Can biotin cause false positive pregnancy test

• Consumption of mega doses of Biotin (100 - 300 mg/day) can cause positive or negative analytic interference with laboratory tests, including beta-hCG, cardiac Troponin and thyroid tests such as TSH and Free T4. Biotin may also alter the results of urine pregnancy tests Biotin in patient samples can cause falsely high or falsely low results, depending on the test. Incorrect test results may lead to inappropriate patient management or misdiagnosis Biotin supplements can cause false low levels in blood tests. That means you may be pregnant or experiencing an ectopic pregnancy or miscarriage and might not know it. In urine tests, high levels of biotin may prevent the control line on your home pregnancy test from appearing, yielding invalid results We study 23,692 people who take Biotin or have Pregnancy test urine positive. No report of Pregnancy test urine positive is found in people who take Biotin. The phase IV clinical study analyzes which people take Biotin and have Pregnancy test urine positive. It is created by eHealthMe based on reports from the FDA, and is updated regularly But biotin may interfere with some laboratory testing, causing results of tests to be either falsely high or falsely low. These inaccurate test results can cause healthcare practitioners to misdiagnose and mistreat their patients. Laboratory professionals have known about this potential problem for some time

Pregnancy tests and biotin! | BabyCenter

It may cause a false-positive reading on an at-home pregnancy test, particularly if the test is taken too early. Other medications can also cause false-positive pregnancy tests. They include but.. 8. You have a medical condition. This is a rare one, but some medical conditions such as certain kinds of cancer , chronic kidney disease, as well as problems with your ovaries could cause the body to have increased levels of HCG and potentially lead to a false-positive pregnancy test Ectopic pregnancy. A rare cause of a false positive pregnancy test, an ectopic pregnancy occurs when a fertilised egg implants itself outside the uterus - commonly in the Fallopian tubes. Sadly, an ectopic pregnancy can't continue because there isn't anywhere for the embryo to grow

Biotin Supplements and hCG - Trying for a baby

The FDA Warns that Biotin May Interfere with Lab Tests

In some cases, extra biotin causes falsely high results on tests. In others, it causes the results to read as falsely low. That's true with some ways to detect a protein called troponin, which.. False test results are an ongoing concern during the coronavirus disease 2019 (COVID-19) pandemic. Now some experts are warning that biotin supplements might interfere with COVID-19 antibody testing. Many lab assays use biotin, so it's well-known that taking biotin can skew numerous other lab results Depending on your dosage, high levels of biotin may cause false-positives or false-negatives for different lab tests, says Petrover, like thyroid hormone tests.And if your lab results are. Biotin Interference with Immunoassays . Biotin-streptavidin technology is widely utilized by manufacturers of immunoassays such as those used for routine clinical measurement of thyroid stimulating hormone and prolactin. Extremely high concentrations of circulating biotin can significantly interfere with immunoassays, leading to eithe

You asked: Can biotin give you a false negative pregnancy

Many tests employ technology that uses biotin to generate test results. If you take a biotin supplement, it can produce false-positive or false-negative lab test results, which may lead to misdiagnoses or unnecessary treatments for heart disease, thyroid conditions, breast cancer, pregnancy and fertility During the period 2000-2017, the accumulated risk of a 'false positive' result was 16.2% adjusted for age, sex and type of test. These data indicate that participants who begin screening at the. Vitamin C is a water-soluble nutrient not produced by your body. You must consume it fairly regularly, at least in small doses, to avoid any symptoms of deficiency. Eating foods rich in vitamin C or supplementing with it is not known to affect the results of a home pregnancy test, which tests for a specific hormone Biotin is the main vitamin in supplements that promise to improve your hair and nails. The FDA just released a warning about these supplements because they can skew the results of blood tests. Very high levels of biotin could cause a false positive on a pregnancy test or a false negative in a cancer screening TUMOR MARKERS. In addition, it can interfere - disastrously - as well documented by Amitava Dasgupta at the University of Texas, and cause inaccurate readings of tumor marker tests (which are biotin-based and rely on biotin to bind to the tumor antigen) for: • CA 15-3 (false negative, with 40% reduction reported

