Everyday Health Guide

Measures the number of platelets (tiny cell fragments in the blood that help it clot) in a microliter of blood. It is part of a standard Complete Blood Count (CBC). No fasting is required. A standard blood draw is performed.

Measures how well platelets (the blood cells responsible for clotting) clump together to stop bleeding. You may be asked to stop taking certain medications (like aspirin) for a week before the test. A standard blood draw is performed.

An overnight test that records brain waves, oxygen levels, heart rate, breathing, and eye/leg movements during sleep. Sensors are painlessly attached to the body. Avoid caffeine and alcohol on the day of the test.

Measures serum potassium (an essential electrolyte mineral that regulates nerve and muscle function, especially the heartbeat). Fasting is usually not required. A standard blood draw is performed.

Measures prealbumin (a protein made by the liver that changes quickly, making it a good marker for short-term changes in nutritional status or inflammation). No fasting is usually required. A standard blood draw is performed.

Measures progesterone (a female hormone that prepares the uterine lining for pregnancy and regulates the menstrual cycle). The timing of the blood draw depends on the menstrual cycle or pregnancy trimester. A standard blood draw is performed.

Measures prolactin (a hormone produced by the pituitary gland that stimulates milk production). It is best drawn in the morning, 3–4 hours after waking up, while fasting. Avoid breast stimulation or heavy exercise before the test. A standard blood draw is performed.

Measures PSA (a protein produced by the prostate gland, used as a marker for prostate health). Avoid ejaculation and vigorous exercise (like cycling) for 48 hours before the test, as they can temporarily raise levels. A standard blood draw is performed.

Uses TRUS (Transrectal Ultrasound, where a small probe is gently inserted into the rectum) to create detailed images of the prostate gland. An enema may be recommended beforehand to clear the bowel.

Measures Protein C (a natural anticoagulant, or blood-thinning protein, produced by the liver that helps prevent abnormal blood clots). Fasting may be required, and blood thinners can affect the result. A standard blood draw is performed.

Measures Protein S (another natural anticoagulant protein that works together with Protein C to prevent blood clots). Fasting may be required, and pregnancy or birth control pills can lower levels. A standard blood draw is performed.

Measures how long it takes for a blood sample to clot. It is often reported as an INR (International Normalized Ratio). No fasting is required. A standard blood draw is performed.

A group of tests that measure how well the lungs take in and release air and how efficiently they transfer oxygen into the blood. You will be asked to blow hard into a tube connected to a machine (spirometer). Avoid heavy meals and smoking before the test.

Measures the exact amount of beta-hCG (a hormone produced by the placenta during pregnancy) in the blood. This helps track the progress of the pregnancy or identify potential complications. No fasting is required. A standard blood draw (venipuncture, drawing blood from a vein) is performed.

Measures the exact levels of the three major types of immunoglobulins (antibodies that fight infections: IgG, IgA, and IgM) in the blood. No fasting is required. A standard blood draw is performed.

A RAST (Radioallergosorbent test, a blood test to detect specific allergies) measures the amount of IgE antibodies your body produces in response to specific allergens (like pollen, dust mites, or pet dander). No fasting is required. A standard blood draw is performed.

Measures the number of RBCs (cells that carry oxygen throughout the body) in a blood sample. It is part of a standard Complete Blood Count (CBC). No fasting is required. A standard blood draw (venipuncture, drawing blood from a vein) is performed.

Examines RBC morphology (the study of the size, shape, and structure of red blood cells) under a microscope to identify abnormalities. It is often part of a Complete Blood Count (CBC) with a manual smear review. No fasting is required. A standard blood draw is performed.