Obviously the question of using a CPAP machine without prescription medication is one that you should talk over with your doctor.  Only he or she can actually diagnose your cause of sleeplessness or determine why you need a CPAP machine and can also determine if your condition is improving, staying the same, or even getting worse.  Unfortunately there are some cases or conditions that warrant such a device that actually get worse as time goes on, so using just the CPAP machine without prescription medication is not going to be very effective.  For example, if one has severe asthma the lungs and airways have a tendency to stiffen up so that air cannot circulate the way it should.  While a CPAP machine may force oxygen into this airway, using the CPAP machine without prescription medication to relax the lungs and airways is not going to do much good.  Just having oxygen in the lungs is not going to be effective if those lungs cannot constrict and expand the way they should.

Some have taken it upon themselves to use a CPAP machine without prescription medication, figuring that the machine will do the job that the medications are supposed to do.  In some cases this might be acceptable but usually a doctor prescribed a medication for a reason.  If he or she determines that you need medicine to improve or assist your lung function there is probably a good reason for this.  Assuming that you can just use your CPAP machine without prescription medication can be dangerous and in some cases downright deadly.  It's unfortunate that some people have actually died in their sleep from untreated cases of sleep apnea and other such diseases, so you need to follow your doctor's instructions carefully.  Never use your CPAP machine without prescription medication unless he or she gives you the green light to do so.