Diet Pills - Effects on the Body
Effects on the Body
The diet pills developed to replace amphetamines became known as anorectics or appetite suppressants. Anorectics are sometimes referred to as sympathomimetic drugs. They are stimulants that "mimic" the body's natural energy-releasing mechanisms. The FDA has approved a variety of anorectics over the years for the shortterm treatment of obesity. Phentermine was approved in 1959, fenfluramine (FENN-FLOOR-uh-meen) in 1973, and dexfenfluramine (deks-FENN-FLOOR-uh-meen) in 1996. Other anorectic diet pills include benzphetamine, diethylpropion, and phendimetrazine.
A different type of prescription diet pill received FDA approval in 1999. The lipase inhibitor orlistat (Xenical) is said to block about 30 percent of the fat absorbed by the body.
The Fen-Phen Craze
In the 1990s, doctors in the United States and other countries began prescribing low doses of fenfluramine (Pondimin) or dexfenfluramine (Redux) along with low doses of phentermine. The combination, known informally as "Fen-Phen," was never approved
by the FDA. Seven million prescriptions for Fen-Phen were written in 1996. "The rationale for using the two drugs," according to a Seattle Times contributor, "was that they might work more effectively together with fewer side effects."
Soon, however, the safety of Fen-Phen was called into question. The appetite-suppressant mixture was thought to be the cause of some severe health problems, including serious heart valve malfunctions. As a result, both fenfluramine and dexfenfluramine were withdrawn from the market in September of 1997. Phentermine is still sold because no cases of heart valve disease have been reported when that drug is taken alone, according to an FDA report.
There Are No Magic Cures
Prescription diet pills help with weight reduction by suppressing the user's appetite and increasing the feeling of fullness in the stomach. But diet pills alone will not make excess weight disappear. According to Patricia Dwyer Schull in the Nursing Spectrum Drug Handbook, prescription drugs for "obesity management" must be "used in conjunction with [a] reduced-calorie diet" in order to be effective.
Diet pills can produce symptoms that range from dizziness to an increased number of bowel movements. Possible side effects include light-headedness, dry mouth, a false feeling of well-being, nausea, irritability, insomniaDifficulty falling asleep or an inability to sleep., trembling, blurred vision, nervousness, increased sweating and urination, and problems with the blood vessels in the lungs.
Sibutramine (Meridia), a prescription diet pill approved by the FDA in 1997, may cause an increase in heart rate and blood pressure. Long-term use of any prescription appetite suppressant can lead to addiction. Taking anorectics can impair a person's ability to drive, operate heavy equipment, or perform other potentially hazardous activities. Sympathomimetics or anorectics should not be prescribed to people with a history of drug abuse.
Taking orlistat, the lipase-inhibiting-type diet pill, can bring on an increased number of bowel movements, gas with discharge, oily or fatty stools, and the inability to control a bowel movement. Because orlistat blocks the absorption of fat in the intestines, the fat is eliminated from the body as part of a bowel movement. Orlistat users may sometimes feel an urgent need to go to the bathroom. These symptoms are often aggravated if the user eats too many high-fat foods.
Women who are pregnant or nursing their babies should consult with their physician about any diet pill use. Most prescription diet pills are not recommended for use by pregnant or nursing women. Diet pills can also affect bone development in children and young adults.
When patients stop taking anorectics, their bodies need to adapt to the lack of drugs in their systems. The amount of withdrawalThe process of gradually cutting back on the amount of a drug being taken until it is discontinued entirely; also the accompanying physiological effects of terminating use of an addictive drug. time will vary, depending on the strength of the dosage taken and the length of time it was used. Withdrawal symptoms may include insomnia, nightmares, nausea, vomiting, and stomach cramps. The user typically experiences strong hunger pangs as well.
Possible Dopamine Connection
A study conducted by the National Institute on Drug Abuse (NIDA) suggests that the same factors that control excessive behaviors such as drug abuse and gambling may be associated with overeating. The main factor may be an abnormality in the brain involving chemical messengers called neurotransmittersA substance that helps spread nerve impulses from one nerve cell to another.. dopaminePronounced DOPE-uh-meen; a combination of carbon, hydrogen, nitrogen, and oxygen that acts as a neurotransmitter in the brain. is the neurotransmitter that acts on the part of the brain responsible for feeling pleasure, filtering incoming information, making choices, judging behavior, and deciding when and how to act.
NIDA researchers believe that obese people do not have enough receptors on their brains' nerve endings to grab on to dopamine and allow it to do its work. The decrease in dopamine receptors is apparently linked to a high BMI. The greater a person's BMI number, the fewer dopamine receptors they seem to have in their brains. NIDA Notes staff writer Robert Mathias quoted Dr. Nora Volkow as saying: "An individual who has low sensitivity to normal stimuli learns behaviors, such as abusing drugs or overeating, that will activate" those areas of the brain that "create a sense of wellbeing." The next step in this research is to determine if there are ways other than overeating or drug-taking that can stimulate the pleasure centers in the brains of these individuals.
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