How should I take fluoxetine?
Take fluoxetine exactly as prescribed by your doctor. Follow all directions on your prescription label. Your doctor may occasionally change your dose. Do not take this medicine in larger or smaller amounts or for longer than recommended.
Do not crush, chew, break, or open a delayed-release capsule. Swallow it whole.
Measure liquid medicine with the dosing syringe provided, or with a special dose-measuring spoon or medicine cup. If you do not have a dose-measuring device, ask your pharmacist for one.
To treat premenstrual dysphoric disorder, the usual dose of fluoxetine is once daily while you are having your period, or 14 days before you expect your period to start. Follow your doctor’s instructions.
It may take up to 4 weeks before your symptoms improve. Keep using the medication as directed and tell your doctor if your symptoms do not improve.
Do not stop using fluoxetine suddenly, or you could have unpleasant withdrawal symptoms. Ask your doctor how to safely stop using fluoxetine.
Store at room temperature away from moisture and heat.
What happens if I miss a dose?
Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.
If you miss a dose of Prozac Weekly, take the missed dose as soon as you remember and take the next dose 7 days later. However, if it is almost time for the next regularly scheduled weekly dose, skip the missed dose and take the next one as directed. Do not take extra medicine to make up the missed dose.
What happens if I overdose?
Seek emergency medical attention
What should I avoid while taking fluoxetine?
Drinking alcohol can increase certain side effects of fluoxetine.
Ask your doctor before taking a nonsteroidal anti-inflammatory drug (NSAID) for pain, arthritis, fever, or swelling. This includes aspirin, ibuprofen (Advil, Motrin), naproxen (Aleve), celecoxib (Celebrex), diclofenac, indomethacin, meloxicam, and others. Using an NSAID with fluoxetine may cause you to bruise or bleed easily. This medication may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert.
Fluoxetine side effects
Get emergency medical help if you have signs of an allergic reaction to fluoxetine: skin rash or hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Report any new or worsening symptoms to your doctor, such as: mood or behavior changes, anxiety, panic attacks, trouble sleeping, or if you feel impulsive, irritable, agitated, hostile, aggressive, restless, hyperactive (mentally or physically), more depressed, or have thoughts about suicide or hurting yourself.
Call your doctor at once if you have:
- blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights;
- signs of high levels of serotonin in the body–agitation, hallucinations, fever, fast heart rate, overactive reflexes, nausea, vomiting, diarrhea, loss of coordination, fainting;
- signs of low levels of sodium in the body–headache, confusion, slurred speech, severe weakness, vomiting, loss of coordination, feeling unsteady;
- very stiff (rigid) muscles, high fever, sweating, confusion, fast or uneven heartbeats, tremors, feeling like you might pass out; or
- severe skin reaction–fever, sore throat, swelling in your face or tongue, burning in your eyes, skin pain, followed by a red or purple skin rash that spreads (especially in the face or upper body) and causes blistering and peeling.
Common fluoxetine side effects may include:
- sleep problems (insomnia), strange dreams;
- headache, dizziness, vision changes;
- tremors or shaking, feeling anxious or nervous;
- pain, weakness, yawning, tired feeling;
- upset stomach, loss of appetite, nausea, vomiting, diarrhea;
- dry mouth, sweating, hot flashes;
- changes in weight or appetite;
- stuffy nose, sinus pain, sore throat, flu symptoms; or
- decreased sex drive, impotence, or difficulty having an orgasm.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.
What other drugs will affect fluoxetine?
Taking fluoxetine with other drugs that make you sleepy or slow your breathing can cause dangerous side effects or death. Ask your doctor before taking a sleeping pill, narcotic pain medicine, prescription cough medicine, a muscle relaxer, or medicine for anxiety, depression, or seizures.
Many drugs can interact with fluoxetine. Not all possible interactions are listed here. Tell your doctor about all your current medicines and any you start or stop using, especially:
- any other antidepressant;
- St. John’s Wort;
- tryptophan (sometimes called L-tryptophan);
- a blood thinner – warfarin, Coumadin, Jantoven;
- medicine to treat anxiety, mood disorders, thought disorders, or mental illness – amitriptyline, buspirone, desipramine, lithium, nortriptyline, and many others;
- medicine to treat ADHD or narcolepsy – Adderall, Concerta, Ritalin, Vyvanse, Zenzedi, and others;
- over-the-counter pain medications including ibuprofen, acetaminophen, aspirin, or similar medications;
- migraine headache medicine – rizatriptan, sumatriptan, zolmitriptan, and others; or
- narcotic pain medicine – fentanyl, tramadol.
This list is not complete and many other drugs can interact with fluoxetine. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Give a list of all your medicines to any healthcare provider who treats you.