In US fluoxetine clinical trials, 0.7% of 10,782 patients reported mania/hypomania see USE IN SPECIFIC POPULATIONS (8.4). Postmarketing cases of QT interval prolongation and ventricular arrhythmia including Torsades de Pointes have been reported in patients treated with fluoxetine. Fluoxetine should be used with caution in patients with congenital long QT syndrome; a previous history of QT prolongation; a family history of long QT syndrome or sudden cardiac death; and other conditions that predispose to QT prolongation and ventricular arrhythmia.

What should I tell my healthcare provider before taking fluoxetine? You should discuss all treatment choices with your healthcare provider. Keep all follow-up visits with your healthcare provider and call between visits if you are worried about symptoms.

• Fluoxetine doses above 60 mg/day have not been systematically evaluated in patients with Panic Disorder.
• Healthcare providers should instruct their patients to read the Medication Guide before starting therapy with fluoxetine tablets and to reread it each time the prescription is renewed.
• Fluoxetine hydrochloride oral tablets are not approved for use in pediatric patients.
• Advise breastfeeding women using Fluoxetine Tablets to monitor infants for agitation, irritability, poor feeding and poor weight gain and to seek medical care if they notice these signs see USE IN SPECIFIC POPULATIONS (8.2).
• Fluoxetine is extensively metabolized in the liver to norfluoxetine and a number of other unidentified metabolites.
• Because fluoxetine’s metabolism, like that of a number of other compounds including TCAs and other SSRIs, involves the CYP2D6 system, concomitant therapy with drugs also metabolized by this enzyme system (such as the TCAs) may lead to drug interactions see DRUG INTERACTIONS (7.6).

3 Allergic Reactions and Rash

Additionally, in vitro studies have shown ketoconazole, a potent inhibitor of CYP3A4 activity, to be at least 100 times more potent than fluoxetine or norfluoxetine as an inhibitor of the metabolism of several substrates for this enzyme, including astemizole, cisapride, and midazolam. These data indicate that fluoxetine’s extent of inhibition of CYP3A4 activity is not likely to be of clinical significance. Because fluoxetine is tightly bound to plasma proteins, adverse effects may result from displacement of protein-bound fluoxetine by other tightly bound drugs see CLINICAL PHARMACOLOGY (12.3). Symptoms of sexual dysfunction occasionally persist after discontinuation of fluoxetine treatment. The pupillary dilation that occurs following use of many antidepressant drugs including fluoxetine may trigger an angle closure attack in a patient with anatomically narrow angles who does not have a patent iridectomy.

Fluoxetine Interactions

In the US general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Whether these systemic reactions and rash have a common underlying cause or are due to different etiologies or pathogenic processes is not known. Furthermore, a specific fluoxetine: side effects, dosage, uses, and more underlying immunologic basis for these reactions has not been identified.

More about Prozac (fluoxetine)

This finding is from a prospective, longitudinal study that followed 201 pregnant women with a history of major depressive disorder who were euthymic and taking antidepressants at the beginning of pregnancy. Consider the risk of untreated depression when discontinuing or changing treatment with antidepressant medication during pregnancy and postpartum. Because of the long elimination half-lives of the parent drug and its major active metabolite, changes in dose will not be fully reflected in plasma for several weeks, affecting both strategies for titration to final dose and withdrawal from treatment. This is of potential consequence when drug discontinuation is required or when drugs are prescribed that might interact with fluoxetine and norfluoxetine following the discontinuation of fluoxetine see CLINICAL PHARMACOLOGY (12.3).

Does Fluoxetine interact with my other drugs?

There was considerable variation in risk of suicidality among drugs, but a tendency toward an increase in the younger patients for almost all drugs studied. There were differences in absolute risk of suicidality across the different indications, with the highest incidence in MDD. The risk differences (drug versus placebo), however, were relatively stable within age strata and across indications.

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• There were differences in absolute risk of suicidality across the different indications, with the highest incidence in MDD.
• This influence may persist for 3 weeks or longer after fluoxetine is discontinued.
• Patients in the 16-week study received a fixed fluoxetine dose of 60 mg/day (once a day) or placebo.
• Some young people have thoughts about suicide when first taking an antidepressant.
• The size of the effect was related to baseline frequency, with greater reductions seen in patients with higher baseline frequencies.
• Prescriptions for fluoxetine should be written for the smallest quantity of tablets consistent with good patient management, in order to reduce the risk of overdose.

Serotonin syndrome is a potentially life-threatening condition caused by an excess of serotonin in the body, usually triggered by medications or drugs that increase serotonin activity. It most commonly occurs when certain antidepressants, migraine medications, opioids, or illicit drugs are taken alone in high doses or, more often, in combination. Common drug classes that can cause serotonin syndrome include selective serotonin reuptake inhibitors (SSRIs), monoamine oxidase inhibitors (MAOIs), and opioids like tramadol. Serotonin release by platelets plays an important role in hemostasis. Altered anticoagulant effects, including increased bleeding, have been reported when SNRIs or SSRIs are co-administered with warfarin.

Fluoxetine hydrochloride oral tablets are not approved for use in pediatric patients. Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use fluoxetine only for the indication prescribed. 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. Follow all directions on your prescription label and read all medication guides or instruction sheets. You should not use fluoxetine if you also take pimozide or thioridazine, or if you are being treated with methylene blue injection.

Make sure you know how you react to fluoxetine before you drive, use machines, or do anything else that could be dangerous if you are not alert and well able to control your movements. The use of alcohol is not recommended in patients who are taking fluoxetine. Contact your doctor right away if you have dizziness, fainting, or a fast, pounding, or uneven heartbeat. Make sure your doctor knows if you have ever had a heart rhythm problem, including QT prolongation, or if you or a family member has had a heart attack, heart failure, low blood pressure, or a stroke. Closely monitor patients of all ages for clinical worsening and emergence of suicidal thoughts and behaviors.

Steady-state levels after prolonged dosing are similar to levels seen at 4 to 5 weeks. Fluoxetine can increase the level of pimozide through inhibition of CYP2D6. Clinical studies of pimozide with other antidepressants demonstrate an increase in drug interaction or QT prolongation.

In patients with diabetes, fluoxetine may alter glycemic control. Hypoglycemia has occurred during therapy with fluoxetine, and hyperglycemia has developed following discontinuation of the drug. As is true with many other types of medication when taken concurrently by patients with diabetes, insulin and/or oral hypoglycemic, dosage may need to be adjusted when therapy with fluoxetine is instituted or discontinued.