Losing appetite/weight while breastfeeding

Estephine

I have a 4 month old baby, he’s 18lbs 26in. But he is literally sucking the fat out of me! 😩 I have no appetite and breastfeeding is making me lose more weight that I need too. At my 6 week pp visit I weighed 140lbs now I weight 115lbs... I’m drinking boost plus but I feel like that’s not working, what can I do? Has anyone been through this? Help 😟