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Dexfenfluramine HCl oral

Important Note

The following information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist or other healthcare professional. It should not be construed to indicate that use of the drug is safe, appropriate, or effective for you. Consult your healthcare professional before using this drug.





This medication is used in the treatment of obesity. It helps promote and manage weight loss in persons on a reduced calorie diet. This drug has been withdrawn from the U.S. market due to safety or effectiveness problems.

How To Use

Take this by mouth as directed usually twice a day with meals. Do not increase your dose or take this more often than directed since the risk of side effects will be increased.

Side Effects

Drowsiness, diarrhea, gas, nausea, headache, dry mouth, runny nose, sweating, altered sense of taste, constipation, heartburn, anxiety, insomnia or depression may occur. If these effects continue or become severe, inform your doctor. Notify your doctor if you experience: breathing trouble, chest pain, dizziness, fainting, vision changes, stomach pain, swelling of the feet or ankles, rapid pulse, unusual weakness, muscle aches skin rash. To relieve dry mouth, suck on (sugarless) hard candy or ice chips, chew (sugarless) gum, drink water or use saliva substitute. In the unlikely event you have an allergic reaction to this drug, seek immediate medical attention. Symptoms of an allergic reaction include: rash, itching, swelling, dizziness, breathing trouble. If you notice other effects not listed above, contact your doctor or pharmacist.


Before taking this drug, tell your doctor if you have: heart disease, high blood pressure, lung disease (pulmonary hypertension), breathing problems, thyroid problems, glaucoma, liver disease, any allergies. Limit intake of alcoholic beverages. Use caution while driving or performing tasks requiring alertness as this drug may cause drowsiness. This medication should not be used during pregnancy or while breast-feeding. If you become pregnant or think you may be pregnant, inform your doctor immediately. This drug should be used with caution in the elderly.

Drug Interactions

Tell your doctor of all prescription and non- prescription medication you may take, especially: MAO inhibitors (e.g., furazolidone, linezolid, phenelzine, selegiline, tranylcypromine), SSRI antidepressants (e.g., fluoxetine), migraine headache drugs (e.g., ergot drugs, sumatriptan). Do not start or stop any medicine without doctor or pharmacist approval.


If overdose is suspected, contact your local poison control center or emergency room immediately. Symptoms of overdose may include agitation, drowsiness, nausea, vomiting, tremor, shivering, fever, sweating, stomach pain, dilated pupils, fast heartbeat, and seizures.


For best results, this is used along with any dietary guidelines or other weight loss programs recommended by your doctor. The most noticeable results are seen in the first 4 to 6 weeks. If you are scheduled for a urine drug screen, be aware that this medication can cause false-positive results for amphetamines.

Missed Dose

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 and resume your usual dosing schedule. Do not "double-up" the dose to catch up.


Store at room temperature between 59 and 86 degrees F (15 to 30 degrees C) away from moisture and light as directed. Do not store in the bathroom. Keep out of the reach of children.

Medical Alert

Your condition can cause complications in a medical emergency. For enrollment information call MedicAlert at 1-800-854-1166 (USA), or 1-800-668-1507 (Canada).