Fluoxetine hydrochloride (
Prozac®) is a prescription medicine used to treat a number of conditions within the brain.
Fluoxetine is manufactured by Eli Lilly and Company.
Generic fluoxetine is made by several manufacturers.
Fluoxetine is licensed to treat a number of conditions.
These uses include the treatment of:
When used in combination with
Zyprexa® (
olanzapine), fluoxetine is approved for the following uses:
- Depression associated with bipolar disorder
- Treatment-resistant depression (depression that has not responded to treatment with at least two different antidepressants).
Sarafem® (a brand-name medication that contains the exact same medication as fluoxetine) is also licensed to treat premenstrual dysphoric disorder (PMDD), but Prozac (and
generic Prozac) are not approved for this use.
Fluoxetine is part of a class of drugs called selective serotonin reuptake inhibitors, or
SSRIs for short. SSRIs, such as fluoxetine, act on a specific chemical within the brain known as serotonin. Serotonin is one of several chemicals used to send messages from one nerve cell to another.
As a message travels down a nerve, it causes the end of the cell to release serotonin. The serotonin enters the gap between the first nerve cell and the one next to it. When enough serotonin reaches the second nerve cell, it activates receptors on the cell and the message continues on its way. The first cell then quickly absorbs any serotonin that remains in the gap between cells. This is called "reuptake."
Normally, this process works without any problems. When the levels of serotonin become unbalanced, however, it can cause a variety of conditions, including
depression. Fluoxetine helps to block the reuptake of serotonin so more serotonin remains in the space between the brain's nerve cells. This gives the serotonin a better chance of activating the receptors on the next nerve cell.
There have been several studies looking at the effects of fluoxetine on a variety of conditions.
Fluoxetine for Depression
Studies have shown the drug to be effective for
depression treatment in children, teens, and adults. These studies included children as young as eight years old. Another study showed that a long-acting form (
Prozac Weekly) was also effective for treating depression in adults.
Fluoxetine for OCD
In studies, 28 percent of people with
obsessive-compulsive disorder (
OCD) who took fluoxetine felt their OCD was "much improved," compared to only 8 percent of those who were not taking it. None of the people taking the medication felt that their OCD was worse, compared to 8 percent of people not on fluoxetine. In other studies, it was also shown to be effective for OCD in children and teens.
Fluoxetine for Bulimia
Studies have shown it to be effective for treating
bulimia in adults. While the
antidepressant effects of fluoxetine may take longer to be seen, the effects of fluoxetine for treating bulimia were seen within one week. Also, it helped people with bulimia regardless of whether they had
depression or not. It has not been studied in children or teens with bulimia.
Fluoxetine for Panic Disorder
Two studies looked at using fluoxetine to treat adults with
panic disorder. Up to 62 percent of people taking it were free from
panic attacks, compared to only 44 percent of those not taking the medicine. It has not been studied in children or teens with panic disorder.
When and How to Take Fluoxetine
Some general considerations for when and how to take this drug include:
- Fluoxetine comes in capsule and liquid form. It is taken by mouth, usually once or twice a day.
- A long-acting form is also available (Prozac Weekly). Prozac Weekly is taken by mouth once a week. Make sure to swallow the capsules whole (do not open, chew, or crush the capsules).
- If fluoxetine makes you drowsy, try taking it before bedtime. If it causes insomnia for you, try taking it in the morning.
- You can take the medication with or without food. If it bothers your stomach, try taking it with food.
- It should be taken at the same time(s) each day (or with Prozac Weekly, the same day each week) to maintain an even level of the drug in your blood.
- For the antidepressant to work properly, it must be taken as prescribed. It will not work if you stop taking it.
The dose that your healthcare provider recommends will vary depending on a number of factors, including:
- Your age
- The medical condition being treated
- Other medical conditions you may have
- Other medications you may currently be taking.
As is always the case, do not adjust your fluoxetine dose unless your healthcare provider specifically instructs you to do so.
As with any medicine, there are possible side effects. However, not everyone who takes the
antidepressant will experience side effects. In fact, most people tolerate it well. When fluoxetine side effects do occur, in most cases they are minor and either require no treatment or can easily be treated by you or your healthcare provider. Serious side effects are less common.
The most common side effects include:
(Click Fluoxetine Side Effects to learn about the specific side effects of this medication, including serious side effects to look out for.)
You can also read about possible side effects by clicking on the following links:
Fluoxetine can potentially interact with a number of medicines.
What Should I Tell My Healthcare Provider?
You should talk with your healthcare provider prior to taking fluoxetine if you have:
Also, let your healthcare provider know if you are:
Tell your healthcare provider about all other medicines you may be taking, including prescription and non-prescription medicines, vitamins, and herbal supplements.
Alternatives to Fluoxetine
Depression, even in its most severe form, is highly treatable. As with many illnesses, getting
depression treatment early is more effective and reduces the chance of recurrence.
The most common forms of treatment for depression are medication (
antidepressants) and psychotherapy ("talk therapy"). In some cases of severe depression, healthcare providers may recommend electroconvulsive therapy (ECT). Some people may also try complementary or alternative treatments for depression
(see Natural Remedies for Depression).
For most people, fluoxetine is quite effective in treating depression. It is also generally well-tolerated. However,
fluoxetine side effects can occur or the medicine may not work as well as needed. In these cases, your healthcare provider may recommend an alternative to fluoxetine. Some examples of substitute depression medications include:
People who take too much fluoxetine may have overdose symptoms that could include:
If you happen to overdose on fluoxetine, seek medical attention immediately.
Fluoxetine should be stored at room temperature, away from moisture or heat. It should be kept in an airtight container.
Keep fluoxetine and all medications out of the reach of children.
What Should I Do If I Miss a Dose?
If you do not take your fluoxetine as scheduled, take your missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and continue with your regular schedule. Do not take a double dose of fluoxetine.
Fluoxetine capsules are available in four strengths:
- Fluoxetine 10 mg capsules
- Fluoxetine 20 mg capsules
- Fluoxetine 40 mg capsules
- Prozac Weekly 90 mg capsules.
The liquid form of fluoxetine is available in one strength: fluoxetine oral solution 20 mg per 5 mL (20 mg per teaspoonful). Although brand-name fluoxetine tablets are no longer being made, generic fluoxetine tablets are still available.
There are currently both brand-name and generic fluoxetine and fluoxetine liquid licensed for sale. However,
generic Prozac Weekly is not available as a generic at this time.
