CriticalSSRI (selective serotonin reuptake inhibitor)×Calcineurin inhibitor (immunosuppressant)
Updated · Methodology
Mechanism
Tacrolimus can prolong QT and cause torsade, in the words of its SmPC, which also calls for caution in patients already on QT-prolonging drugs. The citalopram SmPC lists ongoing treatment with any drug capable of prolonging the QT interval among its contraindications, with no exceptions.
Symptoms
QTc prolongation on ECG, palpitations, dizziness, syncope. The end point is polymorphic ventricular tachycardia of the torsade type progressing to ventricular fibrillation. The risk is higher with hypokalaemia, hypomagnesaemia, bradycardia, decompensated heart failure and in women.
Management
The pair sits in the citalopram SmPC contraindications, so the question is which drug stays, not how far to cut the dose. Tacrolimus is not withdrawn after transplantation, so the antidepressant is chosen around it rather than the other way round. With QT-prolonging co-medication the tacrolimus label explicitly requires ECG monitoring and blood level control.
Check the full regimen, not just this pair
Opens the checker with these two drugs prefilled. Add the rest of the regimen and recompute additive risks.
Summary of a multi-drug list →
Medicine list: everything you take in one place →
Sources
- FDA: Prograf (tacrolimus) prescribing information (2013)– ; DailyMed setid 7f667de1-9dfa-4bd6-8ba0-15ee2d78873b
- AEMPS: Ficha técnica de Seropram 30 mg (citalopram) (2024)– AEMPS CIMA, nregistro 63564, revisión 01/2024, secciones 4.2, 4.3 y 4.4
- AEMPS: Ficha técnica de Prograf 5 mg (tacrólimus) (2026)– AEMPS CIMA, nregistro 61005, revisión 04/2026, secciones 4.4 y 4.5