Studies have shown that 40% of workers fake their sickness to obtain a free day from their job, when they are perfectly fine. Many companies check up their employees for being sure that they are really sick or just pretending to be. Other organizations hire someone to find out the truth about their workers.
Take care if you are going to do this because you will probably end up without your actual job. In the U.S, workers have the possibility to take 10 paid vacation days per year, and in some cases that figure includes sick time.
Normally, an employer will separate vacation from sick time, offering some paid days for each. Hence, if you spend all your free days, probably your next step for having another day is to pretend to be sick.
Don’t forget that your employer can verify you and ask you some questions about your doctor, or offer treatment to prove your illness. Before doing this, try to talk to your manager about your problem. You can be honest with him and probably he could help you to take a day off without lying.
Of course, if you are really sick stay at home, all you have to do is to be honest and things will be ok. If you take advantage of your job and lie with your health status when you are sick, no one will trust you in the future.