Systemic delivery of antihypertensive drugs via skin.

Hypertension is a chronic disease with one of the highest chances of causing death, and long-term treatment is required. The antihypertensive drugs used in the treatment are generally administered orally. The limitations of the oral route make transdermal delivery of drugs more attractive. The transdermal route offers numerous advantages including avoidance of systemic first-pass metabolism and high patient compliance. The transdermal therapeutic systems, popularly known as 'patches', deliver drugs across the skin with a constant release rate. However, skin is a unique membrane having excellent barrier properties. Either chemical enhancers or physical methods such as iontophoresis and electroporation have been used to provide effective plasma drug concentrations. This review article focuses on the approaches to enhance skin permeability of antihypertensive drugs for the optimization of transdermal therapeutic systems of these drugs and the research studies intended for the optimization of transdermal dosage forms of antihypertensive drugs are summarized.