Rate of Delivery

The concentrations of the drug at the desired sites and at the sites of toxicity within the respiratory tract will depend on the balance of the drug supply and clearance rates at these sites [37]. We may speculate that this is one of the reasons for the higher doses required for the delivery of topical medications by nebulizers (typically over 10-25 min) vs. metered-dose inhalers or dry powder inhalers that deliver the medication in one or two breaths. There is little doubt that prolonged inhalation reduces the patient's enthusiasm for the therapy. It is therefore appropriate to evaluate nebulizers in terms of their useful output, that is, the dose of the therapeutic or diagnostic agent delivered in the desired aerodynamic size range per unit time [145].

For systemic administration of readily absorbed molecules, the rate of delivery may be the rate-limiting step. This is evidenced with small molecules, such as morphine, whose absorption rate following deep lung delivery is practically indistinguishable from that after intravenous injection [146].

Diabetes 2

Diabetes 2

Diabetes is a disease that affects the way your body uses food. Normally, your body converts sugars, starches and other foods into a form of sugar called glucose. Your body uses glucose for fuel. The cells receive the glucose through the bloodstream. They then use insulin a hormone made by the pancreas to absorb the glucose, convert it into energy, and either use it or store it for later use. Learn more...

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