Biomaterial Database

Absorption properties of two theophylline sustained-release products in smokers. 1984

R Miller, and M Rheeders

The absorption of theophylline from two commercial products labelled as having sustained-release properties (Theo-dur; Rio-Ethicals; and Euphyllin Retard; Byk-Gulden) was compared with that of a solution of theophylline (Alcophyllin syrup; Propan-Lipworth) in a multiple-dose study in smokers. As regards bioavailability, results for Theo-dur and Euphyllin Retard tables were statistically indistinguishable from that for the standard, but both products showed significantly slower absorption as reflected by longer times to attain peak concentration and lower peak concentrations. Theo-dur exhibits better sustained-release properties than Euphyllin Retard as judged from the peak/trough ratio and the persistence of concentrations from 6 hours to 12 hours after administration. Assuming linear pharmacokinetics and projecting to therapeutic doses, Euphyllin Retard results in much wider fluctuations between peak and trough concentrations (18,9 and 9,8 micrograms/ml) than does Theo-dur (13,8 and 10,2 micrograms/ml), and this product might be more acceptable in smokers if given in an 8-hourly schedule.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008297	Male		Males
D008875	Middle Aged	An adult aged 45 - 64 years.	Middle Age
D003692	Delayed-Action Preparations	Dosage forms of a drug that act over a period of time by controlled-release processes or technology.	Controlled Release Formulation,Controlled-Release Formulation,Controlled-Release Preparation,Delayed-Action Preparation,Depot Preparation,Depot Preparations,Extended Release Formulation,Extended Release Preparation,Prolonged-Action Preparation,Prolonged-Action Preparations,Sustained Release Formulation,Sustained-Release Preparation,Sustained-Release Preparations,Timed-Release Preparation,Timed-Release Preparations,Controlled-Release Formulations,Controlled-Release Preparations,Extended Release Formulations,Extended Release Preparations,Slow Release Formulation,Sustained Release Formulations,Controlled Release Formulations,Controlled Release Preparation,Controlled Release Preparations,Delayed Action Preparation,Delayed Action Preparations,Formulation, Controlled Release,Formulations, Controlled Release,Prolonged Action Preparation,Release Formulation, Controlled,Release Formulations, Controlled,Sustained Release Preparation,Timed Release Preparation,Timed Release Preparations
D005260	Female		Females
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000042	Absorption	The physical or physiological processes by which substances, tissue, cells, etc. take up or take in other substances or energy.
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults
D001682	Biological Availability	The extent to which the active ingredient of a drug dosage form becomes available at the site of drug action or in a biological medium believed to reflect accessibility to a site of action.	Availability Equivalency,Bioavailability,Physiologic Availability,Availability, Biologic,Availability, Biological,Availability, Physiologic,Biologic Availability,Availabilities, Biologic,Availabilities, Biological,Availabilities, Physiologic,Availability Equivalencies,Bioavailabilities,Biologic Availabilities,Biological Availabilities,Equivalencies, Availability,Equivalency, Availability,Physiologic Availabilities
D012907	Smoking	Willful or deliberate act of inhaling and exhaling SMOKE from burning substances or agents held by hand.	Smoking Behaviors,Smoking Habit,Behavior, Smoking,Behaviors, Smoking,Habit, Smoking,Habits, Smoking,Smoking Behavior,Smoking Habits