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Generic Name: Phentermine
Brand Name(s):
Information updated: April 1, 2000
Overview
Phentermine is a fairly old prescription diet drug that has made a recent
comeback.
Although not an amphetamine, it is similar in many respects
and is classified as a controlled substance.
Phentermine is approved for
relatively short-term use as an appetite suppressant in a calorie-restricted
weight loss program.
Phentermine became immensely popular as part of the
combination fen-phen. Bur reports of heart valve problems and primary pulmonary
hypertension led to the withdrawal of fenfluramine, the other part of that
combination.
Side Effects and Interactions
Phentermine can cause reactions such as
palpitations, rapid heart beat, higher blood pressure, overstimulation,
insomnia, restlessness, dizziness, dry mouth, or diarrhea.
Other
reactions that have been reported include headache, tremor, constipation,
digestive disturbances, metallic taste, hives, impotence, and alteration in sex
drive.
A few people on phentermine have suffered strokes. Report any
symptoms or suspected side effects to the physician promptly.
Phentermine
should not be taken with an MAO inhibitor such as Nardil or Parnate.
Phentermine may also interact with insulin, many diabetes pills, and the
blood pressure pill guanethidine.
Phentermine may react with beta
blockers such as propranolol.
Some sources advise against alcohol
consumption for people on phentermine. Check with your doctor and pharmacist
before taking any other medicine while taking phentermine.
Special Precautions
Phentermine is inappropriate for people with glaucoma, serious high blood pressure, symptomatic heart disease, or hyperthyroidism.
Phentermine must not be combined with MAO inhibitor drugs (Eldepryl, Nardil, Parnate) and a person should wait at least 14 days after stopping any of these before starting to take phentermine.
Phentermine is not recommended for people in agitated states of mind or who have problems with drug abuse or alcoholism.
The effectiveness of this drug against the sensation of hunger may wear off after a few weeks.
The dose should not be raised in an attempt to maintain the effect; abuse of the drug can result in skin problems, insomnia, irritability, hyperactivity, and personality changes or even psychosis.
Sudden withdrawal may result in depression and extreme fatigue.
Taking the Medicine
Phentermine is taken once a day, usually two hours after breakfast.
Ionamin (phentermine
resin, which is absorbed more slowly) is to be taken before breakfast, or 14 hours before bedtime.
The capsules are to be swallowed whole.
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Joe Graedon is a pharmacologist. Teresa Graedon holds a doctorate in medical anthropology and is a nutrition expert. Their syndicated radio show can be heard on public radio.
© 2000