One of the most common side effects of antidepressants is:

Xerostomia, or dry mouth, is a well-known side effect associated with many classes of antidepressants, particularly tricyclic antidepressants and certain selective serotonin reuptake inhibitors (SSRIs). This occurs because these medications can have anticholinergic effects, which reduce saliva production and lead to oral dryness.

Managing xerostomia is crucial, as it can significantly impact a patient's oral health, leading to increased risk of dental caries, periodontal disease, and discomfort. Patients experiencing this side effect often benefit from increased hydration, the use of saliva substitutes, or stimulation of salivary flow through other means.

The other options, while they do have their own clinical relevance or association with different medications, are less commonly recognized as prevalent side effects of antidepressants compared to xerostomia. For instance, gingival hyperplasia is more commonly linked to certain anticonvulsants rather than antidepressants. Delayed wound healing might be seen in patients on specific medications, but it is not a frequently cited side effect of antidepressants. Similarly, while bleeding can occur with certain medications, it is not among the most typical side effects of antidepressants. Thus, xerostomia stands out as the most common side effect in this context.