Which route involves absorption through the skin from a patch?

Which route involves absorption through the skin from a patch?

• A. Inhalation
• B. Rectal administration
• C. Transdermal
• D. Snorting

Answer: (C)

Absorption through the skin from a patch is the transdermal route. When a patch is applied, the drug slowly diffuses from the patch through the skin’s layers into small blood vessels, delivering the medicine into the bloodstream for a controlled, steady release. This route is designed to provide sustained drug levels and to avoid much of the gastrointestinal tract and first-pass metabolism in the liver. For effective transdermal delivery, the drug generally needs to be lipophilic and of suitable size to penetrate the skin. Inhalation delivers drugs via the lungs, quickly entering the bloodstream through the alveolar membranes. Rectal administration uses the rectal mucosa, and intranasal (snorting) uses the nasal mucosa. These routes are not associated with a patch on the skin, which is why the skin-absorption route is the correct description here.

Absorption through the skin from a patch is the transdermal route. When a patch is applied, the drug slowly diffuses from the patch through the skin’s layers into small blood vessels, delivering the medicine into the bloodstream for a controlled, steady release. This route is designed to provide sustained drug levels and to avoid much of the gastrointestinal tract and first-pass metabolism in the liver. For effective transdermal delivery, the drug generally needs to be lipophilic and of suitable size to penetrate the skin.

Inhalation delivers drugs via the lungs, quickly entering the bloodstream through the alveolar membranes. Rectal administration uses the rectal mucosa, and intranasal (snorting) uses the nasal mucosa. These routes are not associated with a patch on the skin, which is why the skin-absorption route is the correct description here.