This paper explains the path of a sedative through the human gastrointestinal tract. An account is given on effects of the drug. The account analyzes the target and non-targeted organs as it goes through different phases from absorption, distribution, metabolism and its eventual excretion.
Pharmacodynamics is defined as the study of how a drug locates, interacts and affects target organs or tissues while pharmacokinetics is the study of how a body handles drugs through a process called drug action. Pharmacokinetics follows the four phases of digestion mainly absorption, distribution, metabolism and excretion. Absorption occurs when the drug is ingested. This is the point where the drug enters into the bloodstream and travels towards its target organ. Metabolism is the interaction of the drug with the body’s systemic processes and its transition from an agent to an effect. Excretion is the removal of the toxic wastes emanating from the drug (Dressman, 2000).
Oral administration of medications is described as the most common route for drugs. Once the drug enters the bloodstream it is subject to biological and physiochemical factors. The dosage form of the drugs influences the rate of absorption; solutions are absorbed faster and coated tablets are absorbed slowest (Dressman, 2000).
Absorption can occur in two ways: buccal administration, where medicine is placed between the gums and cheeks or sublingual administration where the drug is placed under the tongue to enhance absorption. This takes more time. Absorption of the oral drug is affected by differences in PH, mucous secretions, blood circulation, bile and the nature of the surface of the epithelial walls. The oral mucosa is thin and highly vascularized for efficient absorption, but its contact with the drug is too brief.
The stomach has a larger surface area, which is richly vascularized. Its thick mucus layer hinders gastric emptying. This is the reason why medicating on an empty stomach speeds up absorption. The absorption of drugs known as parasympatholytic affects the transmission of impulses reducing the intake of other drugs. Poor soluble drugs like Griseofulvin are absorbed more rapidly when ingested with food while a drug like Penicillin G’s absorption rate is the opposite (Dressman, 2000).
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