Naslov
Kofein
(Caffeine)

Autori
Zorc, Branka ; Grga, Divna

Izvornik
Farmaceutski glasnik : glasilo Hrvatskog farmaceutskog društva (0014-8202) 54 (1998), 12; 437-441

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, stručni

Ključne riječi
kofein; psihostimulans; napitci; zlouporaba
(caffeine; psychostimulant; drinks; drug abuse)

Sažetak
Caffeine is the most popular, widely consumed, legal, and socially acceptable psychoactive drug in the world. It is found in coffee, tea, cola drinks, chocolate, and cocoa. Caffeine is a part of many analgesic combination products and it is abused in some sport disciplines.Taken orally, caffeine is rapidly and completely absorbed. It is equally distributed throughout all the water in the body. Most caffeine is metabolized by the liver before it is excreted by the kidneys. The main metabolites are partially demethylated and oxidized derivatives. Caffeine is an effective psychostimulant. Behavioral effects of caffeine include increased mental alertness, a faster and clearer flow of thought, wakefulness, and restlessness. In the usual doses of 50-200 mg caffeine is active in the cortex. In higher doses stimulates the vasomotor and respiratory centers. The spinal cord stimulation occurs only in toxic doses. It has a slight stimulant action on the heart, increasing cardiac contractility and output and dilating the coronary arteries. It constricts cerebral blood vessels. The beneficial effect of caffeine for vasomotor headache is due to this vasoconstrictive effect. In addition, caffeine causes bronchial relaxation, increases secretion of gastric acid, and increases urine output. All its actions are result of nonselective adenosine receptors inhibition. Chronic use of caffeine is associated with habituation and tolerance and discontinuation may produce a withdrawal syndrome. Caffeinism is a clinical syndrome produced by the overuse of caffeine. It is characterized by both CNS and peripheral symptoms: insomnia, anxiety, tachycardia, hypertension, cardiac arrhythmias and gastrointestinal disturbances. A conservative view is that caffeine should be used in moderation by people who are at risk for heart disease and not used at all during pregnancy, breast-feeding and even before conception.

Izvorni jezik
Hrvatski

Znanstvena područja
Kemija

POVEZANOST RADA