Occasional foamy urine is usually normal and may be caused by urinating too quickly.

However, if foaming in the urine becomes persistent—especially if it continues noticeably in the mornings or is accompanied by additional symptoms such as swelling in the legs—it may be a sign of protein in the urine. Since this could be one of the early signs of kidney disease, it should be evaluated.

I recommend that patients who consistently complain of foamy urine have a simple urinalysis done.