Sunday, October 7, 2018

Home Urine test and what the Faint Line means

Negative or Positive Test Result ?


 Is your self test Qualitative or  Semi quantitative  ?

A very common question with people who are worried about seeing a faint line on the home reagent dip strip test is what does this mean ? well it depends on what kind of strip it is .
These are strips which serve different purposes, such as a qualitative strip that only determines if the sample is positive or negative, such as most cheap single store bought dip strip test ( can be cup type as well).  
These are a basic preliminary qualitative (quality )  test and thus are not SEMI quantitative  (quantity ) test so they will not show a estimate of a quantitative result in which a color reaction is proportional to the concentration of the substance in sample carried out by comparing the test pad to a chart or react to a lighter / darker line like a CARD or CUP that is SEMI quantitative . 




 If a strip also used in cups has multi colored indicators its a SEMI quantitative  (quantity ) typical of a Validation panel in addition to the drug screen . These will show If the creatinine and specific gravity (urine density) are in range ( this shows if sample is diluted) , as well as other factors to determine if sample is in human range and even shows no additive are present.









You will hear from people on forums even read bad info on sites stating Dilution or  being  borderline  to be a cause of faint lines on these dip stick THC test but remember many of these dip sticks are  qualitative so it will react or will not and usually are faint anyway.

Whats worrying and nerve racking to some is getting a faint line which leads them  to wounder am i just a little dirty ?

NO your not  THC has a LOW cut off or threshold and so the line will always be fainter than say coke. If you see it at all its negative. 
In case of certian drugs, the minimum drug quantity ( threshold or cut off value) is rather high such as amphetamines (1000ng/ml) whereas it’s low in other drugs such as marijuana (50ng/ml). The lower the minimum amount (threshold), the lighter the line will be in negative urine for a qualitative test.



 HOWEVER many doing self test are also in middle of detoxing and may be over hydrated at the time and then do another self test days later and be positive. This is a true level and this also shows why detox drinks do not actually detox you they only dilute you for a short window.  Always test in morning or when not overly hydrate to get true answer .

Sometimes a lab will use a reagent stick validation before "accepting" the sample to sent to the lab for drug screening . a validation test verifies its ph, color, specific gravity ( verifies dilution ) creatnine level ( not creatine) and looks for nitrates or non urine AGENTS


When reading the drug test result, you will find a line at the very top of every testing window and that is the control region (C). The test is not considered valid without this line. Result is considered negative when a colored line appears in both the control (C) and test (T) region. If the colored line appears in the control region but not in the test region, the test is considered to be positive. Nevertheless, presence of any faint line in the test region (T) will indicate negative results no matter how light it is.

Positive test cup Negative test cup
Presumptive Positive: One colored line is visible in the control (C) zone for that drug. No colored line whatsoever appears in the test (T) zone, indicating a presumptive positive result for the corresponding drug.
Negative: Colored lines are visible in both the control (C) and test (T) zones, indicating that concentration of the drug is below the detection limit of the test or not present.

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