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A Closer look at The Use of Appetite Suppressants
 Elizabeth Kilburn Deuchler


In the past two decades, Americans and most of the Western world have become obsessed with losing weight. Countless diets, weight loss strategies and gimmicks have been and remain on the market and cost Americans billions of dollars every year. The media perpetuates this ideal of thinness and so people continue in desperate attempts to shrink their bodies. People have gone to extreme measures such as stomach stapling, liposuction and starvation diets to try and take off excess weight. Many Americans are willing to do whatever is necessary to look a certain way, no matter what the cost. Sometimes these costs outweigh the benefits of losing weight. Oftentimes, when people diet and lose weight, they end up going off the diet and gaining the weight back. This leads to a perpetual cycle of yo -yo dieting. Nevertheless, the quest for losing weight remains a priority in many people’s lives.

One of the options that many people have taken in attempt to lose weight is the ingestion of various appetite suppressants. The logic behind this is that if one takes an appetite suppressant, they wont feel hungry. Without hunger, the person will ingest less food and by ingesting less food, the person will lose weight. The concept is actually quite simple and has been around for many years. Hunger is “the physiological need of an animal for food (Lasagna, p.132).” Appetite, on the other hand, is “the psychological motivation for food intake- which is independent of the individual’s nutritional state (Lasagna, p.132).” An appetite suppressant attempts to lessen a person’s psychological motivation for food, even though there might be a need for food intake for nutritional reasons.  Phenylpropanolamine, one of the most prevalent appetite suppressants on the market today, limits the appetite because of its effect on the hypothalamus, which is a control center in the brain. The hypothalamus helps to tell the body when to give off hunger signals. PPA interrupts this system and thus, the individual’s appetite is somewhat curbed. Because the appetite is curbed, the individual desires less food and ultimately loses weight. Appetite Suppressants have been around for a number of years. Some people have actually taken them for years and years in attempt to curb their appetite. One main appetite suppressant that has been around since the early 1900’s is Phenylpropanolamine. Phenylpropanolamine, also known as PPA is the main ingredient in common appetite suppressants like Dexatrim, Vitaslim, Hungrex and Acutrim. PPA is a “non-methylated form of Ephidrine (Morgan, p.3).” PPA first became known as a nasal decongestant and is still used in these over the counter drugs today. Although PPA is the substance found in a number of cough/cold remedies, it is also the active ingredient in most appetite suppressants.

Numerous studies have been done surrounding the effects of PPA on weight loss. Most studies show that using the appetite suppressant, PPA along with diet and exercise will promote weight loss. PPA has been shown to be extremely effective in helping people eat less and achieve the ultimate goal of losing weight. In 1975, a study with 70 volunteers concluded “the subjects lost three times as much weight while taking PPA than while taking the placebo (Lasagna, p.393).” Another study in 1986 was performed on 106 overweight women and it was concluded that the “women who took Acutrim lost significantly more weight than those who took placebo (Lasagna, p.369).” Countless other studies show the same results. However, many of these studies are seriously flawed. Some of these studies restrict caloric intake for their participants, while others increased activity level. Also, many of these studies only included a specific type of individual. For example, in the 1975 study, only middle -aged women were studied. Can we assume these studies are valid? Nevertheless, assuming that they are valid and that PPA really does aid in losing weight, we must also look at the negative effects of the drug. 

There have been hundreds of clinical and non-clinical studies surrounding PPA; it’s effectiveness on weight loss and possible side effects. “In several cases, ingestion of a Phenylpropanolamine-containing product was temporarily associated with cerebrovascular hemorrhage, although a temporal correlation does not necessarily indicate a causal relationship (Elliot & White, 1981; Fallis & Fisher, 1985; Kitka et al. 1985; McDowell & LeBlanc, 1985; Stoessl et al., 1985).” Also, “several cases suggest that individuals with a history of psychiatric disturbances may be at risk for adverse drug reactions to phenylpropanolamine (Anchor and Extein, 1981; Crigg & Goyer, 1986; Cane & Green, 1966).” So as you can see, appetite suppressants containing PPA are somewhat controversial. “At least 4 placebo controlled clinical trials some of which used PPA and caffeine with over 1200 subjects shows that this drug does induce weight loss among its minor side effects are thirst, irritability, palpitation, tiredness and “jitteriness”… this medicine, however, has been shown in hundreds of reports in Medical literature to have very serious side effects such as cardiac arrhythmias, intracerebral hemorrhage, acute dystonia, myocardial injury, psychosis, cerebral arteritis and hypersensitive crisis (PMR, p.681).” However, the Food and Drug administration still allows PPA to remain on the market. Are these potential risks worth losing extra weight?   

