Prozac is an antidepressant that has been demonstrated to work well as treatment for several types of anxiety disorders. It’s FDA approved for obsessive-compulsive disorder (OCD) and panic disorder. It’s also prescribed off-label for social anxiety and post-traumatic stress disorder (PTSD). There are some risks, possible side effects, and certain medications to avoid if you’re taking Prozac.
What Is Prozac?
Although Prozac (fluoxetine) is typically a medication for depression, it’s also used as a medication for anxiety disorders, OCD, and panic disorder. It’s in a class of medications known as selective serotonin reuptake inhibitors (SSRIs). It affects the level of the neurotransmitter serotonin, which naturally exists in the brain. It has been safely used with adults, seniors, and children ages 8 and older.1
Prozac can, however, create problems during pregnancy and after the birth, and is generally not advised for use in late term pregnancy.
Does Prozac Help With Anxiety Disorders?
Prozac doesn’t cure these disorders, but it can help reduce specific anxiety symptoms. For OCD, it is approved to treat obsessions and compulsions. Along with other SSRI medications, Prozac has the benefit of not being habit-forming, so it can be used long term to treat anxiety disorders. It is usually taken once daily, and there is a generic option available.
Types of anxiety disorders Prozac is approved to treat include:
- Prozac for OCD: Prozac is approved by the FDA for the relief of symptoms of OCD. It has been moderately effective in reducing repetitive or ritualized behaviors and obsessive thoughts.2
- Prozac for Panic Attacks: Prozac is approved by the FDA for the treatment of panic attacks and can help treat panic disorders. It has been effective in reducing the occurrence of sudden attacks of extreme fear and worries about having these attacks.3
Prozac is also used off-label to treat other anxiety disorders. Off-label treatment is when a medication is prescribed by a physician for a reason other than it is approved for.
Anxiety disorders that Prozac is used to treat off-label include:
- Prozac for Social Anxiety: Prozac is used off-label for relief of symptoms of social anxiety. It helps reduce anxiety and increase feelings of relaxation and focus.
- Prozac for PTSD: Prozac is used off-label in the treatment of PTSD. It has been known to improve sleep and help the person return to their normal activities without feeling the need to avoid places or situations.4
How Does Prozac Help With Anxiety Disorders?
Prozac is one of several medications known as SSRIs. Serotonin is one of the neurotransmitters that normally carry signals between neurons. The SSRIs block the reabsorption (reuptake) of serotonin into the neurons, leaving more serotonin available to enable messages to travel between neurons.5 Increased levels of serotonin have been associated with an overall calming of the nervous system, improved mood, and better sleep quality.6
Another way the SSRIs help is through their effect on the brain’s structure over a period of time. Higher levels of serotonin are believed to increase the brain’s ability to restructure parts of itself, in effect, becoming more adaptable. After weeks of use of an SSRI, the brain becomes more able to adapt to new learning.7
How to Take Prozac
Prozac contains the active medication fluoxetine and is available in a variety of forms: tablet, capsule, extended release capsule, and liquid solution.8 It is usually taken only once daily, in the morning. As for any prescription medication, it should be taken according to the instructions of a physician. You should not stop taking Prozac except under the advice and guidance of your physician. Stopping suddenly can cause unpleasant withdrawal symptoms.
Prozac Dosage For Anxiety Disorders
The effective dosage of Prozac varies with age, disorder, and individual response. You should always consult with your doctor about dosage before taking Prozac, and should never adjust dosage without consulting your physician first.
Obsessive-Compulsive Disorder
Adults with OCD are started at 20 mg per day, with gradual increase as needed based on symptoms. The typical range for adults with OCD is between 20 to 60 mg per day. Your doctor will work with you on your dosage and you should only take the amount of Prozac your doctor has instructed you to take.
Children and teens with OCD are started at 10 mg per day for 2 weeks then have their dose increased to 20 mg per day. The typical range for children with OCD is between 20 and 60 mg per day.9
Panic Disorder
For both adults and children/teens with panic disorder, the starting dose is 10 mg per day for 1 week. Then the dose is increased to 20 mg per day. If needed, the dosage can continue to be increased up to 60 mg per day. Your doctor will work with you on your dosage and you should only take the amount of Prozac your doctor has instructed you to take.
Can You Overdose On Prozac?
It is possible to overdose on Prozac, which can cause dangerous and possibly life-threatening symptoms. In the event of an overdose, call 9-1-1 for emergency assistance. Consider also calling your doctor as soon as possible. Depending on the severity of your symptoms, it might be necessary to go to an emergency room.
Possible symptoms of a Prozac overdose include:10
- Agitation, confusion, or nervousness
- Dizziness
- High blood pressure or fast heart rate
- Poor coordination or trouble walking
- Seizures, possibly delayed onset
- Gastrointestinal symptoms such as nausea or vomiting
- Tremors
How Quickly Does Prozac Work For Anxiety Disorders?
For most people, it takes at least 2 weeks after starting Prozac to begin to feel better. Symptoms such as better sleep, energy level, and appetite are usually the first signs of improvement. It may take 6 to 8 weeks to experience the full benefit of Prozac.6 Since it is an SSRI, the time required can be compared to how long it takes for antidepressants to work.
