Miralax

My 16 yr old cat has had constipation problems & is having this issue again . I gave her 1/4 tsp of miralax & she has vomited some foamy liquid . Is this a usual occurrence after administering miralax ?

Did you mix it into wet food with a bit of water added?  That used to work like a charm for me.

It is not normal for a cat to vomit Miralax; it is more likely your cat is vomiting due to being constipated.  http://www.felineconstipation.org/whatgoeswrong.html

Has your cat pooped recently?  If not, I would call your vet and have your kitty checked.  Miralax is not going to work if there is any chance of impacted stool. Please let us know he she is doing.