Synonym
Tubes
- 30-50 mL of midstream random urine
- Urine collected in a disposable sterile plastic collection container or plain tube as supplied by the laboratory
Additional information
- Use a freshly voided specimen
- Follow the chain of custody protocol, if required (for medicolegal purpose, this protocol may vary by institution)
- Ensure that the tested patient's signed informed consent form and photo identification are available
- Single (30mL) or 'split sample' (45mL) is collected under strict guidelines
- Sample temperature is checked immediately after collection
- Dilute samples (specific gravity <1.003, creatinine < 0.2 g/L) are re-collected
- Monitor specimen collection, labeling, and packaging to prevent tampering
- Send specimen to lab immediately
- Skin epithelium, bacteria, secretions, blood, hair, lint, etc should not contaminate the sample
- Instructions for clean catch midstream urine collection:
- For male
- Thoroughly wash his hands
- Cleanse the meatus
- Void a small amount into the toilet
- Void directly into the specimen container
- For female
- Thoroughly wash her hands
- Cleanse the labia from front to back
- While keeping the labia separated, void a small amount into the toilet
- Without interrupting the urine stream, void directly into the specimen container
- Prerequisites for therapeutic drug monitoring
- Dosage must be stable for at least ten days
- Dosage cannot be changed or missed
- Samples are collected within 10-15 hrs after the last dose
Info
- The Tricyclic Antidepressant Urine Drug Screen Assay detects the presence of various forms of tricyclic antidepressants (TCA) from urine
- TCAs are primarily used to treat depression and other conditions such as migraine, panic disorder, obsessive compulsive disorder, recurrent headaches, some forms of pain, and sleep disorders
- TCAs are used increasingly as an abuse drug in US [Substance Abuse and Mental Health Services Administration/SAMHSA, National Institute on Drug Abuse (NIDA)], thus mandatory drug testing is done in various situations
This section covers Urine testing for Tricyclic antidepressants. Other sections on urine toxicology testing include:
Clinical
- Testing for tricyclic antidepressants in urine is indicated in the following conditions:
- To investigate suspected drug overdosage
- Mandatory drug abuse testing in various situations such as:
- Pre-employment
- Prior to transfers or promotions
- Post-accident
- Reasonable suspicion
- Return-to-duty
- Periodic follow-up
- Random
- To monitor clinical response, side effects, or signs of toxicity and poisoning
- To evaluate altered behavior and determine if drug use is present
- To monitor suspected noncompliance with drug or alcohol treatment program
- Documentation of use or abstinence from barbiturates, for medicolegal purposes
- To monitor the drug levels and evaluate the therapeutic efficacy and compliance in special situations such as:
- Patients with hepatic dysfunction
- Very young and old persons
- Patients on multiple medications
- Some of the antidepressants include:
- Amitriptyline (Elavil)
- Amoxapine
- Clomipramine (Anafranil)
- Desipramine (Norpramin)
- Doxepin (Sinequan)
- Imipramine (Tofranil)
- Nortriptyline (Aventyl, Pamelor)
- Protriptaline (Vivactil)
- Toxicity / overdosage of TCA may clinically present as:
- Anticholinergic syndrome
- Blurred vision
- Dry mouth
- Fever (Hyperpyrexia)
- Hypoactive or absent bowel movements
- Mydriasis
- Myoclonic twitching
- Urinary retention
- Cardiovascular effects
- Cardiogenic shock
- Heart block
- Hypotension
- Peripheral vasodilatation
- Prolonged PR, QRS, and QT intervals
- Sinus tachycardia
- Ventricular arrhythmias
- CNS effects
- Coma
- Confusion
- Delirium
- Drowsiness
- Hallucinations
- Extrapyramidal signs
- Opthalmoplegia
- Respiratory depression
- Rigidity
- Seizures
Additional information
- The limitations with urinary screening of drugs include:
- It indicates exposure to the drug, but does not give the precise timing of use, or quantity used
- Level of impairment specifically attributable to a given illicit drug cannot be evaluated
