What is Fenfluramine: Uses, Dosage, Side Effects and More

Fenfluramine is a prescription medication primarily used to treat seizures in people with Dravet syndrome, a rare and severe form of epilepsy. This medication works by helping to reduce the frequency and severity of seizures, particularly the difficult-to-control seizures that characterize this condition.

While fenfluramine was once used for weight loss decades ago, today's medical use focuses entirely on seizure management. The medication you might encounter today is specifically formulated and approved for treating epilepsy, not for weight control purposes.

What is Fenfluramine?

Fenfluramine is a serotonin-releasing medication that affects brain chemistry to help control seizures. It belongs to a class of drugs that work by increasing serotonin levels in specific areas of the brain responsible for seizure activity.

The medication comes as an oral solution that you take by mouth. It's specifically designed for people with Dravet syndrome, a genetic form of epilepsy that typically begins in infancy and can be very challenging to treat with other seizure medications.

Your doctor will carefully monitor your response to this medication, as it requires regular check-ups to ensure it's working effectively and safely for your specific situation.

What is Fenfluramine Used For?

Fenfluramine is primarily prescribed to reduce seizure frequency in people with Dravet syndrome. This rare genetic epilepsy condition affects roughly 1 in 15,000 to 20,000 people and often doesn't respond well to standard seizure medications.

The medication specifically helps with the prolonged, severe seizures that characterize Dravet syndrome. These seizures can be particularly dangerous and disruptive to daily life, making effective treatment crucial for both safety and quality of life.

In some cases, doctors might also consider fenfluramine for other rare seizure disorders, but this would be an off-label use requiring careful medical supervision and discussion about potential benefits and risks.

How Does Fenfluramine Work?

Fenfluramine works by increasing serotonin levels in your brain, particularly in areas that control seizure activity. Think of serotonin as a chemical messenger that helps nerve cells communicate more effectively and calmly.

This medication is considered moderately strong in terms of seizure control. It doesn't work the same way as many other seizure medications, which is why it can be helpful when other treatments haven't provided enough seizure control.

The increased serotonin activity helps stabilize the electrical activity in your brain, making seizures less likely to occur. This process takes time to build up in your system, which is why you might not see the full benefits immediately.

How Should I Take Fenfluramine?

Take fenfluramine exactly as your doctor prescribes, usually twice daily with or without food. The medication comes as an oral solution that you measure carefully using the provided measuring device.

You can take this medication with water, milk, or juice if that makes it easier to swallow. There aren't specific food restrictions, but taking it with food might help reduce any stomach upset you might experience.

It's important to take your doses at roughly the same times each day to maintain steady levels in your bloodstream. Set reminders if needed, as consistent timing helps the medication work most effectively.

Your doctor will likely start you on a lower dose and gradually increase it based on how well you respond and any side effects you experience. Never adjust your dose without talking to your healthcare provider first.

How Long Should I Take Fenfluramine For?

Fenfluramine is typically a long-term treatment for managing seizures in Dravet syndrome. Most people need to continue taking it indefinitely to maintain seizure control, as stopping suddenly can lead to increased seizure activity.

Your doctor will regularly evaluate how well the medication is working for you, usually every few months initially, then less frequently once your seizures are well-controlled. These check-ups help determine if fenfluramine continues to be the right choice for your situation.

If you and your doctor decide to stop fenfluramine, this process requires careful planning and gradual dose reduction. Stopping seizure medications suddenly can be dangerous and may trigger more frequent or severe seizures.

What Are the Side Effects of Fenfluramine?

Like all medications, fenfluramine can cause side effects, though many people tolerate it well. The most common side effects are generally mild and often improve as your body adjusts to the medication.

Here are the side effects you're most likely to experience, keeping in mind that many people have few or no bothersome effects:

• Decreased appetite and weight loss
• Fatigue or feeling more tired than usual
• Drowsiness or sleepiness
• Diarrhea or loose stools
• Constipation
• Fever
• Upper respiratory tract infections

These common side effects often become less noticeable after a few weeks as your body adapts to the medication. However, let your doctor know if they persist or become bothersome.

Some less common but more serious side effects require immediate medical attention. While these are rare, it's important to be aware of them:

• Heart valve problems or heart murmurs
• Pulmonary hypertension (high blood pressure in the lungs)
• Significant mood changes or depression
• Severe allergic reactions
• Glaucoma or increased eye pressure

Your doctor will monitor you carefully for these more serious effects through regular check-ups and may order periodic heart tests to ensure the medication remains safe for you.

Who Should Not Take Fenfluramine?

Fenfluramine isn't suitable for everyone, and your doctor will carefully review your medical history before prescribing it. Certain health conditions make this medication potentially unsafe or less effective.

You should not take fenfluramine if you have any of these conditions, as they could increase your risk of serious complications:

• Heart valve disease or heart murmurs
• Pulmonary hypertension
• Severe liver or kidney disease
• Glaucoma or increased eye pressure
• Known allergy to fenfluramine or similar medications

Additionally, tell your doctor about all other medications you're taking, as fenfluramine can interact with certain drugs, particularly other serotonin-affecting medications and some antidepressants.

Pregnancy and breastfeeding require special consideration. While seizure control during pregnancy is important, your doctor will need to weigh the benefits against potential risks to your baby.

Fenfluramine Brand Names

Fenfluramine is available under the brand name Fintepla in the United States. This is the specific formulation approved by the FDA for treating seizures associated with Dravet syndrome.

The brand name Fintepla helps distinguish this modern seizure medication from older fenfluramine formulations that were once used for weight loss but are no longer available. Always use the specific brand and formulation your doctor prescribes.

Generic versions of fenfluramine for seizure treatment are not yet widely available, so most prescriptions will be filled with the brand name Fintepla.

Fenfluramine Alternatives

Several other medications can help manage seizures in Dravet syndrome, though the best choice depends on your individual response and medical history. Your doctor might consider these alternatives if fenfluramine isn't suitable or effective for you.

Common alternatives include stiripentol, clobazam, valproic acid, and topiramate. Each works differently in the brain and may be more or less effective depending on your specific seizure pattern and other health factors.

Cannabis-based medications like cannabidiol (CBD) are also approved for Dravet syndrome and might be considered as alternatives or additions to fenfluramine, depending on your situation.

Never switch medications without working closely with your doctor, as seizure medications require careful transitioning to avoid breakthrough seizures or withdrawal effects.

Is Fenfluramine Better Than Other Seizure Medications?

Fenfluramine offers unique benefits for people with Dravet syndrome, particularly because it works through a different mechanism than many other seizure medications. This different approach can be especially helpful when other treatments haven't provided adequate seizure control.

Clinical studies show that fenfluramine can significantly reduce seizure frequency in many people with Dravet syndrome, often providing better control than some traditional seizure medications alone. However, "better" depends on your individual response and tolerance.

The advantage of fenfluramine is that it can be used alongside other seizure medications, potentially providing additional seizure control without necessarily replacing treatments that are partially helpful.

Your doctor will consider your seizure history, other medical conditions, and how well you've responded to previous treatments when determining if fenfluramine is the right choice for your specific situation.