stomach sickness

Question
Hi,
I have a poodle/shnauzer mix. Recently, her stomach has seemed to be upset. I have no idea why though. She has had dirrarea and has been throwing up. However, it doesn't seem serious, as she doesn't constantly do these things. She's also acting pretty normal. Please tell me what you think I should do. Thank you.
                          Sue

Answer
There could easily be a number of reasons for this.  If she is not spayed, she could be coming into heat.  Has she been around a male if not spayed?  This is also a symptom of pregnancy.  Have you changed her diet recently?  This can also be a cause.  She could also possibly be sick.  Is she up to date on her shots?  If none of these seem to be a cause, I would get her to a vet asap.