How to Say "medical complication" in Spanish
The Spanish word for “medical complication” is “complicación” — B2 level.
English → SpanishB2
nounB2formal
a secondary disease or condition aggravating an existing one

Examples
El paciente tuvo complicaciones después de la cirugía.
The patient had complications after the surgery.
Es una medicina segura con pocas complicaciones.
It is a safe medicine with few complications.
Existen riesgos de complicaciones respiratorias.
There are risks of respiratory complications.
Using with 'tener'
When talking about health, we usually say someone 'has' complications using the verb 'tener'.
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