interact with the medication being prescribed to you.

If you have a history of any other medical conditions, especially liver disease, kidney disease, diabetes, and other mental health conditions you should also discuss this with your doctor.

Precautions and Contraindications 

Prozac is prescribed with caution to pregnant women. Women in their third trimester of pregnancy who are using Prozac may experience adverse effects in their babies when the baby is born.

If you become pregnant while already on Prozac disclose this to your doctor to figure out the next steps. If you are breastfeeding, discuss the risks and benefits of Prozac use with your doctor. 

You shouldn’t discontinue Prozac without consulting your doctor as this might worsen your symptoms or cause a relapse. If your doctor asks you to discontinue Prozac suddenly, you might experience withdrawal symptoms like nausea and insomnia, although given Prozac's long half-life, this is less common than with other antidepressants.

Dosage

Prozac is prescribed by a doctor who will recommend a dosage for your particular condition based on your medical history, tolerance to the drug, severity of your symptoms, and any other factors they might consider relevant.

However, the manufacturer of this medication typically recommends the following doses for these conditions. 

  • Major Depressive Disorder: The starting dose is usually 20 milligrams (mg) a day, typically taking in the morning. Your doctor might increase your doses if there are no significant improvements in your symptoms weeks after you start. 
  • Obsessive-Compulsive Disorder: Adults are typically advised to take 20 mg a day, taken in the morning to start, but it is often raised to 60 mg to 80 mg a day. 
  • Bulimia: 60 mg a day taken in the morning is the typical recommended dosage in the treatment of bulimia, although this will be started much lower and potentially titrated to this target dose.
  • Depressive Episodes Associated With Bipolar 1 Disorder: 20 mg of Prozac a day is recommended as an initial dose in combination with 5 mg of Zyprexa, although a combination pill of 25 mg of Prozac and 6 mg of Zyprexa may be used.  
  • Treatment-Resistant Depression: Similar dosing of Prozac and Zyprexa to the recommendations for depressive episodes associated with bipolar 1 disorder are often used.

Modifications

Children with major depressive disorder and obsessive-compulsive disorder are typically given an initial dose of 10 mg. Elderly people and people who have a hepatic impairment are also prescribed lower dosages.

While administering Prozac to pregnant women is avoided if possible, especially in their last trimester, your doctor might carefully weigh the pros and cons and decide to prescribe Prozac.

How to Take and Store 

Prozac can be taken with or without food. It should be stored at room temperature and kept away from direct sunlight. Don’t store this medication in your bathroom because bathrooms tend to be moist which is not an ideal environment for storage.

Take Prozac at the time recommended by your doctor, which in most cases is in the morning. If you are taking a delayed-release capsule, swallow it whole, don’t crush, chew or cut it before taking. 

Like with most SSRIs, it might take several weeks before you start seeing positive effects from Prozac. Don’t discontinue it even if you feel you aren’t getting better yet or if you feel you don’t need it anymore.

Side Effects

Prozamight cause some side effects, these effects typically go away with time. However, if you experience persistent, bothersome, or worsening side effects, you should tell your doctor about it. 

Common

Some common but mild side effects of using Prozac include: 

  • Anxiety 
  • Headaches 
  • Low libido 
  • Loss of appetite 
  • Dizziness 
  • Drowsiness 
  • Insomnia 
  • Weight changes 
  • Stuffy nose 
  • Dry mouth 

Some of these symptoms will pass shortly after you start using the medication. However, if you experience any new side effects or if any old side effects start to worsen, then you should report it to your medical doctor. 

Severe 

Some people might experience more severe side effects while using Prozac. In rare cases, Prozac could also cause a rare condition known as Serotonin syndrome, particularly if used in combination with other medications that impact serotonin.

This condition occurs when there’s excessive serotonin in your body, and can cause symptoms of fever, nausea, hallucinations, agitation, and coordination problems. If you suspect you are someone you know is showing signs of serotonin syndrome, contact your doctor immediately.

Less than 1 in 100 people experience severe side effects when using this medication.

Warnings and Interactions

If you are on any monoamine oxidase inhibitors (MAOI) like Marplan, you shouldn’t be taking Prozac. Prozac is typically not prescribed to people who have been taking am MAOI for at least 14 days. MAOIs are also typically not prescribed to people who have been on Prozac or who have stopped taking Prozac less than five weeks before their consultation.

People with major depressive disorder who are already prone to experiencing suicidal thoughts might sometimes experience the development of suicidal thoughts or a worsening of suicidal thoughts while taking Prozac.

It's important to watch out for any sudden or unusual changes in their behavior, especially during the first couple of months of use. Teenagers and young adults who are aged between 18 and 24 are particularly at risk. 

If you are having suicidal thoughts, contact the National Suicide Prevention Lifeline at 1-800-273-8255 for support and assistance from a trained counselor. If you or a loved one are in immediate danger, call 911.

For more mental health resources, see our National Helpline Database.

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Article Sources
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