'TCA-related' originates from modern English, combining the initialism 'TCA' (short for 'tricyclic antidepressant') and the adjective-forming element '-related' from the verb 'relate'. 'TCA' reflects 'tri-' meaning 'three' and 'cyclic' meaning 'ring-shaped'; 'antidepressant' denotes a drug that counteracts depression.

The abbreviation 'TCA' emerged in mid-20th century medical literature as 'tricyclic antidepressant' became a recognized drug class. The component 'related' derives from Latin 'relatus' via Old French/Middle English 'relaten/relate' and later produced the adjective form 'related' in modern English; the compound 'TCA-related' formed by compounding the initialism with 'related' is a recent, technical coinage.

Initially, 'tricyclic antidepressant' named a chemical class of drugs; over time the abbreviation 'TCA' was used adjectivally in medical contexts, and 'TCA-related' came to mean anything connected or attributable to TCAs (effects, interactions, research).