Question
How effective are mannitol and dexamethasone in reducing brain edema? How long does it generally take for the swelling to subside after taking these medications?
Answer
Mannitol combined with dexamethasone is the preferred medication in neurology for improving symptoms of brain edema. Mannitol does not remove the water from the tumor-induced swelling, but rather removes water from the brain tissue to alleviate the symptoms of brain compression. Therefore, this medication is only for symptom relief and not a treatment for edema itself. To treat edema, one must address the tumor, either through surgical removal or radiation therapy to shrink or necrotize the tumor to reduce swelling.