Biotin and Pregnancy test urine positive, a phase IV

A very rare cause of a false negative pregnancy test is when the hCG hormone in your body does not react with the anti-hCG chemicals in the test. In this case, you might need to wait a few more days before you can get a positive result or need to have a blood test Objectives: We determined the percentage of true vs false-positive HCV antibody (anti-HCV) test results among 2007-2012 participants in the National Health and Nutrition Examination Study (NHANES), a nationally representative study with approximately 1% HCV infection prevalence, much lower than in groups typically recommended for HCV screening Many tests employ technology that uses biotin to generate test results. If you take a biotin supplement, it can produce false-positive or false-negative lab test results, which may lead to misdiagnoses or unnecessary treatments for heart disease, thyroid conditions, breast cancer, pregnancy and fertility

FDA Warns that Biotin May Affect Some Lab Test Results

As noted in the original safety communication, while biotin in patient samples can cause falsely high or falsely low results, depending on the type of test, the FDA is particularly concerned about. High levels of biotin can impact tests used to diagnose conditions such as: Thyroid disease. Heart disease. Pregnancy. Anemia. Cancer. Other hormonal-related diseases. Results may appear falsely.

Biotin is often taken as a supplement for a variety of proposed health benefits. There are numerous reports of biotin interference with laboratory testing, specifically with thyroid function tests. This study reports the use of multivitamins and biotin supplements by outpatients in Rochester, Minnesota, and also reports plasma biotin levels in patients seen in the Mayo Clinic emergency department The FDA is warning that high doses of the vitamin B7, or biotin, in dietary supplements can interfere with hundreds of common lab tests—including some relied on by ER doctors to diagnose a heart. Electronic health records could be updated to display an alert to clinicians at the time of test order whenever tests with known biotin interference are ordered. Clinicians should contact the laboratory when laboratory results do not fit the patient's clinical picture or if the patient is known to have consumed a dose of biotin >5 mg (48, 49) Biotin supplements can confound laboratory results and mimic diagnosis patterns of Grave's disease, reports the new phenomenon brought recently to light by researchers from the Heinrich Heine University Hospital Duesseldorf, Germany.. The review, published recently in NEJM, says that a high-dose intake of biotin supplements can throw off test results, leading to a misdiagnosis of Grave's. 12) Antidepressants. Several antidepressants can cause false positives. Venlafaxine (Effexor XR) is a commonly prescribed serotonin-norepinephrine reuptake inhibitor (SNRI) antidepressant used for anxiety, depression, and menopausal hot flashes. Taking venlafaxine can result in a false positive urine test for PCP.; Quetiapine (Seroquel) is an atypical antidepressant drug used to treat bipolar.

False-Positive Pregnancy Test: 7 Possible Cause

But new research shows that biotin could have a shady side. A study in Clinical Laboratory News found that taking high doses of the vitamin might skew diagnostic test results, leading to false. Biotin and False Thyroid Test Results Biotin (vitamin B7) is a water-soluble vitamin well known for its benefits for healthy skin, nails, hair growth, energy production, and metabolism. It wasn't until recently, however, when researchers reported concerns with lab test interference issues prompting the FDA to release warnings and safety alerts on its use For 45% of people with a positive Cologuard test, no abnormalities will be found upon colonoscopy. You are right that false positives are more prevalent in older individuals Dangerous Lab Interference causing false-positive/negative. Biotin in blood or other samples taken from patients who are ingesting high levels of biotin in dietary supplements can cause clinically significant incorrect lab test results. High dose biotin may interfere with diagnostic assays that: Use biotin-streptavidin technolog

High biotin intakes, and potentially even intakes greater than the AI, may pose another type of health risk . Supplementing with biotin beyond recommended intakes can cause clinically significant falsely high or falsely low laboratory test results, depending on the test The type of COVID-19 test that UC Health uses — a PCR test, which looks for genetic material of the novel coronavirus — is the gold standard test. False positives and false negatives, therefore, aren't common, said Dani Zander, MD, chief of Pathology and Laboratory Medicine at UC Health. A false-negative test can happen if one has a. It can also prevent blood levels of biotin from becoming too low. Low blood levels of biotin can cause thinning of the hair and rash around the eyes, nose, and mouth. Other symptoms include. Pregnancy. Hormone supplements taken by women can affect the results of a blood test used to measure the amount of human chorionic gonadotropin, or HCG, in the blood. The body produces the HCG hormone during pregnancy. Hormone supplements can cause the test results to show a false positive by indicating a pregnancy when there isn't one

