is it okay to lower fevers in adults or children by giving them lukewarm baths?

Lukewarm baths (not cold water, please!) are a great way to lower the temperature, especially in babies who have a much greater skin surface relative to their size than do adults. To bring a fever above 101 down, it's generally recommended to start with acetaminophen (Tylenol), and you can also add ibuprofen after 2 hours if the temp is still above 101. Adjust the dosages of each as indicated on the label 

Of course, if you don't know what the cause of the fever is, you may also need to see your doctor - especially if your child has a headache or any neck pain, is short of breath, hurts on urination, has drainage from ears, or just looks ill.