Evidence-Based Supplement & Herb Guides

PTT-LA Test: Lupus Anticoagulant Screening, Prolonged Clotting Time, and Meaning

Understand what the PTT-LA test screens for, why a prolonged result is not diagnostic, how mixing and confirmation work, and what the result may mean for lupus anticoagulant and APS.

The PTT-LA test is an activated partial thromboplastin time designed to be sensitive to lupus anticoagulant. It measures how long plasma takes to clot...

Recurrent Pregnancy Loss Antiphospholipid Panel: APS Markers, Miscarriage Risk, and Meaning

Learn which APS markers are included in recurrent pregnancy loss testing, how positive and negative patterns are interpreted, why 12-week confirmation matters, and how results may guide a future pregnancy.

A recurrent pregnancy loss antiphospholipid panel checks for antibodies associated with obstetric antiphospholipid syndrome (APS), an acquired autoimmune condition that can contribute to miscarriage,...

Seronegative Antiphospholipid Syndrome Test Panel: Non-Criteria Antibodies and APS-Like Symptoms

Learn what a seronegative APS test panel may include, why non-criteria antibodies require cautious interpretation, and how specialists evaluate APS-like symptoms when standard markers are negative.

Seronegative antiphospholipid syndrome is a proposed diagnosis for people with thrombosis, pregnancy morbidity, or other strongly APS-like features who repeatedly test negative for the...

Thrombosis Antiphospholipid Panel: Clotting Risk, APS Markers, and Meaning

Learn what a thrombosis antiphospholipid panel measures, when APS testing is useful after a clot, how anticoagulants affect results, and what single, double, or triple positivity may mean.

A thrombosis antiphospholipid panel looks for the persistent autoimmune markers that support antiphospholipid syndrome (APS) in a person with a confirmed blood clot. The...

Triple-Positive Antiphospholipid Antibody Panel: High-Risk APS, Clotting Risk, and Meaning

A triple-positive antiphospholipid antibody panel means that all three standard APS laboratory categories are positive: lupus anticoagulant, anticardiolipin antibodies, and anti-beta-2 glycoprotein I antibodies....

Acute Tryptase Test: Anaphylaxis, Mast Cell Activation, Timing, and Interpretation

Learn when to draw an acute tryptase test, how to compare it with baseline using the 20% plus 2 rule, and why a normal result does not exclude anaphylaxis.

An acute tryptase test is a time-sensitive blood test used to look for evidence that mast cells released their contents during a suspected anaphylactic...

Allergy Blood Test Panel: Total IgE, Specific IgE, Allergen Triggers, and Meaning

Understand what an allergy blood test panel measures, how total and specific IgE differ, why positive results may not equal allergy, and when focused follow-up is needed.

An allergy blood test panel measures immunoglobulin E antibodies in a blood sample. Depending on the order, it may include total IgE, specific IgE...

Alpha-Gal IgE Test: Red Meat Allergy, Tick Bite, Delayed Reaction, and Meaning

Learn how the alpha-gal IgE test helps diagnose delayed red-meat allergy after tick bites, what positive and negative results mean, and how to manage exposure safely.

The alpha-gal IgE test is a blood test used to help diagnose alpha-gal syndrome, an allergy linked to tick bites and reactions to a...

Baseline Tryptase Test: Mastocytosis, Mast Cell Burden, Hereditary Alpha-Tryptasemia, and Meaning

Learn how a baseline tryptase test is collected and interpreted, including reference ranges, hereditary alpha-tryptasemia, mastocytosis criteria, and appropriate follow-up.

A baseline tryptase test measures the stable amount of tryptase circulating when a person is well and at least 24 hours beyond a suspected...

Basophil Activation Test: Allergy Testing, CD63, CD203c, and Reaction Risk

Learn how the basophil activation test uses CD63 and CD203c to assess functional allergy, how results are interpreted, and why BAT cannot precisely predict future reaction severity.

