Topamax and kidneys...these two will probably never be BFF's

I've noticed in looking at my blog statistics that a previous entry on kidney stones resulting from topiramate (Topamax) use continues to be one of my most visited pages on this blog. So when I found more information about this medication and its effect on kidneys I wanted to be sure to share it.

Within 5 days of starting topiramate, the six subjects in this study experienced an average drop of calcium in their urine of about 31% and of citrate by about 40%. When calcium and citrate are not showing up in the urine, it's likely because it's accumulating elsewhere. Like in kidney stones.

Interestingly, increasing the topiramate dose seemed to improve calcium readings and to worsen citrate readings. Meaning you might get less of one kind of kidney stone and more of another.

The authors of this study said that the degree of reduction of urinary citrate was profound enough to be compared to the clinical presentation of renal tubular acidosis. This is a condition in which the body's pH is shifted to an unhealthy level, promoting important changes such as bone demineralization. And THIS will cause rickets in children and osteomalacia in adults. These are not things you will see or feel in those first few days. You need to measure them clinically.

I would strongly recommend, if you and your physician have concluded that the absolute only way to manage your bipolar disorder, your migraine, or your epilepsy, is with topiramate, that you closely monitor your urinary metabolites to be sure you're not doing more harm than good.

And if you're one of those souls who's been convinced that it might be nice to try topiramate to see if it helps you lose weight, consider that you might not just be
losing fat, you might also be losing bone. What's the point of being thin if you have to be sick when you get there?

The only way to know is to monitor. Please don't stick your head in the sand and hope it's not happening to you.

Warner BW, LaGrange CA, Tucker T, Bensalem-Owen M, Pais VM Jr. Induction of progressive profound hypocitraturia with increasing doses of topiramate. Urology. 2008 Jul;72(1):29-32; discussion 32-3.



I found a photo of a kidney stone on the 'net. Imagine trying how it feels to pass something this big through an opening about as big as a piece of cooked pasta. Now you know why I'm trying to get your attention!