Fenfluramine is a prescription medicine. The sections below reproduce one FDA label for it, named under "Label". Products in other forms, strengths or from other makers have their own labels, which can differ.
- Type
- Prescription only (Rx)
- Brand names
- Fintepla
- Taken
- Oral
- Label
- UCB, Inc., revised October 27, 2025 · full label on DailyMed
- Generic
- FDA-approved (1 company) · details
Boxed warning — the FDA's most serious warning for a medicine
WARNING: VALVULAR HEART DISEASE and PULMONARY ARTERIAL HYPERTENSION FINTEPLA can cause valvular heart disease and pulmonary arterial hypertension [see Warnings and Precautions (5.1) ]. Echocardiogram assessments are required before, during, and after treatment with FINTEPLA. The benefits versus the risks of initiating or continuing FINTEPLA must be considered, based on echocardiogram findings [see Dosage and Administration (2.1 , 2.6 ) and Warnings and Precautions (5.1) ]. Because of the risks of valvular heart disease and pulmonary arterial hypertension, FINTEPLA is available only through a restricted program under a Risk Evaluation and Mitigation Strategy (REMS) called the FINTEPLA REMS [see Warnings and Precautions (5.2) ]. WARNING: VALVULAR HEART DISEASE and PULMONARY ARTERIAL HYPERTENSION See full prescribing information for complete boxed warning. FINTEPLA can cause valvular heart disease and pulmonary arterial hypertension. ( 5.1 ) Echocardiogram assessments are required before, during, and after treatment with FINTEPLA. ( 2.1 , 2.6 , 5.1 ) FINTEPLA is available only through a restricted program called the FINTEPLA REMS. ( 5.2 )
What it is used for
FINTEPLA is indicated for the treatment of seizures associated with Dravet syndrome (DS) and Lennox-Gastaut syndrome (LGS) in patients 2 years of age and older. FINTEPLA is indicated for the treatment of seizures associated with Dravet syndrome and Lennox-Gastaut syndrome in patients 2 years of age and older. ( 1 )
Forms and strengths
Oral solution: 2.2 mg/mL fenfluramine as a clear, colorless, cherry flavored liquid. Oral solution: 2.2 mg/mL fenfluramine ( 3 )
Who should not take it (contraindications)
FINTEPLA is contraindicated in patients with: Hypersensitivity to fenfluramine or any of the excipients in FINTEPLA [see Description (11) ] Concomitant use, or within 14 days of the administration, of monoamine oxidase inhibitors because of an increased risk of serotonin syndrome [see Warnings and Precautions (5.7) ] Hypersensitivity to fenfluramine or any of the excipients in FINTEPLA ( 4 ) Within 14 days of the administration of monoamine oxidase inhibitors due to an increased risk of serotonin syndrome ( 4 )
Warnings and precautions
Decreased Appetite and Decreased Weight: Advise patients that FINTEPLA can cause decreased appetite and decreased weight. ( 5.3 ) Somnolence, Sedation, and Lethargy: Monitor for somnolence and sedation. Advise patients not to drive or operate machinery until they have gained sufficient experience on FINTEPLA. ( 5.4 ) Suicidal Behavior and Ideation: Monitor patients for suicidal behavior and thoughts. ( 5.5 ) Withdrawal of Antiepileptic Drugs: FINTEPLA should be gradually withdrawn to minimize the risk of increased seizure frequency and status epilepticus. ( 5.6 ) Serotonin Syndrome: Advise patients that serotonin syndrome is a potentially life-threatening condition and may occur with FINTEPLA, particularly with concomitant administration of FINTEPLA with other serotonergic drugs. ( 5.7 ) Increase in Blood Pressure: Monitor blood pressure during treatment. ( 5.8 ) Glaucoma: Discontinue therapy in patients with acute decrease in visual acuity or ocular pain. ( 5.9 )
5.1 Valvular Heart Disease and Pulmonary Arterial Hypertension FINTEPLA can cause valvular heart disease (VHD) and pulmonary arterial hypertension (PAH). There is a known association between serotonergic drugs with 5-HT2B receptor agonist activity, including fenfluramine (the active ingredient in FINTEPLA), and valvular heart disease and pulmonary arterial hypertension. Although no patients receiving FINTEPLA developed valvular heart disease or pulmonary arterial hypertension in clinical trials for DS and LGS of up to 3 years in duration, cases of valvular heart disease and pulmonary arterial hypertension have been reported during use of FINTEPLA in the postmarketing setting [see Boxed Warning and Adverse Reactions (6.1) ] . Because