citalopram and escitalopram associated dose-dependent QT interval prolongation

Last edited 09/2020 and last reviewed 11/2022

Citalopram and escitalopram are associated with dose-dependent QT interval prolongation and should not be used in:

  • patients with congenital long QT syndrome or
  • known pre-existing QT interval prolongation combination with other medicines known to prolong the QT interval

ECG measurements should be considered for patients with cardiac disease, and electrolyte disturbances should be corrected before starting treatment.

New maximum daily doses New restrictions on the maximum daily dose of citalopram and escitalopram now apply (see Table below). Patients who currently take doses higher than the new recommended daily maximum should have their treatment reviewed.

New maximum doses for citalopram and escitalopram

Adults Adults > 65 years of age Adults with hepatic impairment
Citalopram 40mg* 20mg* 20mg*
Escitalopram 20mg 10mg* 10mg

*New (restricted) maximum daily dose.


  1. Citalopram and escitalopram: QT interval prolongation - new maximum daily dose restrictions (including in elderly patients), contraindications and warnings. Drug Safety Update December 2011
  2. MeReC Monthly No. 47 (February 2012)