Does it take 4 weeks for nicotine to get out of your blood system and not show up in a test?

Possibly: Nicotine is highly fat-soluble, so it may be stored in fat cells. Half-life of nicotine is ≈ 2 hrs, but its metabolite cotinine's half-life is 20 hrs. Ideally after 8 days only 1/1000th of the original amount should remain. Asians metabolize nicotine more slowly, & urine acidity (ph) affects excretion. If nicotine/ cotinine still shows after 4 weeks, it must be being released from fat.

What is your usage??: “When someone stops using tobacco and nicotine products, it can take more than two weeks for the blood level of cotinine to drop to the level that a non-tobacco user would have and several weeks more for the urine level to decrease to a very low concentration.” REF: http://labtestsonline.org/understanding/analytes/nicotine/tab/test/

Dr Hickerson agreed