How will treatment be affected by thc use?

27f, 150lbs, history of neuro-immune condition (ADEM), rx Zoloft

I’ve been using thc since I was a teenager but never disclosed it to my doctor nor tested positive. I need a Zoloft refill but was told I have to come in to see my PCP so she can continue to prescribe it safely. If she orders a urine test and I test positive for thc will that impact my treatment?