Preferred Sample Type


Suitable Specimen Types

  • Serum
  • EDTA Plasma
  • Li Hep Plasma
A minimum of 500 ┬Ál of plasma/serum is required.

Specimen Transport

First class post

Sample Processing in Laboratory

Place sample in toxicology rack.

Sample Preparation

None required

Turnaround Time

3 days.

Sample Stability

Keep refrigerated. 4 degrees.


General Information

Citalopram is a member of the group of selective serotonin reuptake inhibitors (SSRIs) that includes fluoxetine, paroxetine and sertraline and has been used clinically as an antidepressant since 1984. Adult doses of 20 - 60 mg are to be taken once daily. The S-enantiomer, escitalopram, is also available as a pharmaceutical agent.

Citalopram is known to undergo biotransformation via mono- and di-N-demethylation, oxidative deamination, N-oxide formation and glucoronide conjugation. The mono-N-desmethyl metabolite (desmethylcitalopram) has 25-50% of the pharmacological activity of the parent drug.

Adverse effects associated with citalopram therapy include drowsiness, somnolence, hyponatremia, dizziness and tachycardia. Hepatotoxicity has also been reported. The coadministration of monoamine oxidase inhibitors (MAOIs, e.g. hydrazines) is contraindicated due to the possibility of developing serotonin syndrome. Serotonin syndrome has also occured in patients receiving fentanyl, linezolid, meperidine or tramadol. Acute overdosage of 600 mg or more of citalopram may cause EKG abnormalities, whereas doses in excess of 1900 mg may often result in seizures.

Patient Preparation

No patient preperation required.


Citalopram measured by LC-MS/MS


Reference Range

Citalopram Therapeutic range - 50 - 110ug/L

Desmethylcitalopram may weakly contribute to pharmacological actions.

Please contact the laboratory if citalopram measurement is required for therapeutic monitoring purposes.

Citalopram is measured by LC-MS/MS.


  • EQA Scheme?: Yes

The laboratories at Heartlands Hospital, Good Hope Hospital and Solihull Hospital form part of the services provided by University Hospitals Birmingham and are UKAS (United Kingdom Accreditation Service) accredited to the ISO 15189:2012 standard. For a list of accredited tests and other information please visit the UKAS website using the following link:

  • Heartlands, Good Hope and Solihull Hospital pathology laboratories are a UKAS accredited medical laboratory No.8217
  • United Kingdom Health Security Agency laboratory is a UKAS accredited medical laboratory No.8213

Tests not appearing on the UKAS Schedule of Accreditation currently remain outside of our scope of accreditation. However, these tests have been validated to the same high standard as accredited tests and are performed by the same trained and competent staff.

For further test information, please visit the test database:

Protection of personal information - Laboratory Medicine comply with the Trust Data Protection policy and have procedures in place to allow the Directorate and its employees to comply with the Data Protection act  1998 and associated best practice and guidance.

For further information contact Louise Fallon, Quality Manager, 0121 424 1235