I have always seen that 72 hours was the max for blood test, no matter how much you smoke. Urine is longer because the kidneys take the metabolites out from the large blood volume you have and basically reconcentrates it in the urine. There is nothing that can be done for blood test but time.
FakeBoobsRule Reviewed by FakeBoobsRule on . Blood test Sometime during summer I will be going to a new doctor, so he needs to do a routine lab where I'll be given a blood test and maybe a urine test. I was wondering how long I had to go without smoking to be able to pass a blood test, and if there was something I could do to help pass the test. Thanks in advance. Rating: 5