What is a noted adverse reaction from decongestants?

Decongestants are agents commonly used to relieve nasal congestion by narrowing the blood vessels in the nasal passages. This vasoconstriction can lead to increased blood pressure as a secondary effect. The mechanism primarily involves stimulation of the alpha-1 adrenergic receptors, which causes constriction of blood vessels and subsequently elevates blood pressure.

It is important to monitor patients who are taking decongestants, especially those with pre-existing hypertension or cardiovascular conditions, as their blood pressure may rise significantly. In this context, the increased blood pressure is a well-documented and notable adverse reaction associated with the use of decongestants.

The other avenues of potential adverse effects such as feeling increased energy or experiencing nausea can occur, but they are not as prominent or directly linked to the physiological effects of decongestants in relation to their primary action of vasoconstriction. Similarly, a decreased heart rate is not a typical effect of decongestants, as their adrenergic effects can actually lead to an increased heart rate in some cases.