The basophil activation test, or BAT, is a specialized blood test that exposes a patient’s living basophils to a suspected allergen in the laboratory....

Chronic Urticaria Blood Test Panel: IgE, Tryptase, Thyroid Antibodies, and Autoimmune Causes

Learn which blood tests are useful for chronic urticaria, how total IgE, tryptase, anti-TPO antibodies, and autoimmune markers are interpreted, and when broader testing is needed.

A chronic urticaria blood test panel is not one fixed set of tests and usually should be limited. Chronic urticaria means recurrent hives, angioedema,...

Drug Allergy IgE Test: Medication Allergy Markers, Positive Result, and Limitations

Learn what a drug allergy IgE test can detect, which medications have supported assays, why negative results are limited, and how skin tests or supervised challenges clarify a drug allergy label.

A drug allergy IgE test is a blood test that looks for immunoglobulin E antibodies to a specific medication or a drug-related chemical structure....

Egg Component IgE Test: Ovomucoid, Ovalbumin, Allergy Risk, and Meaning

Understand ovomucoid and ovalbumin IgE results, how heat changes egg proteins, what positive values mean, and why a supervised food challenge may still be needed.

An egg component IgE test measures antibodies to individual egg proteins rather than reporting only a whole egg white result. The two components most...

Environmental Allergy IgE Panel: Pollen, Mold, Dust, Pets, and Allergy Triggers

Learn how an environmental allergy IgE panel tests pollen, mold, dust mites, pets, and pests, what positive results mean, and how findings guide exposure control.

An environmental allergy IgE panel is a blood test that looks for immunoglobulin E antibodies to airborne allergens such as tree, grass, and weed...

Eosinophil Cationic Protein Test: Asthma, Allergy Inflammation, and Eosinophil Activity

Learn what an eosinophil cationic protein test measures, why ECP rises, how sample handling affects results, and how it compares with eosinophils and FeNO.

An eosinophil cationic protein test measures ECP, a granule protein released mainly by activated eosinophils. Eosinophils are white blood cells involved in type 2...

Eosinophil Count Test: Allergy, Asthma, Parasites, High Eosinophils, and Meaning

Learn how an eosinophil count is reported, what mild and marked elevations mean, and how allergy, asthma, parasites, drugs, and systemic disease are evaluated.

An eosinophil count measures a type of white blood cell involved in allergic inflammation, defense against some parasites, and several immune and blood disorders....

Food Allergy IgE Panel: Common Foods, Positive Results, Allergy Risk, and Meaning

Learn what a food allergy IgE panel measures, why positive results may not equal allergy, how cross-reactivity affects testing, and when a supervised challenge is needed.

A food allergy IgE panel is a blood test that measures immunoglobulin E antibodies to several foods at once. Panels commonly include milk, egg,...

Histamine Blood Test: High Levels, Allergy, Mast Cell Activation, and Meaning

Learn what a histamine blood test measures, why timing and specimen handling matter, what high levels may mean, and why tryptase or urine markers are often preferred.

A histamine blood test measures histamine in plasma, whole blood, or another specified blood fraction. Histamine is a short-lived signaling molecule released by mast...

Histamine Release Test: Allergy Reaction, Basophils, and IgE-Mediated Response

Learn how a histamine release test measures basophil function, how direct and urticaria assays differ, what positive results mean, and why nonresponders limit testing.

A histamine release test is a functional laboratory assay that measures how much histamine basophils release after they are exposed to an allergen, anti-IgE...

Insect Venom IgE Test: Bee, Wasp, Hornet Allergy, and Anaphylaxis Risk

Learn how insect venom IgE testing helps diagnose bee, wasp, and hornet allergy, interpret positive or negative results, assess anaphylaxis risk, and guide venom immunotherapy.

An insect venom IgE test measures antibodies directed against venom from honeybees, yellow jackets, paper wasps, hornets, or other stinging insects. It is most...