History, pharmacology, and toxicology of caffeine and caffeine-containing beverages
1987
McMurtrey, J.J. | Sherwin, R.
Extract: Caffeine-containing beverages have a very old history of usage. They are derived from natural products and as such contain literally hundreds of other substances. Coffee consumption has been decreasing, while decaffeinated coffee, tea, and soft drink consumption has recently been increasing. Most of the pharmacologic effects of low doses of caffeine are attributable to interaction with adenine receptors. Caffeine increases myocardial contractility and conduction velocity, while it has biphasic effects on heart rate and blood pressure levels. At high rates of consumption, however, tolerance to these effects is nearly complete. In animals caffeine enhances gastric acid secretion and ulcerogenic effects, but this relationship has never been examined in human subjects in controlled studies. Caffeine has been shown to stimulate the pituitary adrenal axis at concentrations encountered by human subjects. Caffeine may be lethal, with 3.2 g as the lowest reported fatal dose. Birth defects and mutations can also be produced in animals at toxic and lethal dose ranges, but not at doses normally consumed. The related methylxanthine, theophylline, is frequently used therapeutically to treat asthma and obstructive pulmonary disease. Caffeine also has medical use in neonatal apnea and atopic dermatitis.(author)
Show more [+] Less [-]AGROVOC Keywords
Bibliographic information
This bibliographic record has been provided by National Agricultural Library