From the Micromedex database:
FENFLURAMINE (fen-FLUR-a-meen):
Used for short periods of time as part of a diet plan to help you lose weight.
BRAND NAME(S): Pondimin®
WHEN YOU SHOULD NOT USE THIS MEDICINE:
You should not use this medicine if you have had an allergic reaction to fenfluramine or related medicines such as amphetamines, asthma medicine (metaproterenol, terbutaline, or isoproterenol), or certain cold and allergy medicine (decongestants such as ephedrine, pseudoephedrine, or phenylpropanolamine).
You should not use this medicine if you have problems with drug or alcohol abuse, heart disease, or glaucoma. You should not use fenfluramine if you have taken a type of medicine called a MAO inhibitor (such as Nardil®, Marplan®, or Parnate®) within the past 14 days. These 2 medicines taken together or within 14 days of each other can cause dangerously high blood pressure.
DRUGS AND FOODS TO AVOID:
Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.
Avoid drinking alcohol while taking this medicine.
Make sure your doctor knows if you are also taking blood pressure medicine, medicine to treat depression, or any medicine that may make you sleepy, such as sleeping pills, tranquilizers, some cold or allergy medicines, or strong pain killers.
WARNINGS:
Check with your doctor before taking this medicine if you have high blood pressure or have had problems with depression.
A rare side effect caused by fenfluramine is called pulmonary hypertension, or high blood pressure in the lungs. Most people will not have this problem, but if you start to have trouble breathing or easily become short of breath, have chest pain, or swelling in your feet or lower legs call your doctor right away. This is a very serious problem.
Fenfluramine can be habit-forming. You may have withdrawal symptoms such as a depressed mood, tiredness, or anxiety after you stop taking the medicine.
If you have taken this medicine for a long time, do not suddenly stop taking it. Talk to your doctor first. You may need to take smaller and smaller doses before you completely stop taking the medicine.
If the medicine does not seem to work as well after a few weeks, talk to your doctor. You should not use more of it than your doctor prescribed.
This medicine may make you dizzy or sleepy Be careful if you are driving a car or using machinery.
Talk with your doctor before taking this medicine if you are pregnant or breastfeeding.
Tell your doctor or dentist that you are taking fenfluramine before having any kind of surgery.
This medicine works best if you follow a low-calorie diet and excercise regularly.
SIDE EFFECTS
Call your doctor right away if you have any of these side effects:
Trouble breathing or feeling short of breath
Fast or irregular heartbeat
Chest pain
Severe headache
Blurred vision, confusion, or hallucinations
If you have problems with these less serious side effects, talk with your doctor.
Nausea, diarrhea
Drowsiness
Dry mouth
That said...
Anything that has the potential to affect the motor complex and/or reasoning centers of the brain is a potential contraindication for diving with it (as noted above in bold in relation to operating machinery). Most medical authorities will agree that talking this over with your prescribing physician is the best course. Also, the potential for dyspnea is something to consider when diving with this medication.
Are there any other thoughts?
