Although flushing, sudden sweats and perceptions of changes in body temperature or temperature regulation can be caused by the action of CRPS itself, there are many other things that can cause symptoms like that. Virtually all of the drugs commonly used to treat the various symptoms of CRPS also cause hot flushes and sweating. Weight loss associated with stress or drug related nausea will tend to cause a person to feel cold much of the time. Not eating regularly can make some people feel cold and then they flush and sweat as soon as their body starts to process food.

All of the varieties of anti-depressants - tricyclic, SSRI, SNRI etc commonly cause sudden flushing episodes and excessive sweating. All opioids have this as a very common side effect, methadone is thought to be particularly bad for this.

Women with CRPS also need to bear in mind that hormonal changes associated with the various stages of menopause can cause body temperature regulation problems and exactly the same flushing/sweating issues. Even the hormonal changes associated with a normal menstrual cycle can cause core body temperature elevation along with sweating and flushing, especially at night, at various points of the cycle. I only mention all this because like all of the other changes people notice with a complex condition like CRPS, its just as likely that they are being caused by something other than CRPS.

I only make these points because its always so important not to just assume that every symptom or change is caused by CRPS. Personally, I think its usually safer to start from a position of assuming that anything new or different is not caused by CRPS so that you can be properly objective in assessing what is most likely to be causing any new problem. It may be that there are effective treatment options for some of these unpleasant symptoms when they aren't being caused by CRPS. By just assuming they are all CRPS related, it would be very easy to completely miss out on important testing and/or an effective treatment for the real cause of problems.