of this risk, cardiac monitoring is required prior to starting treatment, during treatment, and after treatment with FINTEPLA concludes . Cardiac monitoring via echocardiogram can identify evidence of valvular heart disease and pulmonary arterial hypertension prior to a patient becoming symptomatic, aiding in early detection of these conditions. Monitoring Prior to starting treatment, patients must undergo an echocardiogram to evaluate for valvular heart disease and pulmonary arterial hypertension. Echocardiograms should be repeated every 6 months, and once 3-6 months post-treatment with FINTEPLA. The prescriber must consider the benefits versus the risks of initiating or continuing treatment with FINTEPLA if any of the following signs are observed via ECHO: Valvular abnormality or new abnormality via echocardiogram. VHD as indicated by mild or greater aortic regurgitation or moderate or greater mitral regurgitation, with additional characteristics of VHD (e.g., valve thickening or restrictive valve motion). PAH as indicated by elevated right heart/pulmonary artery pressure (PASP > 35 mm Hg). FINTEPLA is available only through a restricted program under a REMS [see Warnings and Precautions (5.2) ]. 5.2 FINTEPLA REMS Program FINTEPLA is available only through a restricted distribution program called the FINTEPLA REMS program because of the risk of valvular heart disease and pulmonary arterial hypertension [see Warnings and Precautions (5.1) ]. Notable requirements of the FINTEPLA REMS Program include: Prescribers must be certified by enrolling in the FINTEPLA REMS program. Prescribers must counsel patients receiving FINTEPLA about the risk of valvular heart disease and pulmonary arterial hypertension, how to recognize signs and symptoms of valvular heart disease and pulmonary arterial hypertension, the need for baseline (pretreatment) and periodic cardiac monitoring via echocardiogram during FINTEPLA treatment, and cardiac monitoring after FINTEPLA treatment. Patients must enroll in the REMS program and comply with ongoing monitoring requirements [see Warnings and Precautions (5.1) ]. The pharmacy must be certified by enrolling in the REMS program and must only dispense to patients who are authorized to receive FINTEPLA. Wholesalers and distributors must only distribute to certified pharmacies. Further information is available at www.FinteplaREMS.com or by telephone at 1-877-964-3649.
5.3 Decreased Appetite and Decreased Weight FINTEPLA can cause decreases in appetite and weight. In placebo-controlled studies for DS (Study 1 and Study 2 combined), approximately 37% of patients treated with FINTEPLA reported, as an adverse reaction, decreased appetite and approximately 9% reported decreased weight, as compared to 8% and 1%, respectively, of patients on placebo . In the placebo- controlled study for LGS (Study 3), approximately 28% of patients treated with FINTEPLA reported, as an adverse reaction, decreased appetite and approximately 5% reported decreased weight, as compared to 15% and 2%, respectively, of patients on placebo [see Adverse Reactions (6.1) ] . By the end of the controlled studies, 19% (Studies 1 and 2 combined) of DS patients and 7% (Study 3) of LGS patients treated with FINTEPLA had a measured decrease in weight of 7% or greater from their baseline weight, compared to 2% (Study 1 and 2) and 0% (Study 3) of patients on placebo. This measured decrease in weight appeared to be dose-related. In the controlled studies for DS, 26% of patients on FINTEPLA 0.7 mg/kg/day (Study 1), 19% of patients on FINTEPLA 0.4 mg/kg/day in combination with stiripentol (Study 2), and 13% of patients taking FINTEPLA 0.2 mg/kg/day (Study 1) experienced at least a 7% decrease in weight from baseline. In the controlled study for LGS, 9% of patients on FINTEPLA 0.7 mg/kg/day (Study 3) and 6% of patients on FINTEPLA 0.2 mg/kg/day (Study 3) experienced at least a 7% decrease in weight from baseline. Approximately half of the patients with LGS and most patients with DS resumed the expected measured increases in weight during the open-label extension studies. Given the frequency of these adverse reactions, the growth of pediatric patients treated with FINTEPLA should be carefully monitored. Weight should be monitored regularly during treatment with FINTEPLA, and dose modifications should be considered if a decrease in weight is observed.
