Drugs which reduce hunger are known as appetite suppressants
The simplest drugs in this category are those which increase the bulk of the materials in the stomach, generating a feeling of fullness that prevents further eating. These drugs include methylcellulose.
Drugs may work directly on the brain to suppress the appetite. The first drugs to be used clinically were amphetamines, such as dexamphetamine, which worked by increasing the amount of neurotransmitters norepinephrine and 5HT* produced by cells in the brain.
The hypothalamus controls food intake and balances the activities of these and the amphetamines shift the balance between them in the direction that reduces feeding. The amphetamines are no longer used for this purpose due to their tendency to stimulate the brain and cause addiction. Related drugs used were fenfluramine and dexfenfluramine, but both drugs were withdrawn because they disturbed the function of the valves in the heart which may have led to heart failure after many years of use.
The main drug recommended for obesity is which stimulates of norepinephrine and seems able to reduce appetite without producing addiction. Combinations of phentermine and fenfluramine are still obtainable, but illegally and are known as Phen/Fen drugs.
Orlistat is another drug that was introduced to treat obesity
In the intestine fatty substances (lipids) are broken down by enzymes, thus reducing lipases into smaller molecules which then can be absorbed across the intestine wall.Orlistat inhibits the activity of these enzymes, reducing the breakdown of fat and therefore, its absorption. The result is a reduced caloric intake, especially of fats leading to a gradual loss in weight.
The main problem with the drug however, is that some vitamins are dissolved in fat, so that reduction a reduction of fat absorption could lead to a deficiency of fat-soluble vitamins unless a supplement is taken. Other side-effects include the production of soft, fatty stools, flatus (wind) and incontinence.
Latest Anti –Obesity Drugs:
Obesity has spiraled in the US, and the FDA has approved a new drug to tackle the epidemic. The FDA is extremely cautious regarding the approval of drugs but felt that United States needed a drug to tackle obesity as they were in short supply.
The new obesity drug – Belviq is also an appetite suppressor and worked very well in trials. However candidates for the drug will be only considered the treatment if they have a BMI (Body Mass Index) of no less than 30.