 [ Symptoms ] i had an allergic reaction likely something i ate can i just re try these foods to determine which caused the allergy  i am not sure it is something i ate tongue throat inside of mouth did not swell or itch my face turned red and hot and became swollen and i had hives on my neck and chest the possible culprit food list is very short so can i just eat a little of one thing wait a few days and if there is no allergic response try another thing on the list [ Disease ] no thc can be detected by modern drug testing blood urine and hair for quite some time the only way to be sure that thc does not show up on a drug screening test is to not use cannabis