5.4 Somnolence, Sedation, and Lethargy FINTEPLA can cause somnolence, sedation, and lethargy. In controlled studies for DS (Study 1 and Study 2 combined), the incidence of somnolence, sedation, and lethargy was 25% in patients treated with FINTEPLA, compared with 11% of patients on placebo. In the controlled study for LGS (Study 3), the incidence of somnolence, sedation, and lethargy was 19% in patients treated with FINTEPLA, compared with 16% of patients on placebo. In general, these effects may diminish with continued treatment [see Adverse Reactions (6.1) ]. Other central nervous system (CNS) depressants, including alcohol, could potentiate these effects of FINTEPLA. Prescribers should monitor patients for somnolence and sedation and should advise patients not to drive or operate machinery until they have gained sufficient experience on FINTEPLA to gauge whether it adversely affects their ability to drive or operate machinery.
5.5 Suicidal Behavior and Ideation Antiepileptic drugs (AEDs), including FINTEPLA, increase the risk of suicidal thoughts or behavior in patients taking these drugs for any indication. Patients treated with an AED for any indication should be monitored for the emergence or worsening of depression, suicidal thoughts or behavior, or any unusual changes in mood or behavior. Pooled analyses of 199 placebo-controlled clinical trials (mono- and adjunctive therapy) of 11 different AEDs that did not include FINTEPLA showed that patients randomized to one of the AEDs had approximately twice the risk (adjusted Relative Risk 1.8, 95% CI:1.2, 2.7) of suicidal thinking or behavior compared to patients randomized to placebo. […]
Side effects (adverse reactions)
The following clinically significant adverse reactions are described elsewhere in labeling: Valvular Heart Disease and Pulmonary Arterial Hypertension [see Warnings and Precautions (5.1) ] Decreased Appetite and Decreased Weight [see Warnings and Precautions (5.3) ] Somnolence, Sedation, and Lethargy [see Warnings and Precautions (5.4) ] Suicidal Behavior and Ideation [see Warnings and Precautions (5.5) ] Withdrawal of Antiepileptic Drugs [see Warnings and Precautions (5.6) ] Serotonin Syndrome [see Warnings and Precautions (5.7) ] Increase in Blood Pressure [see Warnings and Precautions (5.8) ] Glaucoma [see Warnings and Precautions (5.9) ] The most common adverse reactions (incidence at least 10% and greater than placebo) in patients with Dravet syndrome were decreased appetite; somnolence, sedation, lethargy; diarrhea; constipation; abnormal echocardiogram; fatigue, malaise, asthenia; ataxia, balance disorder, gait disturbance; blood pressure increased; drooling, salivary hypersecretion; pyrexia; upper respiratory tract infection; vomiting; decreased weight; fall; status epilepticus. ( 6.1 ) The most common adverse reactions (incidence at least 10% and greater than placebo) in patients with Lennox-Gastaut syndrome were diarrhea; decreased appetite; fatigue; somnolence; vomiting. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact UCB, Inc. at 1-844-599-2273 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.