Side Effects of Prozac
As for any medication, there are numerous possible side effects of taking Prozac. However, many people have minimal side effects or none at all. Most of the common side effects of Prozac will improve over the first 2 weeks of taking the medication. The sexual side effects usually do not lessen over time.
Common Prozac side effects include:11
- Headache
- Nausea
- Diarrhea
- Dry mouth
- Increased sweating
- Feeling nervous
- Restlessness
- Fatigue
- Difficulty sleeping
- Problems with orgasm, ejaculatory delay, or loss of libido
More serious side effects may also occur when taking Prozac. A doctor should be notified immediately in these circumstances.
Serious fluoxetine side effects that need immediate attention include:6
- Mood shifts, very high energy, agitation
- Thoughts or behaviors of suicide*
- Unusual bruising or bleeding
- Muscle weakness or spasm
- Unusual weight loss
- Shaking or tremors
There are some additional rare but serious possible side effects of taking Prozac. A doctor should be notified immediately if any of these symptoms occur. You may also need to seek emergency care with the onset of any of these symptoms.
Rare and serious side effects of Prozac may include:6
- Seizures
- Kidney problems, possibly seen as changes in urination
- Eye pain, swelling, or redness
- Changes in vision, blurred vision
- Serotonin syndrome, particularly if other drugs that increase serotonin are being taken along with fluoxetine
- Allergic reactions, such as rash, itching, or trouble breathing
Medications to Avoid if You’re Taking Prozac
It’s important to discuss the use of any other drugs with your doctor before starting Prozac. There are numerous medications that might interact, resulting in possibly serious side effects. Some of the more commonly used medications that might interact include: aspirin, non-steroidal anti-inflammatory drugs (NSAIDs), warfarin, and other blood thinners. Use of these drugs while taking fluoxetine increases the risk of bleeding.5
Prozac might also interact with other antidepressants, amphetamines, pain medications, or St. John’s Wort, presenting the risk of serotonin syndrome.,11
Symptoms of serotonin syndrome include:
- Anxiety
- Agitation
- Fever
- Sweating
- Confusion
- Tremors
- Restlessness
- Poor coordination
- Large changes in blood pressure
- Rapid heart rate
You should talk with your doctor before starting any prescription medication, over-the-counter medication, herb, or supplement while taking Prozac.
Risks & Precautions of Taking Prozac
Note that drinking alcohol or using illegal drugs might decrease the benefits or increase the adverse effects of Prozac, such as sedation.11 There are also several risks associated with taking Prozac and other anxiety medication during pregnancy, or during the course of breastfeeding.11 The risks and benefits of using an antidepressant at these times should be discussed with your doctor, as well as the alternative ways to manage anxiety while pregnant.
It’s very important not to abruptly stop taking Prozac due to the risk of prozac withdrawal. Stopping suddenly can result in one or more withdrawal symptoms, including: nausea, dizziness, vomiting, irritability, headache, nightmares, or prickling/tingling sensation on the skin.11 Talk with your doctor if you are considering discontinuing Prozac.
The FDA has placed a black box warning for the use of antidepressants. Studies have shown an increased risk of suicidal thoughts and behaviors among children, teens, and adults under age 24 while using antidepressants. To manage this risk, families and caregivers should remain alert to signs of increased anxiety, restlessness, irritability, aggressiveness, or insomnia.
If any of these changes are noticed, they should be reported to the health-care professional immediately. This risk is especially high during the first few months of treatment, or when the dosage is changed.11
Questions to Ask Your Doctor About Taking Prozac For Anxiety Disorders
If you’re considering taking Prozac for an anxiety disorder, have a thorough discussion with your health care team. The physician or psychiatrist who is prescribing it will need to assess your possible benefits and risks of using this medication. You shouldn’t feel uncomfortable asking questions or addressing concerns.
Here are questions to ask your care team about Prozac:12
- How well might Prozac work to relieve my symptoms?
- What are the benefits of fluoxetine (Prozac)?
- What side effects should I watch for?
- What is my risk for serious side effects, given my medical history and health condition?
- What lifestyle changes would I need to make if I started taking this medication? For example, do I need to give up alcohol or any other drug that I am currently using?
- What is the cost for this medication? Are there any less costly but equally effective alternatives?
- How might the medication interact with what I am taking now? Tell your team about other medicines, vitamins, or supplements.
- Would I benefit more if I participate in psychotherapy while taking Prozac (fluoxetine)?
- If I cannot tolerate side effects, how would I stop taking Prozac?
- Are there other SSRIs or other types of medication that might be better for me?
Final Thoughts
Prozac for anxiety disorders can be effective, especially when combined with psychotherapy. As with other medications, there are possible side effects to be considered as well as certain risks and precautions. Before taking fluoxetine for an anxiety disorder, discuss a treatment plan with your doctor and care team to see if it’s the right option for you.
For Further Reading
- Anxiety & Depression Association of American (ADAA) online support group
- The Tribe: Peer to peer online support groups
- Daily Strength: Anxiety support group
- Mayo Clinic
Prozac for Anxiety Infographics