In 1983, staff members wrote a book from Ralph Nader’s Health Research Group entitled Over the Counter Pills that don’t work. They write “Despite the FDA panel’s decision, it is our opinion that PPA poses a substantial hazard for its users.” There have been many incidents of adverse reactions to PPA. It should also be noted “It is unlikely that weight loss induced by short term PPA use will have the positive impact on cardiovascular health, osteoarthritis, choleithiasus, adult onset diabetes mellitus or hypertension (Morgan, Kagan p.76).” In other words, because people are likely to lose weight while taking PPA but the weight loss is not so significant as to reduce one’s health risks of being overweight. Studies show that PPA is very helpful in shedding excess pounds, but what happens after the individual stops taking the drug? We can only assume that the weight comes right back on. For example, let’s assume that an individual decides that they want to lose ten pounds. They decide to take dexatrim every day and their hunger diminishes. The individual loses the ten pounds and stops taking dexatrim. Eventually, that person’s hunger returns to normal and the weight is regained. Unless this individual is willing to take the appetite suppressant for the rest of their life, it seems pointless to take them because as soon as they stop taking the PPA, the hunger will return and they will regain the weight that they originally lost. Even if a person decides to take the drug for an extended period of time, there have not been any studies on the prolonged usage of PPA. We do not know if the drug continues to curb appetite even after years or what the potential side effects may be if the individual takes PPA on a daily basis for years. We must also look at the logic behind dieting. Oftentimes, people desperately want to lose weight but cannot because they consume an excess amount of calories than their bodies need. A lot of times, this is caused by emotional eating or overeating. If we as human beings ate only when we were hungry and stopped when we were full, the diet industry would not nearly be as huge as it is today. But, it is not that simple. People eat when they are tired, lonely, and sad or feeling isolated. Sometimes people eat when they are joyous or really happy. In either case, appetite suppressants would not be helpful since people are not eating to satisfy hunger. 

Human beings are the only species in the universe that have such a problem with obesity. This is probably due to our over abundance of food sources and our tendency to link other emotions with feelings of hunger and food. Every other species of animal eats for survival and no other reason. When a cheetah feels hungry, she hunts for food until she finds it and then eats to fullness. But, people are different and this is why appetite suppressants might not work for some individuals because they are not eating to satisfy their appetites, but eating for other reasons. For example, people eat popcorn at the movie theater out of habit, not because they are internally hungry. Hunger and our desire to satisfy it are so natural. With appetite suppressants such as PPA, we are interrupting a very natural occurrence. Nevertheless, people still take appetite suppressants such as PPA in attempt to lose weight and our society actually promotes these appetite suppressants as a safe means of losing weight.

Even though there have been countless adverse reactions to PPA, the FDA still allows it to be sold on the market. Without doing research themselves, people in the United States assume that these appetite suppressants are safe because the FDA has approved them. Little do these people know that these drugs have been known to cause some serious harmful reactions in many people. Various companies sell Phenylpropanolamine in drug stores across the country. Any individual can go into any one of these stores and purchase these drugs without a prescription. Nowadays with the internet and World Wide Web access, people have a new outlet to attain these drugs. Companies can advertise their drugs over the internet and virtually say whatever they please about PPA and it’s effectiveness. The internet is a non-monitored media source. Some people believe everything they read on the internet when, in actuality many of these statements could be false. One website claims, “Each year millions try to lose weight; some will succeed on pure willpower but many will fail because of uncontrollable appetites. Now dieters have a medication capable of controlling hunger safely and effectively. Tested over and over, WEIGHT AWAY is so safe, no prescription is warranted (” Nowhere on this website does it say that PPA might cause harmful side effects. However, it falsely claims that PPA is “so safe.” Although no prescription is necessary to purchase it and the FDA allows it on the market, various studies have shown that PPA does cause harmful side effects.