6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. In controlled and uncontrolled trials in patients with Dravet syndrome (DS), 341 patients were treated with FINTEPLA, including 312 patients treated for more than 6 months, 284 patients treated for more than 1 year, and 138 patients treated for more than 2 years. In controlled and uncontrolled trials in patients with Lennox-Gastaut syndrome (LGS), 262 patients were treated with FINTEPLA, including 219 patients treated for more than 6 months, 172 patients treated for more than 1 year, and 127 patients treated for more than 2 years. Dravet Syndrome In placebo-controlled trials of patients with DS taking concomitant standard of care AEDs, 122 patients were treated with FINTEPLA and 84 patients received placebo [see Clinical Studies (14.1) ] . The duration of treatment in these trials was 16 weeks (Study 1) or 17 weeks (Study 2). In Study 1 and Study 2, the mean age was 9 years (range 2 to 19 years) and approximately 46% of patients were female and 74% were White. All patients were receiving at least one other AED. In Study 1 and Study 2, the rates of discontinuation as a result of any adverse reaction were 13%, 0%, and 7% for patients treated with FINTEPLA 0.7 mg/kg/day, 0.2 mg/kg/day, and 0.4 mg/kg/day in combination with stiripentol, respectively, compared to 6% for patients on placebo. The most frequent adverse reaction leading to discontinuation in the patients treated with any dose of FINTEPLA was somnolence (3%). The most common adverse reactions that occurred in patients treated with FINTEPLA (incidence at least 10% and greater than placebo) were decreased appetite; somnolence, sedation, lethargy; diarrhea; constipation; abnormal echocardiogram; fatigue, malaise, asthenia; ataxia, balance disorder, gait disturbance; blood pressure increased; drooling, salivary hypersecretion; pyrexia; upper respiratory tract infection; vomiting; decreased weight; fall; status epilepticus. Table 4 lists the adverse reactions that were reported in 5% or more of patients treated with FINTEPLA and at a rate greater than those on placebo during the titration and maintenance phases of Study 1 and Study 2. Table 4: Adverse Reactions in 5% or More of Patients Treated with FINTEPLA and Greater Than Placebo in Placebo-Controlled Trials for Dravet Syndrome (Study 1 and 2) Adverse Reaction FINTEPLA Dose Group Combined Placebo Group Patients in placebo groups from Studies 1 and 2 were pooled. Study 1 Study 2 0.2 mg/kg/day 0.7 mg/kg/day 0.4 mg/kg/day 0.4 mg/kg/day was not an intermediate dose. Patients on the 0.4 mg/kg/day dose were also taking concomitant stiripentol plus clobazam, which increases exposure of FINTEPLA. N=39 % N=40 % N=43 % N=84 % Decreased appetite 23 38 49 8 Somnolence, sedation, lethargy 26 25 23 11 Abnormal echocardiogram Consisted of trace and mild mitral regurgitation, and trace aortic regurgitation, which are considered physiologic. 