Which class of medications does NOT typically cause xerostomia?

The correct class of medications that does not typically cause xerostomia is the anti-tussives. Anti-tussives primarily function to suppress coughing by acting on the cough center in the brain or by numbing the throat. They generally do not have anticholinergic properties, which are responsible for dry mouth as a side effect.

In contrast, other classes of medications listed, such as antidepressants, antihistamines, and antihypertensives, can lead to dry mouth as a common side effect. Antidepressants, particularly those with anticholinergic effects, can decrease saliva production. Antihistamines, frequently used for allergies, are known for their drying effects due to their blockade of acetylcholine at muscarinic receptors. Antihypertensives, especially certain types, may also lead to xerostomia, though this can depend on the specific medication and its mechanism of action.