More <

Fenfluramine (By mouth)

Fenfluramine Hydrochloride (fen-FLUR-a-meen hye-droe-KLOR-ide)

There may be other brand names for this medicine.

This medicine is not right for everyone. Do not use it if you had an allergic reaction to fenfluramine.

Take your medicine as directed. Your dose may need to be changed several times to find what works best for you.
Measure the oral liquid medicine with the marked oral syringe. Do not use a teaspoon or tablespoon to take a dose.
This medicine should come with a Medication Guide. Ask your pharmacist for a copy if you do not have one.
Missed dose: Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose.
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Throw away any unused medicine 3 months after first opening the bottle.

Do not use this medicine if you have used an MAO inhibitor within the past 14 days.
Some medicines can affect how fenfluramine works. Tell your doctor if you are using any of the following:
- Clobazam, cyproheptadine, dextromethorphan, lithium, rifampin, stiripentol, St John's wort, tramadol, tryptophan, valproate
- Medicine to treat depression and other mental problems (including bupropion, fluvoxamine, paroxetine, trazodone, SSRIs, SNRIs, TCAs)
Do not drink alcohol while you are using this medicine.
Tell your doctor if you use anything else that makes you sleepy. Some examples are allergy medicine, narcotic pain medicine, and alcohol.

Tell your doctor if you are pregnant or breastfeeding, or if you have kidney disease, liver disease, heart disease, lung or breathing problems, depression, high blood pressure, or eye or vision problems.
This medicine may cause the following problems:
- Heart problems (including valvular heart disease)
- Pulmonary arterial hypertension (high blood pressure in the lungs)
- Loss of appetite and weight
- Changes in mood or behavior, including thoughts of suicide
- Serotonin syndrome (when used with certain other medicines)
- High blood pressure
- Eye or vision problems (including glaucoma)
This medicine may make you dizzy or drowsy. Do not drive or do anything else that could be dangerous until you know how this medicine affects you.
This medicine can be habit-forming. Do not use more than your prescribed dose. Call your doctor if you think your medicine is not working.
Do not stop using this medicine suddenly. Your doctor will need to slowly decrease your dose before you stop it completely.
Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.
Keep all medicine out of the reach of children. Never share your medicine with anyone.

Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
Anxiety, restlessness, fast heartbeat, fever, sweating, muscle spasms, nausea, vomiting, diarrhea, seeing or hearing things that are not there
Changes in vision, eye pain, seeing halos around lights
Decreased appetite, weight loss
Dizziness, headache, slow, fast or uneven heartbeat
Fever, chills, cough, stuffy or runny nose, sore throat, body aches
Thoughts of hurting yourself or others, worsening depression, unusual behavior
Trouble breathing, chest pain or tightness, swelling of the feet or lower legs
Twitching or muscle movements you cannot control, problems with balance or walking
Unusual tiredness or weakness

Last Updated: 4/23/2024