Some websites provide more accurate information for the general public to access in their search for weight loss through appetite suppressants. One helpful website states that “when used as directed in a comprehensive weight loss program that includes a low fat diet and regular exercise, Acutrim and Dexatrim can increase weight loss by about an additional 5%. However, weight loss may not be permanent, especially after these drugs are discontinued (” This statement can be backed up by scientific research and the website does not neglect to tell the consumer about the potential side effects. On this website, they actually include a listing of the possible side effects including “nervousness, irritability, headache, sweating, dry mouth, nausea and constipation.” One website actually has a link to a section entitled “Common questions about appetite suppressants” Five questions are raised that directly relate to the effectiveness and safety of these sort f drugs. This website is a reprinted version from Prescription Medications for the Treatment of Obesity, a highly respected journal in the medical world. Therefore, one can rely on their advice for reliable and valid information.
Another website claims to have “The dirt on Diet Pills” ( but this website claims that “the worst you can expect {is} dry mouth and eyes, nausea, nervousness, racing heart and increasing blood pressure.” However, they fail to tell the reader about various other possible side effects. One cannot neglect to state that there have been numerous studies showing that PPA has had minimal side effects. We must also take into account the fact that “many of the symptoms attributed to PPA may truly be related to feelings or symptoms caused by fasting or stringent dieting (Morgan, Kagan, p.405).” In other words, the same side effects associated with PPA are also associated with people on a strict diet. Therefore, we cannot assume that the PPA is the direct cause of these side effects. Also, it is important to note “most of the clinical trials, particularly the recent ones and the bioavailability studies were funded by the pharmaceutical industry (Morgan, p.69).” So it is safe to assume that these companies selling these drugs are not going to print literature on trials that they fund that poses their product as a risk to the consumer. Therefore, it is quite likely that these studies might be skewed or biased.          What can we conclude from this information? Basically, PPA is an extremely controversial drug. Countless studies have been done on its effectiveness and safety. Many studies claim that the drug is safe; while others claim that it can cause serious complications through side effects. Some studies claim that the drug works well to lose an initial amount of weight. But after discontinued use, the weight is likely to come right back on. Some studies claim that an initial amount of weight is lost and then PPA has no effect on additional weight loss. Almost every single study is somewhat biased. Many use a specific type of subject and not a randomized group of people. Also, in almost all studies, the individuals are overweight and want to lose weight. What if someone takes PPA who is of normal weight, will they lose weight? What if the subject’s had no desire to lose weight? What if the subjects are not dieting or exercising while taking the drugs? Will they still lose weight? It is important for us to think about the efficacy of these trials before buying into their conclusions. It is very difficult to make any clear statements about PPA since the various studies contradict each other.  
Works Cited
Lasagna, L. (1988). Phenylpropanolamine- A Review.   A Wiley Interscience Publication. Boston, MA.
Morgan, J.P. , Kagan, D.V. (1985). Phenylpropanolamine: Risks, Benefits and Contraversies. Clinical Pharmacology and Therapeutic Services, Volume 5. Preager Publishers. New York, N.Y.
Morgan, J.P. (1986). Phenylpropanolamine: A critical Analysis of Reported Adverse Reactions and Overdosage. Jack. K. Burgess, Inc. Fort Lee, N.J.
Fillmore, C. M. et al. (1999). Nutrition and Dietary Supplements, Phys Med Rehabil Clin N Am, 10, (3), 673-703.
Silverstone, T. (1986). Clinical Use of Appetite Suppressants, Drug and Alcohol Dependence, 17, (2-3), 151-167.
Wellman, P.J. (1990). A Review of the physiological bases of the anorexic action of phenylpropanolamine, Neuroscience and Biobehavioral Reviews, 14 (3), 339-355.
Greenway, F.L. (1992). Clinical Studies with phenylpropanolamine: a metaanalysis, American Journal of Clinical Nutrition, 55, 203-205.
Alger, S. et al. (1993). Effect of Phenylpropanolamine on energy expenditure and weight loss in overweight women,  American Journal of Clinical Nutrition, 57, 120-126.


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