Can I claim a child that is not mine as a dependant, there medicaid is not under my name but I did support them finacially and gave them rides to school doctor ext. ?

Did that child live with you all of 2017? What about his/her parents?

Also be aware that any support you provide could impact their Medicaid.

It depends.

You can claim a child, relative, friend, fiancé (etc.) as a dependent on your 2017 taxes as long as you meet IRS requirements. Giving rides to school is not an IRS qualification for dependent. Use the link below to determine if you can claim the child:

https://ttlc.intuit.com/replies/5187060

 In addition, TurboTax will guide you through the dependent qualification steps.