Is this you who's temp is dropping and falling?
Are you taking meds?
What is causing you to take your temperature?
How big are the increases and decreases?
Are you meaning cold and hot flashes?
Or are you actually taking your temp and noticing the changes?
Are you male or female?
There are several factors that come into play with hot flashes. The number one factor being hormones. Lower levels of estrogen can confuse the hypothalamus, making it think you are too hot.
http://www.breastcancer.org/tips/menopausal/facing/hot_flashes.jsp Here is a link that will give you tons and tons of info on hot flashes. I think you will find it useful.
Sometimes the sweating that is caused by a hot flash can result in a chill afterwards.
These can also be caused by anxiety. http://www.livingwithanxiety.com/anxiety-symptoms-hot-cold-flashes.htm It is common for people with anxiety to have hot and cold flashes as well. Adrenelin plays a major factor in this.
You should consult with your physician as to the cause of your hot and cold flashes. It may be that there are medicines or alternative type therapies that you could benefit from.
Let me know if you would like more info.
I hope this helps,