Central nervous system phentermine

The p-chloro analog of phentermine has much the same activity as the parent compound, with perhaps a somewhat decreased activity on the central nervous system. Alkylation of p-chloro-benzyl chloride with the carbanion obtained from treatment of 2-nitropropane with strong base affords the compound containing the required carbon skeleton (74). Catalytic reduction of the nitro group yields chlorphentermine (75). ... 

Phentermine decreases food intake, and hence weight, by increasing norepinephrine and dopamine release in the central nervous system. This drug is indicated for short-term use—no more than a few weeks—in addition to lifestyle modifications in obese patients with a BMI of 30 kg/m2 or greater or a BMI of 27 kg/m2" or greater in the presence of other risk factors.38... 

Older drugs still available in some countries include phenylpropanolamine, benzphetamine, amphetamine, methamphetamine, phentermine, diethylpropion, mazindol, and phendimetrazine. These drugs are all amphetamine mimics and are central nervous system appetite suppressants they are generally helpful only during the first few weeks of therapy. Their toxicity is significant and includes hypertension (with a risk of cerebral hemorrhage) and addiction liability. 

The diet pills developed to replace amphetamines became known as anorectics or appetite suppressants and are central nervous system stimulants. The FDA approved phentermine in 1959, fenfluramine in 1973, and dexfenfluramine in 1996. 

Amphetamine stimulates the central nervous system, which suppresses the appetite. Most diet pills are sympathomimetics. They are similar to amphetamines, but are less powerful and have less potential for addiction. The sympathomimetics are benzphetamine, diethylpropion, mazindol, methamphetamine, phendimetrazine, phentermine, and sibutramine. 

Phentermine is a central nervous system stimulant that can increase brain dopamine concentrations and has a structure similar to amfetamine. 

With phentermine, adverse effects due to stimulation of the central nervous system are less than with dexamphetamine, although in one study withdrawal because of adverse effects was as high as 16 of 177 patients (9%) 2 of 13 healthy young volunteers withdrew because of unacceptable stimulation (83). 

Some drugs that act primarily on the central nervous system are diseussed under this category, namely flurothyl, mazindol, phentermine and methylphenidate hydrochloride. 

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