Medicines Theophylline

After the nucleic acid purines adenine and guanine, the next most prominent purine in our everyday lives is probably caffeine. Caffeine, in the form of beverages such as tea, coffee, and cola, is one of the most widely consumed and socially accepted natural stimulants. Closely related structurally are theobromine and theophylline. Theobromine is a major constituent of cocoa, and related chocolate products. Caffeine is also used medicinally,... 

Theophylline is found in coffee and in tea in very small amounts, but it has a stronger effect on the heart and breathing than does CF. Along with CF, TP is used as a medicine to treat emphysema and bronchitis (254,255). Caffeine and TP inhibit cAMP phosphodiesterase. In their presence the effects of cAMP, and thus the stimulatory effects of the hormones that lead to its production, are prolonged and intensified. 

Caffeine is used medicinally as a CNS stimulant, usually combined with another therapeutic agent, as in compound analgesic preparations. Theobromine is of value as a diuretic and smooth muscle relaxant, but is not now routinely used. Theophylline is an important smooth muscle relaxant for relief of bronchospasm, and is frequently dispensed in slow-release formulations to reduce side-effects. It is also available as aminophylline (a more soluble preparation containing theophylline with ethylenediamine) and choline theophyllinate (theophylline and choline). The alkaloids may be isolated from natural sources, or obtained by total or partial synthesis. 

Weinberger M and Hendeles L (1996) Theophylline in asthma. New England Journal of Medicine 334 1380-1388. 

The general properties of the methylxanthines (theophylline, caffeine) are discussed elsewhere (see p. 194). Their mild diuretic action probably depends in part on smooth muscle relaxation in the afferent arteriolar bed increasing renal blood flow, and in part on a direct inhibitory effect on salt reabsorption in the proximal tubule. Their uses in medicine depend on other properties. 

The Polish proprietary medicine Dehydrit is described in Gehe s Codex (3rd supplement, 1950) as the sodium salt of o-[(3-hydroxymercuri-2-methoxypropyl) carbamyl]phenoxyacetic acid dissolved in aqueous itheophylline solution. This preparation is known in the U. S. Pharmacopeia as Mersalyl and theophylline injection, and in the U. S. Dispensatory (page 700, 24th edition) the pharmacist is informed of the United States equivalent in the form of Salyrgan-Theophylline Ampuls (Winthrop). 

Emerman CL, Devlin C, and Connors AF (1990) Risk of toxicity in patients with elevated theophylline levels. Annals of Emergency Medicine 19 643-648. 

Olson KR, Benowitz NL, and Woo OF (1985) Theophylline overdose Acute single ingestion versus chronic repeated overmedication. American Journal of Emergency Medicine 3 386-394. 

Committee on Safety of Medicines/Medicines Control Agency. Fluvoxamine increases plasma theophylline levels. Current Problems (1994) 20, 12. 

Structurally theophylline resembles caffeine however, it lacks the methyl group in the five-carbon ring. It occurs naturally in the tea plant, but it is synthesised from caffeine for use in medicine. The... 

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