Breastfeeding and Formula

Mandy • 29 years old - Married October 2013 - Mom of Baby Girl Dec 2015 😊 Expecting Baby Boy April 2018 ☺️
So my baby is having pretty bad lower gi digestive issues and it has been agreed by my lax consultant and pediatrician that it may be time to try a specialized formula with my baby. She is currently 5 weeks and we wouldn't be making the transition off of breastmilk until after her 6 week mark but I'm feeling incredibly guilty about the decision. Is it possible to continue to give her at least one bottle of breastmilk or maybe even mix it in with a couple formula bottles a day? Does anyone currently do this? I see it as a supplemental vitamin at this point and I feel like any breastmilk is better than none.