I used to have problems feeling cold and having cold extremities because my body temperature was two degrees below normal and I had low blood pressure. The Two things which have fixed this problem for me are high doses of T3 and taking Pregnenolone. I found out that I needed high doeses of T3 because testing showed that my reverse T3 was very high. Many of us with CFS have high reverse T3 because we have one or more chronic infections and one way our bodies are responding is by trying to slow down our metabolisms by turning off the thyroid. One of the effects of this is that it lowers body temperature. Another is that it further hampers our immune systems from functioning properly. I needed a lot of T3 to counteract this effect. Right now I'm on 510 mg a day and my pulse and temperature are finally normal for the first time in years.
I'm also taking 100 mg of Pregnenolone and this has definitely helped improve my ability to tolerate cold. . I'm not sure about other countries, but in the US Pregnenolone is available as a supplement. However, it's important to get a decent brand. I'm using NSI Pregnenolone 50 mg. It's $13 for 180 capsules and it seems to work well for me. I knew that I needed pregnenolone because my blood level was 0. Apparently, this is very common for people with CFS. Interestingly, when I first started taking 100 mg of pregnenolone, my body had problems tolerating the dose. But then I read an article which talked about how the chronic viral infections present in CFS often result in Co-q10 defficiency, and how Co-q10 is necessary for the body to make and utilize Pregnenolone. So I started supplementing with 200 mg of Co-q10. This seems to have worked for me because 100 mg now feels like the right dose for me. Mentally, I feel much more positive, and I do much better in cold weather and so don't have to dread winter like I used to.