Drug therapy is not a primary form of treatment for overweight and obesity, as only a change in diet and exercise can permanently reduce body weight. Drugs are only used if no or insufficient weight loss is achieved through lifestyle changes. A drug therapy should always be carried out in combination with a basic program consisting of nutrition, exercise and behavioural therapy.
For patients with a BMI ≥ 28 kg/m² and additional risk factors or already existing secondary diseases of obesity or a BMI ≥ 30 kg/m² a drug therapy can be considered under the following conditions:
- weight loss of < 5% of initial weight within six months under basic therapy
- weight gain of > 5 % of the initial weight within six months after a phase of weight reduction
Continuation of the drug treatment should only be continued if weight loss of at least 2 kg has been achieved within the first four weeks.
The current guideline "Prevention and Therapy of Obesity" of the German Obesity Society (as of 2014) only recommends the drug "Orlistat" for the drug treatment of obesity.
Orlistat
Orlistat is approved from a BMI ≥ 28 kg/m² for the supportive treatment of obesity. It inhibits lipases (fat-splitting enzymes) in the gastrointestinal tract and thereby reduces fat absorption. The maximum dosage of orlistat is 120 mg 3x daily with the main meals.
Because of insufficient digestion of fat in the gastrointestinal tract, orlistat can lead to abdominal cramps, flatulence, increased stool urge and diarrhoea. The absorption of fat-soluble vitamins by the preparation is also reduced.
The weight-reducing effect of orlistat should not be overestimated. In a study conducted over 4 years, the weight loss with simultaneous lifestyle intervention was 10.6 kg after 1 year and 5.8 kg after 4 years.
Bilbiography sources:
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