Overweight in Adolescence: Can Therapeutic Drugs Help?

Posted on Tuesday, April 3rd, 2007

Childhood and adolescent obesity causes diseases such diabetes, high blood lipids and high blood pressure. It also increases the risk for these diseases along with cardiovascular complications in adulthood.

These serious complications explain the amount of interest and effort geared towards the prevention and treatment of adolescent obesity. Because of this critical period in a person’s development, much assessment should be made by clinicians in order to determine specifically which individuals should be treated and how.
The Society of Adolescent Medicine states that “…adolescent weight management programs should support overall health as well as optimal growth and development”.

The treatment of choice for childhood and adolescent weight problems is the conventional behavioral and lifestyle modifications. In those cases where the child/adolescent is severely overweight and conventional weight reducing programs are not working, pediatricians and health care givers are turning to therapeutic drugs –in conjunction with behavioral and lifestyle modifications– in hopes that it will be beneficial.

Though few drugs are FDA approved for the treatment of obesity in adults mainly Sibutramine (trade name Meridia) and Orlistat (trade name Xenical). So far, the only drug currently FDA approved for treatment of adolescent obesity is Orlistat. Orlistat is a digestive inhibitor; it reduces the amount of dietary fat absorbed in the gut and thus decreases calorie absorption, leading to weight loss. Studies on efficacy and safety of Orlistat in obese adolescents lead to the approval of its use in 12-18 year old adolescents in 2003 in the US and later in the European Union. The study results showed that patients treated with Orlistat plus diet had a significantly reduced BMI compared with those who were on the dietary plan alone.
The specific conditions for Orlistat prescription in adolescents are:

• At least 12 years of age.
• BMI more than two units above the 95th percentile.

Some physicians are even more restrictive on the use of drugs, they reserve drug therapy for very obese patients whose behavioral therapy fails to work alone. In addition, one must keep in mind the other conditions for prescription of this drug that apply to both adults and adolescents, namely this drug should be prescribed by the physician as a conjunct to a behavioral weight loss plan consisting of a low-fat, reduced caloric diet and a physical activity regimen. Orlistat should NEVER be prescribed or taken as a sole treatment option.
Orlistat has reported side effects which are shared between both adults and adolescents taking this drug. Patients taking Orlistat may experience:

• Gas with oily discharge,
• Increased bowel movement
• Fecal incontinence.

A major point of concern in this digestive inhibitor drug is the potential decrease in fat soluble vitamins’ absorption, which may lead to some vitamin deficiencies, a major point of concern especially in the growing adolescent. The FDA has strongly suggested the inclusion of a multivitamin in the product packaging for use in the adolescent population. The conclusion is that adolescents taking this drug SHOULD take a multivitamin supplement.
It is worth noting that NO clinical studies addressed the long-term effects of Orlistat in adolescence. The longest intervention study was for one-year and no follow-up was done afterwards. In a recent editorial in the Annals of Internal Medicine, Dr. Dietz suggested that clinicians should carefully weigh the decision to prescribe drug therapy for the treatment of adolescent obesity, because the long-term effects of drug therapy in children and adolescents are unknown at this time.
Given this information and lack of sufficient data, more regulations and guidelines are needed in the area of pharmacotherapy for adolescent obesity. In a recent paper addressing drug therapy in childhood obesity, Dr. Molnar states:

“In extremely obese adolescents with obesity-related comorbidities being resistant to conventional weight-reducing programs… a rationale for pharmacological treatment could easily be established, but in the majority of cases the indication of drug therapy, the evaluation of benefit/risk ratio is much more difficult.”

Du to this lack on universal guidelines regarding the issue of drug treatment for children/adolescent obesity, it is to set guidelines addressingthe following points:

• Indications of treatment
• Who should indicate and supervise the treatment (obesity expert or general practitioner)
• Duration of treatment
• Safety measures

A final note on the use of Orlistat in adolescents is the ongoing FDA approval decision on the release of Orlistat as an over-the-counter drug. The North American Association for the Study of Obesity(NAASO) has reviewed that decision and expressed the following concerns –stated verbatum:

• Safety concerns: Orlistat has a strong safety record. There is a major need for a multiple vitamin supplement (fat soluble vitamins) and there is some interference with absorption of other lipid soluble drugs. It is essential that any OTC bottle clearly note very carefully both concerns and strongly recommend that multiple vitamin supplements be taken with Orlistat OTC.
• Potential for abuse: As an OTC drug, there is concern that this availability will lead to abuse by people who are suffering from eating disorders. Furthermore, this drug is only advisable as an adjunct to individuals engaged in an active weight loss program that focuses on a healthy diet, caloric restriction, and increased physical activity. The 60 mg dose of Orlistat will be less effective than the currently prescribed higher dose.
• OTC availability will most likely increase significantly Orlistat usage since doctors uncommonly prescribe anti-obesity drugs. The FDA must require a careful monitoring system be established to study the uses and abuse of Orlistat as an OTC drug.
• Age limitations on Orlistat use: Orlistat must be limited to persons aged 14 and older. The research seems to indicate that trials have been done with adolescents and there were no serious problems. This research found that “Orlistat, in combination with diet, exercise, and behavior modification, improves weight management in obese adolescents”(Chanoine, Hampl et al. 2005). Again there is concern that normal or even anorexic and bulimic adolescents will use and abuse this drug.