NCLEX Review Guide: Tricyclic Antidepressants (TCAs)

Tricyclic Antidepressants Fundamentals

• TCAs are first-generation antidepressants that work by blocking reuptake of norepinephrine and serotonin at nerve terminals, increasing availability of these neurotransmitters in synaptic clefts.
• Common TCAs include amitriptyline, nortriptyline, imipramine, and desipramine - remember these end in "-ine" or "-line".
• Therapeutic effects typically take 2-4 weeks to manifest, but side effects occur immediately upon initiation.

Therapeutic Uses

• Primary indication is major depressive disorder, particularly when other antidepressants have failed or when sedation is desired.
• Secondary uses include chronic pain management, migraine prevention, and certain anxiety disorders.
• Nortriptyline is often preferred in elderly patients due to fewer anticholinergic effects compared to amitriptyline.

Anticholinergic Effects

• Dry mouth, constipation, urinary retention, and blurred vision are the most common anticholinergic effects requiring patient education.
• Orthostatic hypotension occurs due to alpha-1 adrenergic blockade and requires gradual position changes and fall precautions.
• Sedation is prominent, especially with amitriptyline, making bedtime dosing preferable to minimize daytime drowsiness.

Critical Nursing Actions

1. Obtain baseline ECG and monitor for cardiac conduction abnormalities, especially QT prolongation
2. Assess suicide risk regularly, as depression may worsen initially before improvement occurs
3. Monitor for anticholinergic effects and implement preventive measures (increased fluids, fiber, safety precautions)
4. Educate about gradual position changes to prevent falls from orthostatic hypotension
5. Emphasize medication compliance and warn against abrupt discontinuation

Frequently Missed Concepts

• Students often confuse therapeutic lag time with side effect onset - remember side effects occur immediately while benefits take weeks.
• Don't forget that TCAs can lower seizure threshold in susceptible patients.
• Weight gain is a common long-term effect that affects medication compliance and requires dietary counseling.