All of the following are advantages of transdermal drug delivery systems EXCEPT:
Transdermal route is employed for highly lipid soluble drugs that can traverse intact skin. The size of the pores in transdermal patch is adjusted to produce a uniform and smooth absorption of the drug. This will thus, produce a delayed and smaller peak in the plasma concentration. As the drug is going directly in the bloodstream, first pass metabolism is avoided. Eg : Transdermal patch- Rotigotine is used in Parkinson disease
They produce high peak plasma concentration of the drug
They produce smooth and nonfluctuating plasma concentration of the drug
They minimize inter-individual variations in the achieved plasma drug concentration
They avoid hepatic first pass metabolism of the drug
Pharmacokinetics