18 23 9 6 Diarrhea 31 15 23 6 Constipation 3 10 7 0 Fatigue, malaise, asthenia 15 10 30 5 Ataxia, balance disorder, gait disturbance 10 10 7 1 Abnormal behavior 0 8 9 0 Blood pressure increased 13 8 0 5 Drooling, salivary hypersecretion 13 8 2 0 Hypotonia 0 8 0 0 Rash 8 8 5 4 Blood prolactin increased 0 5 0 0 Chills 0 5 2 0 Decreased activity 0 5 0 1 Dehydration 0 5 0 0 Insomnia 0 5 5 2 Pyrexia 15 5 21 14 Stereotypy 0 5 0 0 Upper respiratory tract infection 21 5 7 10 Vomiting 10 5 5 8 Weight decreased 13 5 7 1 Croup 5 3 0 1 Ear infection 8 3 9 5 Gastroenteritis 8 3 2 0 Increased heart rate 5 3 0 2 Irritability 0 3 9 2 Rhinitis 8 3 7 2 Tremor 3 3 9 0 Urinary incontinence 5 3 0 0 Decreased blood glucose 0 0 9 1 Bronchitis 3 0 9 1 Contusion 5 0 0 0 Eczema 0 0 5 0 Enuresis 5 0 0 0 Fall 10 0 0 4 Headache 8 0 0 2 Laryngitis 0 0 5 0 Negativism 5 0 0 0 Status epilepticus 3 0 12 2 Urinary tract infection 5 0 5 0 Viral infection 0 0 5 1 Lennox-Gastaut Syndrome In the placebo-controlled trial of patients with LGS taking concomitant standard of care AEDs (Study 3), 176 patients were treated with FINTEPLA and 87 patients received placebo [see Clinical Studies (14.2) ] . The duration of treatment in this trial was 16 weeks. The mean age was 13.7 years (range 2 to 35 years) and 29% of patients were at least 18 years of age, 45% of patients were female, and 79% were White. All patients were receiving at least one other AED. The rates of discontinuation as a result of any adverse reaction were 6% and 5% for patients treated with FINTEPLA 0.7 mg/kg/day and 0.2 mg/kg/day, respectively, compared to 1% for patients on placebo. The most frequent adverse reactions leading to discontinuation in the patients treated with any dose of FINTEPLA were seizure (2%) and somnolence (2%). The common adverse reactions that occurred in patients treated with FINTEPLA (incidence at least 10% and greater than placebo) were diarrhea; decreased appetite; fatigue; somnolence; vomiting. Table 5 lists the adverse reactions that were reported in 5% or more of patients treated with FINTEPLA and at a rate greater than those on placebo during the titration and maintenance phases of Study 3. Table 5: Adverse Reactions in 5% or More of Patients Treated with FINTEPLA and Greater Than Placebo in the Placebo-Controlled Trial for Lennox Gastaut Syndrome (Study 3) Adverse Reaction FINTEPLA Dose Group Study 3 Placebo Group 0.2 mg/kg/day 0.7mg/kg/day N=89 % N=87 % N=87 % Decreased appetite 20 36 12 Fatigue, malaise, asthenia 14 24 16 Somnolence, sedation, lethargy 12 22 16 Diarrhea 11 13 5 Constipation 6 9 6 Vomiting 14 8 6 Weight decreased 2 8 2 Upper respiratory tract infection 8 7 3 Seizure 9 5 7 Irritability 8 3 6 Echocardiographic Safety Assessments of Valvular Heart Disease and Pulmonary Arterial Hypertension Valvular heart disease and pulmonary arterial hypertension were evaluated in the placebo- controlled and open-label extension studies via echocardiography for up to 3 years in duration for 341 DS patients and 263 LGS patients [see Warnings and Precautions (5.1) ]. Screening for valvular heart disease assessed for mild or greater aortic regurgitation or moderate or greater mitral regurgitation, and assessed for additional characteristics of VHD (e.g., valve thickening or restrictive valve motion). […]
Drug interactions