8 Possible Causes for a False-Positive Pregnancy Test

  1. Delayed reading can also result in a false-positive result, particularly with a latex agglutination test. Physiological blood loss in the occasional subject outside the normal range can also cause a false-positive result. Haemorrhoids and other non neoplastic conditions can occasionally cause a false-positive result, as may straining at stool
  2. Biotin may block test assay signals, leading to falsely elevated test results. Biotin may compete with biotin-containing complexes the test utilizes, which can lead to falsely low results. Exactly which lab tests are potentially affected by biotin, and by what extent, isn't well known and evidence suggests that there may even be variability.
  3. 5 thoughts on Four reasons for a positive hCG test in the absence of pregnancy David Grenache, PhD October 20, 2011 at 7:12 am. Hanna, That's an excellent question! I should have included exogenous hCG in my post as well because when injected at high doses (for ovulation induction or, illicitly, in conjunction with anabolic steroids) hCG can cause positive results
  4. Test Interactions Biotin can significantly interfere with certain lab tests and cause incorrect test results, including false negative results (eg, falsely low troponin) or false positive results (eg, thyroid function tests appearing as Graves disease), possibly leading to inappropriate patient management or misdiagnosis (Bowen 2019; FDA Safety.
  5. Table 1 summarizes the false-positive rates at various population prevalence for the Cellex test and for a hypothetical test that is 90% sensitive and 99% specific.1 At relatively low population.
  6. False positive results may occur with specimens drawn from pre-term infants, or with improper handling of the specimen. Improper drying, delayed submission or exposure to excess heat are all factors that can destroy the enzyme. Transfusions may cause false negative results
  7. 4 Causes Of A False Positive Pregnancy Test. There are no medications to my knowledge that can cause a false negative pregnancy test. If used properly, the pregnancy tests that can be purchased over the counter at the grocery store or at the pharmacy have a very high sensitivity. This means that they are able to pick up pregnancy when its.

She was taking supraphysiologic doses of biotin which could have influenced the results. Li et al. have demonstrated that biotin could interfere with the assay and result in suppressed TSH and elevated free T4, producing a false diagnosis of thyrotoxicosis . This explanation, however, fails to consider the positive RAIU scan in this patient Extra fluids can dilute your hGC levels and cause your test to fail. Each test has different positive and negative indicators, so read your package carefully to make sure you know what the various results mean. Some common results for pregnant are: A smiley face. A pink line. A blue line. The word pregnant Biotin is a form of vitamin B found in foods. Biotin helps the body break down fats, carbohydrates, and proteins. Biotin has been used in alternative medicine as a likely effective aid in treating or preventing biotin deficiency. Biotin deficiency can be caused by malnutrition, rapid weight loss, long-term tube feeding, and other medical. can taking high doses of kelp cause a false high tsh reading? i don't have any other symptoms of hypothyroidism, but my lab results were 7.13 Dr. Rebecca Gliksman answered 38 years experience Internal Medicin Vitamin B7 can not obstruct your body's response to fight back the viral infection. If you were really infected, antibodies would have certainly formed and it would have been detected by test, except chemo/cancer nothing will cause delayed seroconversion for a false negative. 2

Why pregnancy tests can show the wrong result Tell Me Bab

  1. If 1,000 uninfected people are tested with an HIV test and 4 have false-positive results, the HIV test's specificity is 99.6% (996 true negative test results/1,000 HIV uninfected persons tested). Causes of False-Positive HIV Test Results False-positive test results can occur due to technical issues associated with the test or biological.
  2. Yes, if the test is performed before implantation occurs (ie, test performed too early). See Question 2. Question 5. Are there other causes of a false-negative serum hCG test result? Yes. Very high concentrations of hCG, as seen in gestational trophoblastic disease, can cause a false-negative result or a lower-than-expected result
  3. The authors concluded that false-positive PCP test results were due to the cross-reactivities of ibuprofen, metamizole, dextromethorphan, and their metabolites with the PCP assay. 74 Thioridazine is known to cause false-positive PCP test results with both EMIT d.a.u and EMIT II PCP immunoassays. 75 Venlafaxine and its metabolites also may cause.

