Phentermine Hydrochloride (HCL), commonly referred to as simply Phentermine is a prescription drug for weight loss supplements. The drug is available in pill form and is usually prescribed for obese individuals for short term use. Although the pill acts as an appetite suppressant, doctors recommend that phentermine is used in combination with other more natural weight-loss solutions, diet and exercise.
Phentermine is a member of sympathomimetic family of drugs. These appetite suppressants works by stimulating the hypothalamus, found a gland in the brain. The hypothalamus is responsible for regulating a number of autonomic nervous system functions, including appetite.
When phentermine enters the body, it triggers certain neurotransmitters (known as catecholamines) which sends a signal to the hypothalamus to limit hunger. Specific neurotransmitters involved include dopamine, epinephrine and norepinephrine.
Phentermine is partly prescribed for short-term use because patients sometimes build up a tolerance to the drug. This tolerance can occur in as quickly as a few weeks. When tolerance sets in, phentermine ability to elicit neurotransmitter greatly reduced. As a result, remain unaffected hypothalamus and hunger continues. Again, phentermine intended as a short-term solution to ease the transition to a reduced caloric intake and / or more physical lifestyle.