Dose adjustment is required for patients taking stiripentol plus clobazam. ( 2.2 , 2.3 , 7.1 ) Strong CYP1A2 or CYP2D6 inhibitors: a dose adjustment is recommended ( 2.3 , 7.1 ) Strong CYP1A2, CYP2B6, or CYP3A4 inducers: it is recommended to avoid coadministration with FINTEPLA. If coadministration is necessary, consider a FINTEPLA dosage increase. ( 7.1 )
7.1 Effect of Other Drugs on FINTEPLA Stiripentol Plus Clobazam Coadministration of FINTEPLA with stiripentol plus clobazam, with or without valproate, increases fenfluramine plasma concentrations [see Clinical Pharmacology (12.3) ]. If FINTEPLA is coadministered with stiripentol plus clobazam, the maximum daily dosage of FINTEPLA is 0.2 mg/kg twice daily (maximum daily dosage of 17 mg) [see Dosage and Administration (2.2) ] . Strong CYP1A2, CYP2B6, or CYP3A Inducers Coadministration of FINTEPLA with strong CYP1A2, CYP2B6, or CYP3A inducers will decrease fenfluramine plasma concentrations, which may lower the efficacy of FINTEPLA [see Clinical Pharmacology (12.3) ] . It is recommended to avoid coadministration of strong CYP1A2, CYP2B6 or CYP3A inducers. If coadministration of a strong CYP1A2, CYP2B6, or CYP3A inducer with FINTEPLA is necessary, monitor the patient for reduced efficacy and consider increasing the dosage of FINTEPLA as needed; however, do not exceed the maximum daily dosage of FINTEPLA [see Dosage and Administration (2.2) ]. If a strong CYP1A2, CYP2B6, or CYP3A inducer is discontinued during maintenance treatment with FINTEPLA, consider gradual reduction in the FINTEPLA dosage to the dose administered prior to initiating the inducer [see Warnings and Precautions (5.6) ]. Strong CYP1A2 or CYP2D6 Inhibitors Coadministration of FINTEPLA with strong CYP1A2 or CYP2D6 inhibitors will increase fenfluramine plasma concentrations [see Clinical Pharmacology (12.3) ] . If FINTEPLA is coadministered with strong CYP1A2 or CYP2D6 inhibitors, the maximum daily dosage of FINTEPLA is 20 mg [see Dosage and Administration (2.3) ]. If a strong CYP1A2 or CYP2D6 inhibitor is discontinued during maintenance treatment with FINTEPLA, consider gradual increase in the FINTEPLA dosage to the dose recommended without CYP1A2 or CYP2D6 inhibitors; however, do not exceed the maximum daily dosage of FINTEPLA [see Dosage and Administration (2.2) ]. If FINTEPLA is coadministered with stiripentol and a strong CYP1A2 or CYP2D6 inhibitor, do not exceed the maximum daily dosage of FINTEPLA of 17 mg [see Dosage and Administration (2.3) ].
7.2 Effects of Serotonin Receptor Antagonists Cyproheptadine and potent 5-HT1A, 5-HT1D, 5-HT2A, and 5-HT2C serotonin receptor antagonists may decrease the efficacy of FINTEPLA. If cyproheptadine or potent 5–HT1A, 5–HT1D, 5-HT2A, or 5-HT2C serotonin receptor antagonists are coadministered with FINTEPLA, patients should be monitored appropriately.
7.3 Serotonergic Drugs Concomitant administration of FINTEPLA and drugs (e.g., SSRIs, SNRIs, TCAs, MAO inhibitors, trazodone, etc.), over-the-counter medications (e.g., dextromethorphan), or herbal supplements (e.g., St. John's Wort) that increase serotonin may increase the risk of serotonin syndrome [see Warnings and Precautions (5.7) ]. Concomitant use of FINTEPLA is contraindicated within 14 days of taking MAOIs. Use FINTEPLA with caution in patients taking other medications that increase serotonin.
