Relative lung and systemic bioavailability of sodium cromoglycate inhaled products using urinary drug excretion post

Osama Aswania1, Henry Chrystyn

  • 1School of Pharmacy, University of Bradford, Bradford BD7 1DP, UK.

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Factors Influencing Drug Absorption: Presystemic Elimination

The pharmacokinetic journey of oral drugs begins with a crucial first pass through the hepatic portal system, called the first-pass effect. This first pass significantly impacts bioavailability — the proportion of a drug that enters systemic circulation and is available for therapeutic action. The primary route sees the drug absorbed by intestinal membranes and then shunted to the liver via the hepatic portal vein. Here, pre-systemic elimination occurs as drugs face metabolism or biliary...
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Non-Oral Extravascular Drug Absorption Routes

Non-oral extravascular routes, which encompass sublingual, buccal, topical, intramuscular, and inhalation methods, primarily utilize passive diffusion to transport drugs into the systemic circulation. The absorption rates and effectiveness of these routes depend on the drug's physicochemical properties, as well as the patient's anatomical and pathophysiological state.
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Drug Excretion: Pulmonary and Glandular Routes

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