Pharmacokinetic Comparison
"Several factors affect the systemic absorption of a drug following parenteral injection. Among the most important factors is blood circulation to the site of absorption (Wilkinson, 2001).
Increased blood flow caused by local application of heat or massage will increase the absorption rate. Conversely, decreased blood flow caused by various disease states or vasoconstrictive agents can decrease the absorption rate. Furthermore, the surface type exposed to drug (for example, stomach, intestine, airway/lungs, skin, subcutaneous tissue, muscle) influences where absorption occurs (Wilkinson, 2001). This area of absorption is determined by the route of drug administration."
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