Glaser's "Chemistry is in the News"
To Accompany Wade Organic Chemistry 4/e.
Chapter 24. Amino Acids, Peptides, and Proteins.
Throughout time human beings have been seeking to improve themselves, over the passed three decades most people have tried to improve/ change their physical appearance. Undoubtedly the largest concern of most individuals is obesity. In consequence there have been many methods implemented for weight loss, among these chemical, has had a profound affect on the populace.
Invented in France during the 1970's, Fen-phen is a combination of two amphetamines; fenfluramine and phentermine. Use the ChemFinder to see what their structures are. Both drugs work in suppressing the appetite (anorexiants). One, fenfluramine, increases the production of seratonin (a neurotransmitter that lets you know when your full) in the brain while the other, phentermine, boosts the metabolism. Resulting in higher metabolism and a smaller appetite people began to lose weight. After its approval in 1996 for the short term management of obesity, some 6.6 million prescriptions were written for those wanting to drop weight. However, like most chemical substances Fen-phen reacts with the body's chemistry creating some intended effects and some undesired side effects. One report done by the Mayo Clinic disclosed some of these side effects, most importantly valvular heart disease. A rare but serious condition, valvular heart disease was found to have developed in women whom had taken the drug on an average of about 9 months. However, these were the findings of a rather limited research -33 women serviced by the Mayo Clinic as compared to the 6.6 million who received prescriptions, and there was no control group.
Yet, the fact that it is a very rare disease that occurred in 33 women taking Fen-phen, none of whom had a family history for the disease, is quite disconcerting. This did not cause great concern in many of the Fen-phen users, however it did spark an investigation by the FDA resulting in a retraction of the drug in September of 1997.
Pertinent Text References
Chapter 24: Amino Acids, Peptides and Proteins
Question 1: Why is Fen-phen suggested as a short term management for obesity?
Question 2: What effects do fenfluramine and phentermine have on the body's chemistry?
Question 3:Do you think that the FDA was justified in retracting Fen-Phen with the evidence provided from the Mayo Clinic?
Question 4: How does Fen-phen affect the heart's function?
Question 5: Looking at the risks of obesity
and the risks of taking Fen-phen which do you think
poses the most serious health risk ? (For more detail on the affects of
obesity go here.
A. 1: The fenfluramine present in Fen-phen increases the risk of pulmonary hypertension 23 times. Since pulmonary hypertension causes high blood pressure in the arteries, prolonged use of Fen-phen could result in a weakening of the heart valves.
A. 2: Fenfluramine raises the concentration of the neurotransmitter seratonin in the brain causing the stomach to feel satiated. Phentermine boosts the metabolism, yet at the same time it interferes with the pulmonary clearance of seratonin.
A. 3: In the group's opinion the FDA was justified in retracting the drug until further experimentation could be done.
A. 4: High levels of seratonin have been shown to create a white film on the inside of the artery walls while at the same time constricting the blood vessels. This results in having the heart work harder and eventually weakening it, causing a back flow of blood and serious damage to the heart muscle. '