Appetite suppressants, anorectic or anorexigenic drugs affect appetite and reduce food intake.
Anorectics have been used to treat obesity for more than 50 years, but disputes about their effectiveness and safety are still ongoing.
Given that more than 35% of adult Americans are obese, there is a great need for timely diagnosis and treatment of this disease, which has reached epidemic proportions. Doctors should recommend their patients to use anorectics, even those who do not consider obesity as a big problem or disease.
Anorectics are prescribed to patients who cannot lose enough weight only by means of intensive lifestyle intervention. The main purpose of using anorectics is weight loss by 5-10% of the original body mass.
Secondary goals of weight management can be:
- Improvement quality of life
- Delay or prevention of development of type 2 diabetes
- Decrease in risks of cardiovascular diseases
- Prevention of other negative consequences of obesity.
Prescription anorectics do not always act as expected, for example, cause side effects. Therefore, weight reduction and other health benefit should be compared with adverse reactions.
When choosing anorectics, it is necessary to pay attention to their benefit-risk balance. Effectiveness, and, most importantly, safety of treating overweight or obesity depends namely on this balance.
At present, several safe anorectics are sold at the American pharmacies, including:
All these drugs underwent numerous clinical trials, after which they were approved by the FDA.
The fact that anorectics were approved by the FDA should be a guarantee of their effectiveness and safety. Nevertheless, there are several examples of how anorectics were first approved by the FDA used to treat patients with obesity for a long time, but then withdrawn from the market.
A list of such anorectics includes:
Sales were discontinued because of negative benefit-risk balance. Besides weight loss, such drugs should reduce risk of cardiovascular diseases. Instead of this, they often caused myocardial infarction, stroke and other forms of heart diseases and cardiovascular system.
It should be noted that prescription anorectics currently approved by the FDA might also have a negative effect on the heart work and cardiovascular system. However, such drugs bring more benefit than harm, at least for most people, and therefore they are used to treat overweight or obesity.
A list of cardiovascular side effects of most anorectics includes increased blood pressure, tachycardia, palpitations, precordial pain and angina pectoris. To prevent cardiovascular risks, such drugs should not be used in patients with cerebrovascular diseases, moderate or severe hypertension, arterial pulmonary hypertension and severe heart diseases.
An exception is Lorcaserin drug. It does not cause cardiovascular side effects, has virtually no contraindications (except pregnancy) and therefore is safer than other anorectics are.
Despite a good safety profile, Lorcaserin is not the most commonly used anorectic. This is related to the fact that Lorcaserin does not greatly suppress appetite and therefore modestly reduces body weight.
Today, Phentermine is the most widely used prescription anorectic in the USA. It is used more often than all other appetite suppressants. Phentermine came into the market in 1959 and was the first appetite suppressant, effectiveness and safety of which were evaluated by the FDA.
Phentermine and other anorectics are usually prescribed as a short-term treatment of overweight or obesity (up to 12 weeks). If the patient has lost more than 5% of his body weight during this time and continues to steadily lose it, the treatment can be continued.
According to one of the clinical trials, patients, who took Phentermine for 2 to 24 weeks, have lost at the average 6.5 kg of body weight. Approximately the same or worse results in weight loss can be expected when using other anorectics.
A disadvantage of prescription anorectics is a gradual reduction of safety and efficacy. For example, prolonged use of Phentermine may result in physical or psychological addiction.
The maximum appetite suppression occurs in the first few weeks of obesity treatment and then decreases.
In order to increase anorexigenic effect again, patients often begin to exceed the recommended dose and, as a result, the treatment safety decreases.
Benefit-risks balance of anorectic drugs decreases over time so appropriateness of pharmacotherapy of obesity should be justified. Only proper use of the recommended doses of anorectics and gradual reduction of body weight have a positive effect on function of all body systems and improve quality of life.