At this point, nor there is concrete data available to decisively make a statement that biotin can cause false positive neither it is logical to make that assumption by any means as explained above. Thus, this concludes the thread right here A negative hCG test does not rule out very early pregnancy due to its low negative predictive value during this stage. Elevated leukocyte concentrations may cause false positive results in hCG assays. HCG testing may not be valid in patients taking high dose biotin supplements and having certain qualitative tests Biotin, also known as Vitamin B7, is often present in prenatal vitamins to prevent deficiencies in vitamin B7 which can sometimes occur during pregnancy. It is known that Biotin can affect some laboratory tests, including thyroid tests such as Thyroid Stimulating Hormone (TSH) and free thyroxine levels, resulting in falsely high or low levels. They can give a false-positive test for marijuana. Ranitidine (Zantac), an acid-reducing drug also used for these conditions, can yield a false-positive result for amphetamines. A false-positive LSD test can occur in people taking metoclopramide (Reglan), a drug used for esophagus disorders or as an anti-nauseant

However, much like any diagnostic tool, there are odds that your test can deliver false negative and positive results. readmore 02 /7 COVID-19 tests may not be extremely accurat However, I am quite certain that b2 does not cause a false positive on drug tests. It can make your urine bright yellow & some who drink a lot of fluids to dilute their urine before a test will sometimes take b2 so the urine looks yellow rather than clear. Will not cause false positive. 5.5k views Reviewed >2 years ago A false positive result is an error, which means the result is not giving you the correct information. As an example of a false positive, suppose a blood test is designed to detect colon cancer. The test results come back saying a person has colon cancer when he actually does not have this disease. This is a false positive The risk of ruining important test results comes into play with supplements, which can have up to 650 times the recommended daily intake of the vitamin, says the FDA. It's this level of biotin that could cause a false positive on a pregnancy test or a false negative in a cancer screening

6 Things That Can Cause a False-Positive Pregnancy Test SEL

False-positive methadone levels have been documented with diphenhydramine 100 to 200 mg 2-4,14 and doxylamine intoxication. 4,15 Additionally, doxylamine intoxication has produced false-positive opiate 14 and PCP 2 levels, and brompheniramine use may cause false-positive amphetamine 4 and LSD 3,9 levels. Consider using second-generation. False-positive oral fluid rapid HIV tests. New York City, MMWR Morbidity and mortality weekly report. 2005-2008. 57:660-5. NYC reports spate of HIV false positives with oral test

After the positive HBsAg results were reported, an epidemiologic investigation was initiated by NDHHS and the Lincoln-Lancaster County Health Department to determine the cause of the false-negative test results and to identify any HBV transmission False positive results are quite a rare event, but in a community where very few people have HIV, true positive results are even rarer. In a setting where HIV is more common, a reactive result is less likely to be a false positive. For example, take a test with 99.5% sensitivity and 99.5% specificity

02.05.2021 All articles in can keflex cause a false positive drug test: Para que sirve keflex suspension. Women with bad immune mediators are most formidable to this type of supplemental Heterophile antibodies present in the serum of some patients may cause a false positive result in this assay. Comments: This assay may be significantly impacted by high-dose biotin (>5 mg dose) taken within previous 12 hours In some cases, too much biotin will cause false highs on tests, while in others, the vitamin may cause test results to read low. Excess biotin has also been shown to distort tests for: Thyroid Pregnancy Heart failure Iron-deficiency anemia Certain forms of cancer8 These lab distortions mean that high doses of biotin can cause false positives. More recent scientific tests show that taking too much Biotin can also throw off blood test results. It can as much create a false positive for women taking pregnancy tests as false negatives for people going in for cancer screenings. Hair loss is a very common disorder and there are treatments to help reduce the rate at which you shed your hair For instance, if you take a pregnancy test too soon, you could have a false negative result because the hCG hormone hasn't reached detectable levels quite yet. False-positive pregnancy test results, on the other hand, occur for a number of reasons. Possible Causes of a False Positive Pregnancy Test Ectopic Pregnancy

What Causes a False Positive Pregnancy Test? - Center of

Too much biotin supplement when trying to get pregnant may hinders you from conceiving or taking too much vitamin H while pregnant can cause a miscarriage. Though it is necessary to take biotin supplements during pregnancy but not excessive. Side effects of biotin do varies from one person to another Also important: An iron supplement can produce a false-positive reading on a fecal occult blood test. Excess iron in red blood cells can be mistaken for blood in the stool. Iron supplements also can skew the results of iron tests. If you are scheduled for a fecal occult (or iron) blood test, be sure to tell your doctor if you're taking iron.< A syphilis test false positive is the situation where a person who does not have syphilis is diagnosed with syphilis based on the results of the test. There is something known as a biological false positive condition for syphilis. Some people may test positive for syphilis if they have some underlying medical condition such as lupus Some weight loss products also can cause false positives, as can some nasal sprays and asthma medications. Amoxicillin can cause problems on a drug test. Certain foods can sometimes result in a false positive on a drug test. Many people are familiar with the fact that poppy seeds can throw off the results by showing up as an opiate

