Fenfluramine is used to help control seizures in people with Dravet syndrome.
Fenfluramine may cause heart valve problems (valvular heart disease) and high blood pressure in the lungs (pulmonary arterial hypertension). Medical tests (such as echocardiograms) must be done before, during, and after treatment with this medication. Tell your doctor right away if you have symptoms of these serious side effects, including: shortness of breath, chest pain, fast/irregular heartbeat, lightheadedness, fainting, swelling ankles/feet.
For patients to receive this medication, all doctors, pharmacists, and patients must agree to, understand, and carefully follow the requirements of the Fintepla REMS Program. These requirements apply in the United States. If you live in Canada or any other country, consult your doctor and pharmacist for your country's regulations.
Read the Medication Guide and, if available, the Instructions for Use provided by your pharmacist before you start using fenfluramine and each time you get a refill. If you have any questions, ask your doctor or pharmacist.
Take this medication by mouth with or without food as directed by your doctor, usually twice daily. Carefully measure the dose using the provided measuring device. Do not use a household spoon because you may not get the correct dose.
The dosage is based on your medical condition, weight, response to treatment, and other medications you may be taking. Be sure to tell your doctor and pharmacist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).
To reduce your risk of side effects, your doctor may direct you to start this medication at a low dose and gradually increase your dose. Follow your doctor's instructions carefully. Take this medication regularly to get the most benefit from it. To help you remember, take it at the same times each day.
Do not stop taking this medication without consulting your doctor. Some conditions may become worse when this drug is suddenly stopped. Your dose may need to be gradually decreased.
Tell your doctor if your condition does not get better or if it gets worse.
See also Warning section.
Decreased appetite, weight loss, drowsiness, tiredness, diarrhea, constipation, drooling, or shaking (tremor) may occur. If any of these effects last or get worse, tell your doctor promptly.
Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
This medication may raise your blood pressure. Check your blood pressure regularly and tell your doctor if the results are high.
Tell your doctor right away if you have any serious side effects, including: eye pain/swelling/redness, vision changes (such as seeing rainbows around lights at night, blurred vision).
A small number of people who take anticonvulsants for any condition (such as seizure, bipolar disorder, pain) may experience depression, suicidal thoughts/attempts, or other mental/mood problems. Tell your doctor right away if you or your family/caregiver notice any unusual/sudden changes in your mood, thoughts, or behavior such as signs of depression, suicidal thoughts/attempts, thoughts about harming yourself.
This medication may increase serotonin and rarely cause a very serious condition called serotonin syndrome/toxicity. The risk increases if you are also taking other drugs that increase serotonin, so tell your doctor or pharmacist of all the drugs you take (see Drug Interactions section). Get medical help right away if you develop some of the following symptoms: fast heartbeat, hallucinations, loss of coordination, severe dizziness, severe nausea/vomiting/diarrhea, twitching muscles, unexplained fever, unusual agitation/restlessness.
A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US -
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
Before taking fenfluramine, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: heart problems (such as valvular heart disease), lung disease (such as pulmonary arterial hypertension), weight loss, high blood pressure, mental/mood disorders (such as depression, thoughts of suicide, psychosis), glaucoma, kidney disease, liver disease, personal or family history of a substance use disorder (such as overuse of or addiction to drugs/alcohol).
This drug may make you drowsy. Alcohol or marijuana (cannabis) can make you more drowsy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Avoid alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).
Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).
Children may be more sensitive to the side effects of this drug, especially decreased appetite and weight loss. Monitor weight closely in children who are taking this drug.
During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.
It is unknown if this drug passes into breast milk. Consult your doctor before breast-feeding.
Consult your pharmacist or physician.
Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.
Taking MAO inhibitors with this medication may cause a serious (possibly fatal) drug interaction. Avoid taking MAO inhibitors (isocarboxazid, linezolid, metaxalone, methylene blue, moclobemide, phenelzine, procarbazine, rasagiline, safinamide, selegiline, tranylcypromine) during treatment with this medication. Most MAO inhibitors should also not be taken for two weeks before and after treatment with this medication. Ask your doctor when to start or stop taking this medication.
The risk of serotonin syndrome/toxicity increases if you are also taking other drugs that increase serotonin. Examples include street drugs such as MDMA/"ecstasy," St. John's wort, certain antidepressants (including SSRIs such as fluoxetine/paroxetine, SNRIs such as duloxetine/venlafaxine), among others. The risk of serotonin syndrome/toxicity may be more likely when you start or increase the dose of these drugs.
Tell your doctor or pharmacist if you are using other products that cause drowsiness such as opioid pain or cough relievers (such as codeine, hydrocodone), alcohol, marijuana (cannabis), drugs for sleep or anxiety (such as alprazolam, lorazepam, zolpidem), muscle relaxants (such as carisoprodol, cyclobenzaprine), or antihistamines (such as cetirizine, diphenhydramine).
Check the labels on all your medicines (such as allergy or cough-and-cold products) because they may contain ingredients that cause drowsiness. Ask your pharmacist about using those products safely.
If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: fast heartbeat, widened pupils, muscle spasms, trouble breathing.
Do not share this medication with others. Sharing it is against the law.
Lab and/or medical tests (such as weight, blood pressure, heart function) must be done before you start taking this medication and while you are taking it. Keep all medical and lab appointments. Consult your doctor for more details.
If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.
Store at room temperature away from light and moisture. Do not refrigerate or freeze. Do not store in the bathroom. Discard any unused medication 3 months after first opening the bottle. Keep all medications away from children and pets.
Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.