Obesity is considered the most concerning and blatantly visible--yet most 
neglected--public health problem by the WHO. The steadily increasing number of 
overweight and obese people has reached 2.3 billion and 700 million worldwide, 
respectively. Obesity is a complex condition, one that presents serious health 
risks with respect to type 2 diabetes, ischemic heart disease, and hypertension, 
therefore controlling the global obesity epidemic decreases not only health 
problems, but also expenditure. The underlying cause of obesity is a metabolic 
disorder of genetic, central nervous system or endocrine etiology that manifests 
in increased nutritional intake and/or decreased physical activity ultimately 
leading to excessive lipogenesis. The natural treatment of obesity, that is 
often advised, is comprised of healthy lifestyle choices, namely low-calorie 
diet and exercise. However, the pharmaceutic treatment of obesity is just as 
important; having a better compliance rate, anti-obesity drugs also improve 
quality of life and patient-care outcome concerning accompanying diseases. In 
most countries only one drug is currently available against obesity: orlistat, 
which is a specific and irreversible lipase inhibitor. One of the reasons for 
the scarce number of anti-obesity drugs is the complex pathomechanism involved 
in obesity. Interference with the intricate biochemical processes that govern 
alimentation may lead to widespread adverse effects. The advances of the field 
however, have prompted novel drug leads. In the past few years FDA has approved 
new drugs for the treatment of obesity, recently liraglutide in 2014. The 
approval of drug combinations, such as phentermine/topiramate and 
bupropion/naltrexone are also noteworthy, the components of which have been 
previously approved, but not necessarily for obesity as main indication. 
Furthermore, there are many anti-obesity drug candidates currently in clinical 
phase trials, with promisingly modest adverse effect profiles; hence the 
expansion of the anti-obesity agents in the near future can be foreseen. The 
present work summarizes the central and peripheral regulatory pathways of energy 
consumption, nutrition, and appetite. The possible drug targets, the currently 
available and novel anti-obesity agents, and the new trends in obesity research 
are also discussed.