Pregnancy, breastfeeding, children and older adults
Pregnancy: Based on animal data, may cause fetal harm ( 8.1 )
8.1 Pregnancy Pregnancy Exposure Registry There is a pregnancy exposure registry that monitors pregnancy outcomes in women exposed to antiepileptic drugs (AEDs), such as FINTEPLA, during pregnancy. Encourage women who are taking FINTEPLA during pregnancy to enroll in the North American Antiepileptic Drug (NAAED) Pregnancy Registry by calling the toll-free number 1-888-233-2334 or visiting http://www.aedpregnancyregistry.org. Risk Summary There are no data on FINTEPLA use in pregnant women. Available data from epidemiologic studies with fenfluramine or dexfenfluramine are insufficient to evaluate for a drug-associated risk of major birth defects, miscarriage, or other adverse maternal or fetal outcomes. FINTEPLA can cause decreased appetite and decreased weight [see Warnings and Precautions (5.3) ]; monitor for adequate weight gain during pregnancy. In animal studies, administration of fenfluramine throughout organogenesis (rat and rabbit) or throughout gestation and lactation (rat) resulted in adverse effects on development (fetal malformations, embryofetal and offspring mortality and growth impairment) in the presence of maternal toxicity at clinically relevant maternal plasma levels of fenfluramine and its major active metabolite (see Data ) . All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. 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. Clinical Considerations Disease-associated Maternal and/or Embryofetal Risk Epilepsy, with or without exposure to antiepileptic drugs, has been associated with several adverse outcomes during pregnancy, including preeclampsia, preterm labor, antepartum and postpartum hemorrhage, placental abruption, poor fetal growth, prematurity, fetal death, and maternal mortality. The risk of maternal or fetal injury may be greatest for patients with untreated or poorly controlled convulsive seizures. Women with epilepsy who become pregnant should not abruptly discontinue antiepileptic drugs, including FINTEPLA, due to the risk of status epilepticus or severe seizures, which may be life-threatening [see Warnings and Precautions (5.6) ]. Data Animal Data Oral administration of fenfluramine (0, 4.5, 8.6, or 34.6 mg/kg/day) to pregnant rats during organogenesis resulted in decreased fetal body weights and marked increases in fetal malformations (external, visceral, and skeletal) at the highest dose tested, which was associated with maternal toxicity. At the no-effect dose (8.6 mg/kg/day) for adverse effects on embryofetal development in rats, maternal plasma exposures (AUC) of fenfluramine and norfenfluramine (the major metabolite) were approximately 2 and 5 times, respectively, those in humans at the maximum recommended human dose (MRHD) of 26 mg/day. Oral administration of fenfluramine (0, 4.3, 8.6, 13.0 mg/kg/day) to pregnant rabbits throughout organogenesis resulted in increased embryofetal mortality at all doses and increases in fetal malformations (external and skeletal) at the highest dose tested, which was associated with maternal toxicity. A no-adverse-effect dose for adverse effects on embryofetal development in rabbits was not identified. At the lowest dose tested in rabbits (4.3 mg/kg/day), maternal plasma exposures of fenfluramine and norfenfluramine were lower than those in humans at the MRHD. Oral administration of fenfluramine (0, 4.3, 8.6, or 34.6 mg/kg/day) to female rats throughout gestation and lactation resulted in marked increases in stillborn pups and neonatal offspring deaths at the highest dose tested and delayed growth and reflex development during the pre- weaning period at all doses. Maternal body weight gain was decreased at all doses during pregnancy and at the two highest doses during lactation. A no-effect dose for adverse effects on pre- and postnatal development in rats was not determined. At the lowest dose tested in rats (4.3 mg/kg/day), maternal plasma exposures of fenfluramine and norfenfluramine were approximately 0.5 and 3 times, respectively, those in humans at the MRHD.
8.2 Lactation Risk Summary There are no data on the presence of fenfluramine or its metabolites in human milk, the effects on the breastfed infant, or the effects on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for FINTEPLA and any potential adverse effects on the breastfed infant from FINTEPLA or from the underlying maternal condition.
8.3 Females and Males of Reproductive Potential Infertility In animal studies, oral administration of fenfluramine resulted in adverse reproductive effects in males and females at clinically relevant doses in the presence of parental toxicity [see Nonclinical Toxicology (13.1) ] .
