**Core Concept:** Antidepressants can have various side effects, including anticholinergic effects. Anticholinergic side effects refer to the interference with the action of acetylcholine, a neurotransmitter involved in various physiological processes, particularly in the gastrointestinal, urinary, and cardiovascular systems. In the context of antidepressants, anticholinergic effects are detrimental as they can cause dry mouth, blurred vision, constipation, and increased heart rate.

**Why the Correct Answer is Right:** Fluoxetine (Prozac) is a selective serotonin reuptake inhibitor (SSRI) antidepressant that effectively enhances the availability of serotonin in the synaptic cleft without significantly affecting acetylcholine. This selective action minimizes the anticholinergic side effects commonly seen with other antidepressants.

**Why Each Wrong Option is Incorrect:**

A. Amitriptyline (Elavil) is an older tricyclic antidepressant (TCA) that can have significant anticholinergic effects due to its broader pharmacological profile.
B. Paroxetine (Paxil) is another SSRI with some degree of anticholinergic side effects.
C. Escitalopram (Lexapro) is another SSRI with some degree of anticholinergic side effects.
D. Mirtazapine (Remeron) is an atypical antidepressant with anticholinergic side effects due to its broader pharmacological profile.

**Clinical Pearl:** Fluoxetine is a widely prescribed antidepressant because of its minimal anticholinergic effects compared to other antidepressant classes. This makes it a preferred choice for patients who are more prone to anticholinergic side effects.