Test Category: Specialist BiochemistryToxicology
Investigation Name:Amitriptyline / Nortriptyline
Alias or Abbreviation:AMIT
Accreditation:UKAS Accredited ISO15189:2022, on scope
Intro:
Amitriptyline and nortriptyline are tricyclic antidepressants frequently used to treat depression, neuropathic pain, and migraine prophylaxis. Whilst amitriptyline is metabolized to nortriptyline in the body, both are distinct medications.Amitriptyline has a low therapeutic index, and its therapeutic efficacy and safety can vary widely among patients. Overdose can lead to severe, potentially fatal outcomes. As well as identifying instances of overdose, clinical indications for monitoring include dose optimisation, assessment of compliance, management of drug interactions, reduction in risk of side effects and adverse events.
Pathology Laboratory:Toxicology Laboratory
Requestable Seperately?Yes
Units:µg/L
Minimum Sample Volume:1mL
Expected Turnaround Time:1 working day
Test Code:AMIT
Sample Type:
1mL of plasma or serum collected immediately prior to next dose, or minimum of 6 hours post dose (trough specimen).Complex Reference Range:For Nortriptyline alone:
Non-compliance, suboptimal dose <70 µg/L
Maximum drug efficacy 70-170 µg/L
Increased risk of side effects >300 µg/L
For Amitriptyline:
The TOTAL concentration (amitriptyline + nortriptyline) should be interpreted as follows:
Non-compliance, suboptimal dose: <80 µg/L
Maximum drug efficacy: 80-200 µg/L
Increased risk of side effects: >300 µg/L
Referred to Another Laboratory?No
Storage Requirements:Samples should be stored at 4°C prior to sending and should be sent at ambient temperature through the normal postal system.
Posting Address / Requirements:Sandwell Health Campus
Specialist Chemistry
Pathology Department
Lyndon
B71 4HJ
NPEX / PDF Reporting Available:NPEX and PDF reporting is available.
EQA Scheme:The laboratory is enrolled on EQA schemes for Amitriptyline/Nortriptyline with LGC Standards PT schemes. Samples are received monthly.
Lead Contact Details:Hayley Sharrod-Cole
Consultant Clinical Scientist
Email: hayley.sharrod-cole@nhs.net
Email Address For Chasing Results:rwh-tr.bcpsspecialistchemistryenquiries@nhs.net
Site Sample Tested:City Health Campus
Cost:Please email: bcpspathology.info@nhs.net for further details
Contact Number:0121 507 4138
