Dear Camilla, I thought your message regarding Peter's experience at the dentist was something which should be shared by a wider audience, so I am asking your permission to run this in our Newsletter sometime. I may in fact get one of the neurologists to answer the question. It is certainly something which people should be aware of. Isn't is strange that some extreme forms of stress, such as real danger, will instigate a "flight and fight" response to enable a previously frozen PWP to move, but other forms of stress, just stop the medication from working. I am wondering if the anaesthetic he was given had a delayed reaction... Can you find out the name of the anaesthetic -- Also, is there a possibility that the ampicillin affected the rate of absorption of his medication somehow? if it was absorbed more quickly, then he would run out of cover, so to speak. Anyway, how lucky he was to have such an astute caregiver Best wishes Joy Graham (CG Bob, 57, 8 yrs)