Velázquez AY, Nava OAA

Language: Spanish
References: 11
Page: 148-153
PDF size: 61.67 Kb.

ABSTRACT

From birth, the physiological changes that take place during the development and growth of the human being are multiple and very varied. Dosage in children would require adjustments according to the age, severity of the disease, and even to sex differences, especially during the adolescence when hormonal changes could influence certain enzymatic systems. The election among the different modalities from administration of medicines depends on multiple clinical and therapeutic aspects. Solid or gel oral formulations, under the action of the gastric juice, release the drug allowing it to be absorbed in the gut. Once in blood, the drug is distributed, metabolized and eliminated. This sequence of processes is known as LADME. The amount of inalterable drug that arrives at the general circulation knows like bioavailability. The drugs administered by extravascular routes must cross several cellular membranes with certain semipermeable characteristics before reaching the general circulation. The speed at which drug is absorbed and its bioavailability depends on its own physical and chemical characteristics as well as on physiological processes and pathological alterations.

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