Which classes of anti-hypertensive agents are known to cause dry mouth?

The correct answer identifies the classes of anti-hypertensive agents that are known to cause dry mouth, specifically focusing on α1 antagonists and Central α2-agonists.

α1 antagonists, such as prazosin and doxazosin, can lead to a reduction in sympathetic nervous system activity which can influence salivary gland function, potentially resulting in reduced saliva production and consequently causing dry mouth.

Central α2-agonists, such as clonidine, exert their effects by stimulating receptors in the brain that inhibit sympathetic outflow. This action can also diminish salivation, further contributing to the experience of dry mouth.

While other classes mentioned may have their side effects, α1 antagonists and Central α2-agonists are particularly noted for causing this specific symptom due to their modes of action that alter autonomic nervous system functions related to saliva production.