Extended-release dosage forms limitations

Unlike the majority of controlled-, sustained-, or extended-release systems in use, the extent of response in the lungs will be limited by intrinsic clearance mechanisms [110]. It will be surprising, but not unwelcome, if any deposited dosage form can extend the effective duration of action much beyond a day. Twenty-four hours would, in fact, be a significant achievement. 

Table 11.1 Advantages and limitations of a drug formulated into an extended release (ER) dosage form Clinical advantages...

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