- Cannot differentiate between taking one's routine dose and overdose or illicit use of TCAs
- Rapid card tests to screen drugs in urine has sensitivity cut-off value of 30 ng/mL for TCA
- TCA in urine should be detected preferably within 8-12 hrs, but high levels due to overdosage/poisoning can be detected up to 2-7 days
- Positive results for drug screening from urine (thin layer chromatography or rapid check card test) should be investigated for drug specific confirmatory tests (High-performance liquid chromatography, Gas Chromatography - Mass Spectrometry, others)
- Factors interfering with test results include
- Substitution of urine from a drug-free individual or of apple juice
- Adulteration of the specimen
- Ammonia
- Bleach (Sodium hypochlorite)
- Detergents
- Sodium chloride (Salt)
- Vinegar
- Water
- Interference from nonprescription drugs or foods
- Blood in the urine
- Technical error
- Administrative error (improper labeling of specimens, inaccurate recording of results)
- Interference from nonprescription drugs or foods
- Blood in the urine
- Technical error
- Administrative error (improper labeling of specimens, inaccurate recording of results)
- Related laboratory tests include:
This section covers Urine testing for Tricyclic antidepressants. Other sections on urine toxicology testing include:
Nl Result
- Consult your laboratory for their cutoff levels
- Different laboratories utilize different cutoff levels for a positive and negative results
- Duration of positive result from last use: 1-7 days
Interpretation | Value (ng/mL) |
---|
Negative result (Screening test) | <1000 |
Positive result (Screening test) | 1000 |
Confirmation of Screening test positive | 1000 |
This section covers Urine testing for Tricyclic antidepressants. Other sections on urine toxicology testing include:
High Result
A high result is consistent with use of TCA containing products, within the last 1-7 days.
This section covers Urine testing for Tricyclic antidepressants. Other sections on urine toxicology testing include:
Low Result
A low result is consistent with no recent use of TCA containing compounds.
Factors associated with false negative test results for benzodiazepines include:
- Adulterants present in the urine
- Dilution or replacement of the sample with tap water
- Ingestion of large amounts of fluid
- Substitution of another persons urine deliberately to avoid a positive test result
This section covers Urine testing for Tricyclic antidepressants. Other sections on urine toxicology testing include:
References
- ARUP Consult®. Drug Screen (Nonforensic), Comprehensive, Serum & Urine. [Homepage on the internet]©2007. Last accessed on May 5, 2007. Available at URL: http://www.aruplab.com/guides/ug/tests/0090560.jsp
- eMedicine from WebMD®. Toxicity, Tricyclic Antidepressant. [Homepage on the Internet] ©1996-2007. Last updated on November 3, 2006. Last accessed on May 5, 2007. Available at URL: http://www.emedicine.com/ped/topic2714.htm
- Giannini AJ. An Approach to Drug Abuse, Intoxication and Withdrawal. Am Fam Physician. 2000 May 1;61(9):2763-74. Available at URL: http://www.aafp.org/afp/20000501/2763.html
- Gillman PK. Tricyclic antidepressant pharmacology and therapeutic drug interactions updated. Br J Pharmacol. 2007 Apr 30; [Epub ahead of print].
- LabTestsOnline®. Testing for Drugs of Abuse. [Homepage on the Internet] ©2001-2007. Last reviewed on March 20, 2006. Last accessed on May 5, 2007. Available at URL: http://www.labtestsonline.org/understanding/analytes/drug_abuse/glance.html
- National Institute on Drug Abuse®. Commonly Abused Drugs. [Homepage on the Internet] ©1996-2007. Last updated on March 31, 2007. Last accessed on May 5, 2007. Available at URL: http://www.drugabuse.gov/DrugPages/DrugsofAbuse.html
- Regional Laboratory for Toxicology®. Drugs of Abuse Guidelines. [Homepage on the Internet] ©2002. Last modified on April 13, 2005. Last accessed on May 5, 2007. Available at URL: http://www.toxlab.co.uk/dasguide.htm
- Woolf AD et al. Tricyclic antidepressant poisoning: an evidence-based consensus guideline for out-of-hospital management. Clin Toxicol (Phila). 2007;45(3):203-33.