Which of the following is a potential side effect of tricyclic antidepressants (TCAs)?

Tricyclic antidepressants (TCAs), which are used primarily to treat depression, can lead to various side effects due to their mechanism of action that affects multiple neurotransmitter systems. Hypotension is a recognized side effect of TCAs because these medications can block alpha-adrenergic receptors, leading to vasodilation and a subsequent drop in blood pressure. Patients may experience dizziness, especially upon standing up (orthostatic hypotension), as a result of this drop in blood pressure.

In contrast, while some of the other potential options, such as increased appetite, can also be associated with TCAs, they are often not as significant as hypotension. Increased energy is generally not a side effect associated with TCAs; rather, they might initially cause sedation. Hypertension can occur in some cases, but it is not a common side effect of TCAs, especially relative to hypotension. Thus, hypotension emerges as the most relevant side effect among the choices provided.