What common side effect could result from taking Clonidine?

Clonidine, which is primarily used to treat hypertension, acts on alpha-2 adrenergic receptors in the brain to reduce sympathetic outflow, leading to a decrease in heart rate and blood pressure. One of the well-known side effects of Clonidine is xerostomia, or dry mouth. This occurs because the medication can inhibit the action of the autonomic nervous system, which normally stimulates saliva production. Patients on Clonidine often report a dry sensation in the mouth, which can be uncomfortable and may impact their quality of life.

In contrast, other side effects presented in the options are less common or may occur due to different mechanisms or other medications. Cold sweat, tachycardia, and increased appetite are not standard or well-documented effects associated with Clonidine use. Understanding the pharmacological profile of Clonidine helps clarify why xerostomia is a more likely side effect for patients taking this medication.