Low positive values (0.35-1.0 IU/mL) may not repeat as positive in some patient populations; some authorities recommend that the patient be retested to confirm low positive tests. My calculated value of 1.06 (TB antigen tube value minus the Nil tube value) can show a 52% reversion rate. Copy link to clipboard. Bookmark TSH can be a helpful test but it really falls short under many circumstances in both the diagnosis and management of hypothyroidism. For several reasons (including pituitary sensitivity to thyroid hormone, hormone changes and differences in thyroid medication) measuring the TSH isn't the most accurate thyroid lab test High amounts of biotin can actually create false positives in laboratory tests for thyroid disease and heart attacks — yikes! Some claim that taking biotin can cause you to gain weight. Cephalosporins can cause false-positive laboratory test results in urine glucose and urine ketone tests, just as in the direct Coombs test (used to recognize immune-mediated hemolytic anemia). Penicillin-type anti-infection medications like amoxicillin and ampicillin can likewise cause wrongly high glucose test results

Ca-15-3 can be used to monitor the response to breast cancer recurrence treatment. However, the results alone cannot be the sole guide to predict the occurrence of metastatic spread. False positive results in raised Ca-15-3 can also be caused by non-cancerous conditions, the list is quite long What Can a UTI Cause If Not Treated Properly? If not treated properly, a UTI can turn into a kidney infection, which can produce more serious symptoms. In addition, although extremely rare, a urinary tract infection or kidney disease can also signal a false positive on a pregnancy test. UTI Treatment. Drink plenty of water How Biotin Affects Test Results. Although supplementing with biotin can be beneficial for the body, this substance can greatly interfere with test results. The FDA (Food and Drug Administration) mentioned that biotin could alter blood test results and cause incorrect diagnosis for certain health conditions

Biotin Found in Multivitamins May Interfere with Important

  1. ation. false-negative. does not indicate a false result. false-positive. does not result a positive result gestational diabetes. elevated blood sugar during pregnancy.
  2. Several drugs cause positive and negative interference through these mechanisms resulting in false positive and negative estimates of serum creatinine which may affect glomerular filtration rate (GFR) calculation also. Endogenous substances also affect the creatinine assay systems resulting in false estimate of serum creatinine concentration
  3. Supporting pregnancy and breastfeeding. Its worst side effect can create false positives in lab tests for your thyroid disease. info, research there's no credible evidence that may confirm that biotin can cause high blood sugar. There are certain case studies which show that biotin has been helpful in reducing the blood sugar level.

Biotin can make the test look hyperthyroid with a low TSH, high T3, and high T4, and it can even create false-positive tests for thyroid antibodies. Before you suspect Graves disease, take a biotin supplement history. Troponin. Biotin can cause a false-negative troponin where troponin levels can be normal when a heart attack is actually occurring Because women's menstrual cycles can vary, those women may not have enough hCG for the test to pick up yet. If you receive a negative pregnancy test, you should wait a few days and try it again.

At the same time, deficiency in biotin can contribute to weight loss. Scientific evidence supports the positive effect of biotin for hair growth, but you should consult your doctor prior to using a supplement. In some cases, biotin can disturb thyroid laboratory test results, but sticking to recommended intake could help avoid unwanted scenarios A positive test for ANA does not mean you have an autoimmune disease. The test finds small amounts of these antibodies in up to 15% of healthy people. Antinuclear antibodies are measured in titers. A titer above 1:160 is a positive test result. A positive result may mean: You have systemic lupus erythematosis, or SLE Here, 3 weird things that can cause false positive cancer screenings. 1. Tattoos. In 2012 doctors in California told a cervical cancer patient her cancer had spread to lymph nodes along her thighs.

