lossing weight

I have been losing weight way to fast and can't stop it. I have hyperthyroid. My sister is doing the same thing. We eat everything that might put weight on us and nothing happens. I'm 5'8" and 120 lbs. she is 5'6: and 94lbs. Can anyone tell us what we can do? The doctor can't.

First - start looking for another Dr.! No way should one let your sister get that underweight. You must be experiencing dizziness & heart problems by now? You don't say what type of Dr. your using? An Endocrinologist needs to be seen soon. And eating alone doesn't always put weight on when your hyper, you have to actually cut back on any exercise your doing too if you are doing it on a regular basis. Not to mention any other drugs you both may be on could be involved in this. But if you Thyroid levels were being managed this wouldn't be happening unless there are other health issues involved you don't mention or haven't been checked for. Look up a Dr. here soon.under the Tools Tab or check with your Health Care provider.