8.4 Pediatric Use The safety and effectiveness of FINTEPLA for the treatment of seizures associated with DS and LGS have been established in patients 2 years of age and older. Use of FINTEPLA for the treatment of seizures associated with DS in patients 2 years of age and older is supported by two randomized, double-blind, placebo-controlled trials in 202 patients 2 to 18 years of age. Use of FINTEPLA for the treatment of seizures associated with LGS is supported by a randomized, double-blind, placebo-controlled study in 263 patients aged 2 to 35 years, including 187 patients less than 18 years [see Boxed Warning , Warnings and Precautions (5) , Adverse Reaction (6.1) , and Clinical Studies (14) ]. FINTEPLA can cause decreases in appetite and weight. The growth of pediatric patients treated with FINTEPLA should be carefully monitored. Safety and effectiveness in patients less than 2 years of age have not been established. Juvenile Animal Data Oral administration of fenfluramine (0, 3.0, 7.8, or 17.3 mg/kg/day) to young rats for 10 weeks starting on postnatal day 7 resulted in reduced body weight and neurobehavioral changes (decreased locomotor activity and learning and memory deficits) at all doses tested. Neurobehavioral effects persisted after dosing was discontinued. Bone size was decreased at the mid and high doses; brain size was decreased at the highest dose. Partial or complete recovery was seen for these endpoints. A no-effect dose for postnatal developmental toxicity was not identified. The lowest dose tested (3.0 mg/kg/day) was associated with plasma fenfluramine exposures (AUC) less than that in humans at the maximum recommended human dose (MRHD) of 26 mg/day and norfenfluramine (metabolite) exposures (AUC) approximately 2 times that in humans at the MRHD.
8.5 Geriatric Use Clinical studies of FINTEPLA for the treatment of DS or LGS did not include patients 65 years of age and over to determine whether they respond differently from younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.
8.6 Renal Impairment In patients with estimated glomerular filtration rate (eGFR) 15 to 29 mL/min/1.73m 2 , do not exceed the maximum daily dosage of FINTEPLA of 20 mg . In patients with eGFR 15 to 29 ml/min/1.73m 2 and concomitant stiripentol use, do not exceed the maximum daily dosage of FINTEPLA of 17 mg [see Dosage and Administration (2.4) and Clinical Pharmacology (12.3) ]. FINTEPLA has not been studied in patients with eGFR < 15 mL/min/1.73m 2 .
8.7 Hepatic Impairment Combined molar exposures of fenfluramine and norfenfluramine were increased in subjects with various degrees of hepatic impairment (Child-Pugh Class A, B, and C), necessitating a dosage adjustment in these patients [see Dosage and Administration (2.5) and Clinical Pharmacology (12.3) ] .
How it works
The precise mechanism by which fenfluramine exerts its therapeutic effects in the treatment of seizures associated with Dravet syndrome and Lennox-Gastaut syndrome is unknown. Fenfluramine and the metabolite, norfenfluramine, exhibit agonist activity at serotonin 5-HT2 receptors. There is an association between serotonergic drugs with 5-HT2B receptor agonist activity, including fenfluramine and norfenfluramine, and valvular heart disease and pulmonary arterial hypertension.
Is there a generic Fenfluramine?
Yes. The FDA has approved generic Fenfluramine from 1 company, and the approval is active.
An FDA approval does not always mean the generic is already in pharmacies: patent disputes and settlements can delay a launch for years. Your pharmacist can tell you whether a generic is actually available and covered by your plan.
Companies with an approved generic
Apotex Inc
Brand-name versions
- Fintepla Ucb Inc, approved 2020
Source: Drugs@FDA (via openFDA), checked October 29, 2026. Marketing status is what companies report to the FDA; whether a pharmacy stocks a product, and what your insurance covers, can differ.
Dosage:
we do not reproduce dosing instructions. The right dose depends on the person and the condition and is set by the prescriber or pharmacist. Dosage section of the full label.
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Source: FDA structured product labeling, retrieved through openFDA. Label text is shown as published by the FDA, without editing; long sections are shortened, marked […]. openFDA data are not validated for clinical use — always check the current label and ask a doctor or pharmacist about your own treatment. Set ID e88f360e-33ad-4cd6-b2de-5ef885857c5d.