Laboratory testing: Main menu - Simple and Practical Mental Health

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General

12 “sins” in laboratory testing in mental health

ICD-10 diagnostic codes for laboratory tests

Is it essential to be fasting for lab tests?

Biotin can interfere with many laboratory tests—and lead to serious misdiagnosis

Which laboratory tests should we order?

What laboratory tests should a mental health clinician order and when?

Clinicians’ guide to screening tests in mental health

What should I be doing to monitor patients who are on an antipsychotic?

Which laboratory tests should be done in persons taking valproate/ divalproex (Depakote-ER®)?

Which laboratory tests in persons with first-episode psychosis?

Which laboratory tests in men with erectile dysfunction?

A primer on tests for identifying 2019 novel coronavirus (SARS-CoV-2) infection

Alcohol use: Laboratory tests

How to use laboratory testing for alcohol use

Abstinence from alcohol can be monitored by a urine screening test

Real-life examples: How to identify recent alcohol use in urine and blood tests

Basic metabolic panel (BMP, Chem 7)

Also see: Kidney (Renal) Function Tests

How to calculate the corrected serum calcium

How to monitor for possible metabolic acidosis

What is the anion gap and how can we easily calculate it from the lab results?

Complete blood count (CBC)

Why we sometimes specifically order a “CBC with differential”

A primer on the Absolute Neutrophil Count (ANC)

How is beta-thalassemia minor relevant to mental health clinicians?

C-reactive protein

A primer on C-reactive protein

C-reactive protein and mental disorders

Electrocardiogram (ECG)

When to do an electrocardiogram (ECG or EKG)

How often should we order ECG (EKG) during treatment with a psychotropic medication?

Does this drug cause QT prolongation and torsades?

Antipsychotics and QT prolongation

Antibiotics, antipsychotics, and QT prolongation

Hydroxyzine (Vistaril®, Atarax®) and QTc prolongation

Can mirtazapine increase the risk of QT prolongation?

Lithium’s effects on the electrocardiogram (ECG, EKG)

Hormone levels

Should we look at serum FREE testosterone or TOTAL testosterone?

Exactly which test should we order to measure free testosterone?

Should we be checking testosterone levels in older men?

Should we check testosterone levels in men with “treatment-resistant” depression?

Iron studies

Laboratory testing to identify iron deficiency

How to order and interpret iron studies

What is the best single test for checking the body’s iron stores?

Restless Legs Syndrome (RLS) and iron deficiency

Are we missing iron deficiency without anemia?

Management of iron deficiency

Instructions for WHEN and HOW to take iron supplements

How to maximize absorption of iron supplements

How to improve the tolerability of iron supplementation

Iron deficiency, pica, and restless legs syndrome associated with blood donation

Let’s ask about heavy menstrual bleeding

Kidney (renal) function tests

What is the estimated GFR (eGFR)?

Useful tip about the next step when eGFR is low

What serum creatinine is and why it is important

Factors that can affect serum creatinine

Can creatine supplements lead to “false” elevation in serum creatinine?

Why it is important to longitudinally chart serum creatinine and eGFR values

Another way in which charting serum creatinine values can be helpful

How to know if the BUN and creatinine are elevated due to dehydration

In suspected kidney disease, check the urine albumin-creatinine ratio

24-hour urine for creatinine clearance

How to collect a 24-hour urine sample

Lipid panel

The lipid panel (profile): Why, when, and how to order it

Liver (hepatic) function tests

Tips about Hepatic Function Tests

False-positive elevation of plasma ammonia

Valproate (Depakote®) and elevated serum ammonia level (hyperammonemia)

Neuroimaging

Order an MRI of brain in first-episode psychosis?

Pharmacogenetic testing

Serotonin transporter promoter region

Serotonin transporter linked polymorphic region (5-HTTLPR)

5-HTTLPR and efficacy of antidepressants

5-HTTLPR and adverse effects of antidepressants

5-HTTLPR and antidepressant-induced mania

Serotonergic receptors

Serotonin 2A receptor gene (HTR2A) polymorphisms and adverse effects

HTR2C polymorphisms and medication-induced weight gain

Blood-brain barrier/ P-glycoprotein

ABCB1 polymorphisms and psychotropic medications

Cytochrome P450 enzymes

Pharmacogenetic testing: Cytochrome P450 enzymes

HLA gene testing

HLA antigens and psychotropic drugs

Melanocortin 4 receptor (MC4R)

Melanocortin 4 receptor (MC4R) and weight gain

Commercially-available pharmacogenomic tests

(listed alphabetically)

Genecept assay® (Genomind, LLC)

GeneSight® pharmacogenomic test batteries (Assurex Health)

Commercially available pharmacogenomic test panels

Miscellaneous

Clinical Pharmacogenetics Implementation Consortium (CPIC®)

Should you order genetic tests before prescribing psychotropics? (External Link)

Prolactin

How to measure and interpret serum prolactin

Serum levels of medications

General

When to measure serum levels of mood stabilizers

Clomipramine

When and how to check the clomipramine level

How to interpret clomipramine and desmethylclomipramine levels

Clozapine

How to check and interpret clozapine levels

Can oral contraceptives affect clozapine levels?

Lamotrigine

Lamotrigine level and adverse effects

Lithium

If serum lithium levels vary unexpectedly, consider these possible causes

Lithium augmentation in major depressive disorder: How much?

Nortiptyline

How to order and interpret the serum nortriptyline level

Oxcarbazepine

Oxcarbazepine (Trileptal®): Plasma levels

Valproate

What is the optimal serum valproic acid (valproate) level?

All about when and how to use FREE valproic acid levels

Thyroid function tests

Tips on thyroid function testing

How to identify clinical versus subclinical hypothyroidism or hyperthyroidism

What do you make of these thyroid function test results?

How should lithium-induced hypothyroidism be evaluated?

Urine drug screening

Which urine drug screen (UDS) should we specifically order?

Which urine drug screen do most workplaces require?

False-positive urine drug screen: Principles and a table for reference

Opioids in the urine drug screen

Special tests are needed to identify fentanyl in the urine

Standard urine drug screens can be false-negative for some benzodiazepines

Will zolpidem be detected on a standard urine drug screen?

For how long are substances detected in a urine drug screen (UDS)?

“Fingerprint” metabolites that uniquely identify substances in a urine drug screen

Vitamin levels

Folate

Serum folate is not the right test to order

Vitamin B12

How to evaluate a person’s vitamin B12 status

Testing for B vitamins in persons with cognitive impairment

A patient with a low vitamin B12 level

Which supplements to recommend with a vegetarian or vegan diet

Elevated vitamin B12 levels are common and could be very serious

Miscellaneous

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