DIET AND PHARMACEUTICAL TREATMENT
During the history of treating obesity with pharmaceuticals, there have been multiple drugs used. From amphetamines to other medications (like fenfluramine and dexfenfluramine) some have been abandoned because of their potential risk factors. There are also other commercial products with supposed anti-obesity effects (fiber, chitosan, etc) whose clinically efficacy have been heavily questioned.
Currently, based on the fact that obesity is rarely cured, the available treatments are palatable, and their effectiveness is prolonged during use and is generally part of a treatment plan in a form because, once the patient has given up, the weight usually returns. Any medication used to treat obesity should pass a series of strict criteria for safety and long-term effects. In general, for a medication to be effective in the treatment of obesity, it should influence energy in-take, energy use or both; it is also important to keep in mind that the use of a medication that only acts on one of these factors, (in-take or use of energy) usually fails in the long-term, due to the mechanism of the body to compensate for changes in metabolism.
Today, the decision to use pharmaceutical treatments is based on strict clinical criteria that are supported by an individual evaluation of potential risks and benefits of their use. However, it should always be managed under these strict criteria:
- They should not be used as an isolated treatment, rather combined with diet therapy, physical activity and psychological support.
- It can be indicated for patients with an IMC>30 kg/m2, or those with an IMC >27Kg/m2 if they are associated with comorbidities (diabetes, hypertension, sleep apnea syndrome, dyslipemia, etc.)
- They are contraindicated in children, pregnant or lactating women and, in the case of sibutramine, in patients with difficult to control hypertension or an unstable heart condition.
- While there are many pharmaceuticals in development or being researched, only two have been approved in Spain for the treatment of obesity: orlistat and sibutramine.
Orlistat
Orlistat is a derivative of lipstatine, produced by the bacteria Streptococus Toxitricini. It acts as an inhibitor of the pancreatic lipase, partially impeding hydrolysis and the absorption of fat in the diet without interfering with carbohydrates or proteins. It has been observed in studies that with one dose of 120mg three times a day (the normal dose used) the blockage in the absorption of fat is more than 30% of orally ingested lipids. It has also been demonstrated that after one year of treatment with orlistat and a hypercaloric conventional diet, weight-loss ranged from 9-10%, in comparison with the 4-6% lost with conventional diets alone. Following the same trend, the use of orlisat (for at least 6 months) with a diet provokes less recuperation of weight after the medication is stopped and is treated solely with diet. Other beneficial effects from the use of orlistat in the treatment of obesity are its relation to the capacity to reduce cholesterol levels and improve glucose metabolism (with a decrease in the progression of pre-diabetes and type 2 Mellitus diabetes).
The most frequent side effects are not serious and mainly affect the gastrointestinal area (and thus are also related to an unfulfilled diet as an there is an increase in ingested fat): urgency in bowel movements, an increase in number of bowel movements, oily discharge. These collateral effects decrease with time of use and rarely result in the need to suspend treatment.
The absorption of liposoluble vitamins (above all beta-carotene and vitamin E) can reduce, but the levels in the blood usually maintain normal levels.
The prescription of orlistat (commercialised in Spain with the name (Xenical 120 mg ®, by Roche Farma Laboratories) is exclusively used in accordance with orders of a doctor who is accustomed to dealing with issues of obesity and cannot be administered without a medical prescription. It should only be employed if a previously attempted diet has only produced a reduction of less than 2.5 Kg of weight in 4 consecutive weeks.
In Spain, one of the inconveniences of the use of orlistat is economic as, at the moment, it is a medication not economically financed by the National System of Health, meaning and elevated cost (95€ for one month of treatment).
Sibutramine
Sibutramine is a betaphenylamine that selectively inhibits the recapturing of noradrenaline and serotonin (related to tricyclic anti-depressants). Sibutramine produces significant weight-loss by inducing a lower level of energy ingestion by increasing the feeling of fullness and a decrease in appetite, as well as an increase in energy use.
The weight-loss achieved is maintained over a long period, with losses over one year of treatment of 13.9% in relation to the initial weight of the patient. It has also been shown to have a beneficial effect on the reduction of glucose, cholesterol, triglycerides and uric acid.
The principle adverse side effects are dryness of the mouth, insomnia and tiredness; there also exist the possibility of tachycardia and a small elevation in blood pressure, requiring the strict monitoring of both. The elevation of blood pressure and a bad tolerance of possible side effects may result in the need to stop this treatment. It should not be used on patients with psychiatric illness (including a past of bulimia or anorexia) or in conjunction with a treatment of anti-depressants, cardiac, renal or hepatic illnesses.
The prescription of Sibutramine (commercially known as Reductil 10 or 15 mg ®, from Abbot Laboratories) should be administered by a medical expert in the treatment of obesity, under frequent clinical control and only in those patients who have not been able to achieve or maintain a reduction of 5% from their initial weight over three months. It cannot be administered without a medical prescription.
In the same manner as orlistat, sibutramine is a medication not financed be the Spanish National System of Health, and for this reason it comes with a high cost paid solely by the patient (96-99€ for one month of treatment).