You suspect: High Cholesterol

The test: Home Access Instant Cholesterol Test, $15, drugstores
Experts say: Don’t try this at home.
""Cholesterol levels don’t change that quickly, so there’s no need to have them checked more than a few times a year,"" explains Marc Eisenberg, M.D., of Columbia University Medical Center. Plus, the kit only measures your total cholesterol count, rather than separating HDL and LDL levels (""good"" and ""bad"" cholesterol, respectively), so it’s not providing enough information for an accurate assessment, he says. To determine whether your LDL levels are problematic, doctors factor in both readings, as well as your triglyceride (blood fat) levels, and develop what’s known as a ""full lipid profile.""

You suspect: Allergies

The test: MyAllergyTest, $50,immunetech.com
Experts say: Save your money.
This test, which requires that you prick your finger and send your blood sample in a small vial to the company’s lab, doesn’t screen for enough allergens to be worthwhile, explains Russell Leftwich, M.D., an allergist in Nashville, Tenn. The 10 substances the kit tests for are some of the most common offenders (pollen, ragweed, pet dander), “but they’re not the only ones — allergy causes vary depending on where you live,” he notes. During an ""official"" allergy screening, doctors test for about 70 substances.

You suspect: High Blood Pressure

The test: Omron Manual Blood Pressure Monitor, $50, drugstores
Experts say: Pick it up.
The cuff offers an ideal way for people taking blood pressure medication to make sure it’s working as it should. In fact, many high blood pressure patients who are having a hard time determining the right medication and dosage are encouraged by their physicians to purchase a cuff, and make note of their readings several times daily. ""Ask your doctor to calibrate the machine and show you how to use it; people often wrap it around the wrong spot on their arm, which can throw off their readings,"" says Dr. Eisenberg.

You suspect: A Urinary Tract Infection

The test: UTI Home Screening Test, $12, drugstores
Experts say: Leave it on the shelf.
Doctors’ tests zero in on solid infection indicators like bacteria, an abnormal white blood cell count and blood in the urine, but at-home testing kits only screen for one possible indicator: high protein levels. Translation? You could easily get a negative reading and still have a UTI, says Sandra Culbertson, M.D., spokesperson for the American Urogynecologic Society.

You suspect: A Yeast Infection

The test: Vagisil Screening Kit, $17, drugstores
Experts say: Add it to your cart.
This test, which measures pH levels in the vagina, will quickly tell you whether you're suffering from a yeast infection, which can be treated with over-the-counter products, or a bacterial infection, which requires antibiotics, says Donnica Moore, M.D., a women’s health expert in Far Hills, N.J.
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