I don't know about cabbage leaves, but my friend had that and was advised to take care of it before it developed into full-blown mastitis. She was told to nurse as much as possible and not skip feedings to make sure the milk drained, to rest as much as possible, and to make sure she had a well-fitting bra (no wires.)
I hope it clears up for you!
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Cabbage leaves are for reliving engorgement when trying to wean. They're not for clogged ducts.
Amneris' advice is right on. I would add that you should nurse with baby's chin pointing to the clogged duct to drain it better, even if you have to contort yourselves to do it. Also, nursing while on hands and knees with breast hanging over baby lying on the floor or bed beneath you will help drain it better also. It will hurt, but you've got to keep it drained.
I used to have a milk duct clog once and a while. I think it was the way Bella would nurse on a certain side. I used warm, damp compresses to relieve it, and nursed as often as I could on that side. I found that nursing laying down in a sidelying position helped. It must've been the angle she was nursing in order to drain it.
Really warm rags on it and then do a pressure massage on it. There is a special way to do it. Let me dig up the info.
Try a pressure massage on the area of your breast that is swollen and painful because of a plugged duct. This may help to loosen the plug. With pressure massage, you do not actually move your hand over the skin as you would with a normal massage. You simply press more and more firmly with the heel of your hand to move the plug in the duct down closer to the nipple.
To do pressure massage, start at the edge of the lumpy area closest to your chest wall. Apply pressure to that area with the heel of your hand to the point just before it becomes too painful. Hold the pressure at that level until the pain eases off. Then increase the pressure again, (without moving your hand) and hold it until the pain eases. Continue to gradually increase pressure at that same site until you are pressing as hard as you can. Then pick your hand up, move it down toward your nipple about a half inch, and repeat the pressure massage in this area. Continue moving your hand a half inch and repeating the massage until you get all the way down to the nipple.
The above came from Dr. Sears' site. I had plugged ducts frequently and it really helped. My lactation consultant also suggested running a comb (yes, a hair comb) over the breast. I can't remember if I tried that one or not.
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