My husband is on metformin and syntyroid. He burned after using a tanning bed after only 5 uses. In these 5 times he increased the time from 6MIN up to 9Min, he has done this in the past and has not had this problem. In fact it has been a week and his skin is still very itchy, never peeled and has red spots, small pin prick size spots. Is sunlamps contraindicated with metformin and or Synthroid use?