Behavior change

Question
Our Leopard Gecko "Elizabeth" has been a very low maintenance, enthusiastic eater for the last 10 years.  She has been fed only crickets and calcium and supplied with bottled water.  We use the bark that is sold from the pet stores. Three weeks ago she was fed a black wild cricket which probably had a hard shell.  She did not eat for 3 weeks so we fear impaction.  We brought her to a vet who advised us to keep up her heat in one corner of her tank and to give her warm water soaks which we do twice a day.  My husband is also able to get her to eat a cricket or two if he holds it up to her mouth for a total of 5 since this began.  She has not had a bowel movement since, yet either.  We have noticed that her skin is turning darker as well.  Any suggestions would be great, as this is awful to watch her slowly go down hill.  Thank you

Answer
Hi Julie,
I am sorry to hear you are having problems with your "Elizabeth"
With Leos, they need to have a warm area in their tank that is 88-92 degrees.  Did you take the temperature higher than that range as suggested by the vet? I wouldn't go any higher than 94 degrees.
A cricket from the wild can cause many problems due to pesticides and fertilizers and other toxins. Even though you may not use any of those items in your yard, its not possible to know where the cricket came from.  
Did the Vet take x rays to see if there was indeed an impaction? Its vital to know to what extent there is an impaction as that if it is an intestinal blockage, adding more food, or "forcing" her to go to the bathroom can cause grave damage. If there was an xray taken and there isn't intestinal blockage,
you can try offering her some watermelon or baby food fruits(such as prunes)..or even baby food meats.  My leo loves to nibble at watermelon and it will help increase her water intake. She will most likely lick at the foods from your finger, or placing a tiny, tiny drop on her "lips".
Try offering a few wax worms to get her more interested in eating.  Only a few though!!  They are way too fattening and the Leos can get very spoiled and want them all the time.  We refer to the wax worms as "Lizard Candy"
The bark isn't a great substrate for geckos as that it holds too much moisture for a Leo.  Shes had it for 10 yrs with no problems and even though it would be best to switch to newspaper or other substrate such as that, I don't recommend changing it now.  The reason is.... geckos hate change!!  They will many times stop eating for  quite awhile until they adjust to what ever is new to them.  Has anything changed in her tank?  Even little things like moving a dish can upset them.
I would again contact the vet.  If your vet is not well educated in reptiles, you can find one that is by going to www.anapsid.org/vets  
Geckos can also get cancer, tumors, abscesses, etc in there organs,which having an xray will show if this can possibly be the problem.  Please keep us posted as to how Elizabeth is doing.  My thoughts are with you.