If you suffer from any circulatory or blood disease, you should not use vibration machines. Other conditions that prohibit using such machines include the likes of diabetes, blood coagulation disorders and some other skin related conditions. If you do not suffer from any of these but still experience rashes, discomfort or an acute pain whenever vibrations are applied you should cease to use the machines immediately and consult a doctor. Vibration machines are not a toy and they should not be treated as such. Also, the age of the one who uses the machine is very important.
Not everyone should use it. Sometimes some people may find that it is not counter indicated, but that they need to keep the vibration cycles lower. Always consult the manual; if possible ask a nutritionist or a medic if you suffer from any ailments that may impede the use of vibration plate machines. If you experience any uncomfortable symptoms, always cease using the machine and get some specialist advice.