Diet Pills and Home Pregnancy Test

Home pregnancy tests and diet pills have no relationship to each other, as they are made and used for two different purposes 2. Still, many women wonder if what they consume, including medications such as diet pills, can interfere with the accuracy of a pregnancy test. They might fear that diet medications in the bloodstream will lead to a false positive or negative on a home pregnancy test 2.

Diet Pills

Diet pills are drugs or herbs used to promote weight loss and aid you in dieting. Depending on the type of diet pill you take, such a drug might suppress your appetite or work to boost your metabolism and ensure that your body burns calories at a faster rate. Others reduce the body's absorption of fat by interfering with lipase, an enzyme that aids in the digestion of fat. Diet pills come in both over-the-counter, or OTC, and prescription form, and vary in terms of effectiveness. They also vary in terms of safety, and many can cause side effects such as increased blood pressure and temporary bowel incontinence.

Home Pregnancy Tests

Home pregnancy tests determine whether a woman is pregnant by reacting with a hormone called human chorionic gonadotropin, or HCG, in the urine 2. This hormone, commonly referred to as the pregnancy hormone, is usually only present in significant amounts when a woman is pregnant. Each pregnancy test has a different sensitivity level, however. This means some might only register positive when a woman has 50 mIU/ml or more of HCG in her urine, while others are designed to detect pregnancy before a woman ever misses a period and might detect levels as low as 20 mIU/ml.

Test Results and Diet Pills

Generally, the use of diet pills shouldn't affect the results of home pregnancy tests 2. These tests are only intended to test for the presence of HCG, and most diet pills do not contain the hormone. If diet pills have a diuretic effect, however, and increase the output of water from your body, your urine sample might not be as concentrated as normal and might produce a false-negative result. Likewise, if you take HCG in pill form, as some people do when following the HCG diet, the use of these diet pills might cause a false-positive on a home pregnancy test 2.


While most diet pills won't interfere with the results of a pregnancy test, taking them can sometimes affect conception. If you lose an excessive amount of weight or deprive yourself nutritionally, this could interfere with the hormonal changes necessary to allow you to become pregnant. In fact, if you lose a dramatic amount of weight and become severely underweight, you might develop irregular menstrual periods that interfere with your ability to conceive. However, safe weight loss accomplished by a healthy diet and exercise can boost fertility.