Why are Central α2-agonists considered secondary line anti-hypertensive agents?

Central α2-agonists, such as clonidine and guanfacine, are classified as secondary line anti-hypertensive agents primarily because of their high incidence of adverse reactions. While they can be effective in lowering blood pressure, their side effects can be significant and often limit their use as first-line treatments. Common side effects include sedation, dry mouth, and the potential for rebound hypertension upon discontinuation.

These adverse reactions can affect patient compliance and contribute to the reluctance of healthcare providers to prescribe them as initial therapy options. As a result, they are typically reserved for cases where other first-line agents, such as thiazide diuretics, ACE inhibitors, or calcium channel blockers, are ineffective or unsuitable.

Considering the other options, it is not that these agents have low efficacy compared to other treatments; rather, their safety profile is the main concern. Also, their availability in pharmacies is generally adequate, and they do not inherently increase the risk of hypertension when used appropriately. Thus, the primary reason for their classification as secondary line agents is indeed related to the frequency and severity of their adverse effects.