Background: Obesity represents the second preventable mortality cause worldwide,
and is very often associated with type 2 diabetes mellitus (T2DM). The first line treatment
is lifestyle modification to weight-loss, but for those who fail to achieve the goal or have
difficulty in maintaining achieved results, pharmacological treatment is needed. Few drugs are
available today, because of their side effects.
Objective: We aim to review actual pharmacological management of obese patients, highlighting
differences between Food and Drug Administration – and European Medicine
Agency-approved molecules, and pointing out self-medications readily obtainable and widely
Method: Papers on obesity, weight loss, pharmacotherapy, self- medication, and diet-aid
products were selected using Medline. Research articles, systematic reviews, clinical trials
and meta-analyses were screened.
Results: Anti-obesity drugs with central mechanisms, such as phentermine and lorcaserin, are
available in USA, but not in Europe. Phentermine/topiramate and naltrexone/bupropion combinations
are now available, even though the former is still under investigation from EMA.
Orlistat, with peripheral mechanisms, represents the only drug approved for weight reduction
in adolescents. Liraglutide has been approved at higher dose for obesity. Anti-obesity drugs,
readily obtainable from the internet, include crude-drug products and supplements for which
there is often a lack of compliance to national regulatory standards.
Conclusions: Mechanisms of weight loss drugs include the reduction of energy intake or the
increase in energy expenditure and sense of satiety as well as the decrease of hunger or the
reduction in calories absorption. Few drugs are approved, and differences exist between USA
and Europe. Moreover, herbal medicines and supplements often sold on the internet and
widely used by obese patients, present a risk of adverse effects.