If a spider crawls on the body without a bite, it usually does not do anything, and if a bite occurs, itching, pain, weakness and other discomforts are likely to occur.
To determine what will happen if a spider crawls on your body depends on the actual situation and cannot be generalized, it mainly depends on whether you have been bitten by a spider or not. If the spider is simply crawling on the body, and did not happen to bite, generally will not be how, so do not worry too much, and timely take the paper will be brushed off.
However, if the spider has already bitten the skin while crawling on the body, itching, pain, redness, swelling, etc. will occur locally, and some patients will also suffer from weakness, dizziness, fever, etc. after being bitten by the spider, which may be life-threatening to a certain extent if not treated in time.
In summary, when found that the spider crawling on the body after the discomfort, need to go to the hospital in time, with the doctor active treatment.