Can Thyroid Medicine Cause A False Negative Pregnancy Test

Eating raw egg whites — egg whites can bind to biotin in your intestine, keeping it from being absorbed. If you ate two or more uncooked egg whites daily for several months, you could develop a biotin deficiency.; Being pregnant, which increases your need for biotin.Biotin is important for normal embryonic growth, making it a critical nutrient during pregnancy In the vast majority of cases, the result of the hepatitis C virus (HCV) test is definitive, accurately stating whether an individual has contracted the virus that can cause serious liver damage over time. However, in more rare cases false positive results occur—when someone tests positive but is not actually infected

INTRODUCTION. Human chorionic gonadotropin (hCG) is an important biomarker for detection of pregnancy and pregnancy-related disorders, as well as a useful tumor marker, particularly in the management of trophoblastic disease and germ cell neoplasias. It is also a component of some prenatal screening tests for Down syndrome A missed menstruation cycle is one of the earliest signs of pregnancy.That's why we usually recommend waiting until you've missed your period before taking a pregnancy test.You can purchase low cost, high quality pregnancy tests here.If you can't wait that long and you know the day of your last period we can calculate possible conception and your due date Does Biotin Cause Acne As a result, a deficiency of pantothenic acid or excess of biotin—could result in acne flares In more simple terms, you might be making it possible for a deficiency of B5 by using a surplus of biotin—and that's what's making..

Before you get too worried, it's worth pointing out that it's not the actual biotin that's potentially harmful — it's the fact that it can skew blood tests (like providing false positive on pregnancy tests, or false negatives on cancer or cardiac health tests)

FDA Safety Alert: Biotin Can Affect Medical Test Results

Question as asked: How effective is Biotin? Vitamins are a thing that if your body doesn't have enough of them, you can have health problems. But having more than necessary is at best useless, and at worst can cause problems of its own. (Fortunate.. If you take a biotin supplement, it can produce false-positive or false-negative lab test results, which may lead to misdiagnoses or unnecessary treatments for heart disease, thyroid conditions, breast cancer, pregnancy and fertility. The good news is that not all lab tests are affected by biotin ; s, including biotin, thi

Another cause of false-negative pregnancy test results is erratic or improper testing techniques. Most test sticks need to be saturated in urine to get accurate results. If you do not leave your test strip in the urine long enough, it could give you false negative or false positive pregnancy test results The best initial test is for HBV is the IgM antibody for acute infection, and IgG antibody for chronic HBV. Acute hepatitis B can display the following symptoms: fever, fatigue, nausea, loss of appetite, and vomiting, as well as joint pain, jaundice, stomach/abdominal pain, dark urine and/or gray-colored stool Thyroid blood tests are generally straightforward and accurate, but certain factors can affect your individual results. Persistent fluctuations can occur, and they are a sign that you need your medication dose changed. But your test results can also be falsely skewed due to factors such as the time of day, or temporary conditions, such as illness or pregnancy—meaning your recorded levels may.

Video: Taking Biotin Can Screw Up Cancer Screening Results Glamou

Studies show that deficiency in biotin can cause decreased glucose utilization and impaired glucose tolerance. Incorporating biotin in your diet can help your body maintain normal levels of glucose and use it properly. Role of Biotin in Pregnancy. Like many other nutrients, biotin is also essential for pregnant or breastfeeding mothers Certain tests can be performed with your blood or urine to know if you are using drugs. One of those is the THC urine test which will search for tetrahydrocannabinol (THC) - a metabolite of marijuana. A positive result will indicate a recent use of this drug. But sometimes, this test can give a false positive when you have never used marijuana One serious drawback of hair EtG testing is that false negatives can occur if the hair is permed, bleached, or dyed. Also, ethanol-containing hairspray or hair lotions may cause false positives 12. A urine test for ethyl sulfate (EtS) has a similar response pattern to the EtG This is one of the test results that dictates how we proceed with considering a heart attack. If negative on three different occasions, your symptoms are likely not to be due to your heart and we consider other options. High doses of biotin will cause this test to be falsely negative in some cases of heart attack, that means a missed heart attack Several over-the-counter medications such as common cold, allergy and sinus medications have been known to cause false positive drug tests. Ibuprofen in any form sometimes causes a false positive for marijuana use. Cold remedy medications with codeine have caused a false positive for use of morphine. Other medications to be aware of include. A false positive EtG hair test in a woman after regular use of EtG-containing hair lotion (rare) not being washed out after use, was described in one study [6]. Ethanol from hair cosmetics or other sources absorbed into the hair from the outside (not from the body) are not converted to EtG in the hair, and does not cause a false positive EtG.